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HomeMy WebLinkAbout34 E Santa Clara St - 2024 - Stormwater pollution prevention planSTORMWATER POLLUTION PREVENTION PLAN for Alexan Arcadia RISK LEVEL 1 WASTE DISCHARGE IDENTIFICATION NUMBER (WDID): ______ _______ Legally Responsible Person [LRP]: Arcadia Apartments LLC 5790 Fleet Street, Suite 140, Carlsbad CA 92008 Todd Phillips (760) 431 3366 Approved Signatory: same as above Prepared for: Arcadia Apartments LLC 5790 Fleet Street, Suite 140, Carlsbad CA 92008 Project Address: 34 E Santa Clara Street, Arcadia, CA 92008 SWPPP Prepared by: Psomas 27220 Turnberry Lane, Suite 190, Valencia CA 91355 Leah Isidro, PE SWPPP Preparation Date December 11, 2023 Estimated Project Dates: Start of Construction December 1, 2023 Completion of Construction July 01, 2026 Alexan Arcadia i August 2023 Table of Contents Qualified SWPPP Developer ................................................................................... 1 Legally Responsible Person ................................................................................... 2 Amendment Log .................................................................................................... 3 Section 1 SWPPP Requirements .................................................................... 4 1.1 Introduction ........................................................................................................................ 4 1.2 Permit Registration Documents ..................................................................................... 4 1.3 SWPPP Availability and Implementation ....................................................................... 5 1.4 SWPPP Amendments...................................................................................................... 5 1.5 Retention of Records ...................................................................................................... 6 1.6 Required Non-Compliance Reporting .............................................................................7 1.7 Annual Report ..................................................................................................................7 1.8 Changes to Permit Coverage ............................................................................................7 1.9 Notice of Termination ......................................................................................................7 Section 2 Project Information ........................................................................ 8 2.1 Project and Site Description ........................................................................................... 8 2.1.1 Site Description ........................................................................................................... 8 2.1.2 Existing Conditions ..................................................................................................... 8 2.1.3 Existing Drainage........................................................................................................ 8 2.1.4 Geology and Groundwater .......................................................................................... 8 2.1.5 Project Description ..................................................................................................... 8 2.1.6 Developed Condition .................................................................................................. 8 2.2 Permits and Governing Documents ................................................................................ 9 2.3 Stormwater Run-On from Offsite Areas ......................................................................... 9 2.4 Findings of the Construction Site Sediment and Receiving Water Risk Determination 9 2.5 Construction Schedule ................................................................................................... 11 2.6 Potential Construction Activity and Pollutant Sources ................................................. 11 2.7 Identification of Non-Stormwater Discharges .............................................................. 11 2.8 Required Site Map Information ..................................................................................... 12 Section 3 Best Management Practices ........................................................... 13 3.1 Schedule for BMP Implementation ............................................................................... 13 3.2 Erosion and Sediment Control ...................................................................................... 14 3.2.1 Erosion Control .......................................................................................................... 14 3.2.2 Sediment Controls ..................................................................................................... 17 Alexan Arcadia ii December 2023 3.3 Non-Stormwater Controls and Waste and Materials Management ............................. 20 3.3.1 Non-Stormwater Controls ........................................................................................ 20 3.3.2 Materials Management and Waste Management ..................................................... 22 3.4 Post construction Stormwater Management Measures ............................................... 24 Section 4 BMP Inspection, Maintenance, and Rain Event Action Plans......... 25 4.1 BMP Inspection and Maintenance ............................................................................... 25 4.2 Rain Event Action Plans ............................................................................................... 25 Section 5 Training ........................................................................................ 26 Section 6 Responsible Parties and Operators................................................ 27 6.1 Responsible Parties ....................................................................................................... 27 6.2 Contractor List .............................................................................................................. 28 Section 7 Construction Site Monitoring Program ........................................ 29 7.1 Purpose ..................................................................................................................... 29 7.2 Applicability of Permit Requirements ...................................................................... 29 7.3. Weather and Rain Event Tracking ............................................................................ 29 7.5 Safety and Monitoring Exemptions .......................................................................... 30 7.6 Visual Monitoring ..................................................................................................... 30 7.7 Water Quality Sampling and Analysis ...................................................................... 34 7.8 Active Treatment System Monitoring....................................................................... 44 7.9 Bioassessment Monitoring ....................................................................................... 44 7.10 Watershed Monitoring Option ................................................................................. 44 7.11 Quality Assurance and Quality Control .................................................................... 44 7.12 Records Retention .................................................................................................... 46 Section 8 References ..................................................................................... 47 Appendix A: Construction General Permit ....................................................... 48 Appendix B: Site Map ....................................................................................... 49 Appendix C: Permit Registration Documents .................................................. 50 Appendix D: SWPPP Amendment Certifications ............................................... 52 Appendix E: Submitted Changes to PRDs ..........................................................54 Appendix F: Construction Schedule ..................................................................56 Appendix G: Construction Activities, Materials Used, and Associated Pollutants 57 Appendix H: CASQA Stormwater BMP Handbook Portal: Construction Fact Sheets 60 Appendix I: BMP Inspection Form ................................................................... 61 Appendix J: Project Specific Rain Event Action Plan Template ....................... 68 Alexan Arcadia iii December 2023 Appendix K: Training Reporting Form ............................................................. 69 Appendix L: Responsible Parties ...................................................................... 71 Appendix M: Contractors and Subcontractors................................................... 73 Appendix N: Calculations .................................................................................. 74 Appendix O: Weather Reports .......................................................................... 75 Appendix P: Monitoring Records ..................................................................... 76 Appendix Q: Example Storm Event Monitoring Forms ..................................... 77 Appendix R: Field Meter Instructions .............................................................. 86 Appendix S: Supplemental Information ........................................................... 87 Alexan Arcadia 1 December 2023 Qualified SWPPP Developer Approval and Certification of the Stormwater Pollution Prevention Plan Project Name: Alexan Arcadia Project Number/ID “This Stormwater Pollution Prevention Plan and its appendices were prepared under my direction to meet the requirements of the California Construction General Permit (SWRCB Orders No. 2009- 009-DWQ as amended by Order 2010-0014-DWQ and Order 2012-0006-DWQ). I certify that I am a Qualified SWPPP Developer in good standing as of the date signed below.” QSD Signature Leah Isidro, PE Date C78541 QSD Name Asst. Project Manager QSD Certificate Number 661-705-4425 Title and Affiliation lisidro@psomas.com Telephone Number Email 12/11/2023 Alexan Arcadia 2 December 2023 Legally Responsible Person Approval and Certification of the Stormwater Pollution Prevention Plan Project Name: Alexan Arcadia Project Number/ID [if applicable] Either the Legally Responsible Person (LRP) or Approved Signatory must electronically sign, certify, and submit via SMARTS to the SWRCB for Notice of Intent, Changes of Information, Annual Reports, and Notices of Termination. In doing so, the LRP or Approved Signatory is certifying: “I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, to the best of my knowledge and belief, the information submitted is, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations.” “I certify that this document and all the attachments were prepared under my direction or supervision in accordance with a system designed to ensure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, to the best of my knowledge and belief, the information submitted is true, accurate, and complete. I am aware that submitting false and/or inaccurate information, failing to update the SWPPP to reflect current conditions, or failing to properly and/or adequately implement the SWPPP may result in revocation of grading and/or other permits or other sanctions provided by law.” The LRP (and Approved Signatory, if applicable) for this project are: Todd Phillips Legally Responsible Person Approved Signatory Alexan Arcadia 3 December 2023 Amendment Log Project Name: Alexan Arcadia Project Number/ID Amendment No. Date Brief Description of Amendment, include section and page number Prepared and Approved By Name: QSD# Name: QSD# Name: QSD# Name: QSD# Name: QSD# Name: QSD# Name: QSD# Name: QSD# Name: QSD# Alexan Arcadia 4 December 2023 Section 1 SWPPP Requirements 1.1 INTRODUCTION The Alexan Arcadia project is located at 34 E Santa Clara Street, Arcadia, California. The site is bound by E. Santa Clara Street to the north, Wheeler Avenue to the south, a public alley to the east and N. Santa Anita Avenue to the west. The property which is owned by Arcadia Apartments LLC, is approximately 2.13 acres. The project’s location is shown on the Site Map in Appendix B. This Stormwater Pollution Prevention Plan (SWPPP) is designed to comply with California’s General Permit for Stormwater Discharges Associated with Construction and Land Disturbance Activities (General Permit) Order No. 2009-0009-DWQ (as amended by 2010- 0014-DWQ and 2012-006-DWQ) (NPDES No. CAS000002) issued by the State Water Resources Control Board (State Water Board) Appendix A. This SWPPP has been prepared following the SWPPP Template provided on the California Stormwater Quality Association Stormwater Best Management Practice Handbook: Construction (CASQA 2019). In accordance with the General Permit, Section XIV, this SWPPP is designed to address the following: · Pollutants and their sources, including sources of sediment associated with construction, construction site erosion, and other activities associated with construction activity are controlled; · Where not otherwise required to be under a Regional Water Quality Control Board (Regional Water Board) permit, all non-stormwater discharges are identified and either eliminated, controlled, or treated; · Site BMPs are effective and result in the reduction or elimination of pollutants in stormwater discharges and authorized non-stormwater discharges from construction activity to the Best Available Technology/Best Control Technology (BAT/BCT) standard; · Calculations and design details, as well as BMP controls, are complete and correct, Appendix A. 1.2 PERMIT REGISTRATION DOCUMENTS Required Permit Registration Documents (PRDs) shall be submitted to the State Water Board via the Stormwater Multi Application and Report Tracking System (SMARTS) by the Legally Responsible Person (LRP) or authorized personnel (i.e., Approved Signatory) under the direction of the LRP. The project-specific PRDs include: 1. Notice of Intent (NOI); 2. Risk Assessment (Construction Site Sediment and Receiving Water Risk Determination); 3. Site Map; 4. Annual Fee; 5. Signed Certification Statement (LRP Certification is provided electronically with SMARTS PRD submittal); and 6. SWPPP. Alexan Arcadia 5 December 2023 Site Maps including Erosion & Sediment Control Plans can be found in Appendix B. A copy of the submitted PRDs shall also be kept in Appendix C along with the Waste Discharge Identification (WDID) confirmation. 1.3 SWPPP AVAILABILITY AND IMPLEMENTATION The discharger shall make the SWPPP available at the construction site during working hours (see Section 7.5 of CSMP for working hours) while construction is occurring and shall be made available upon request by a State or Municipal inspector. When the original SWPPP is retained by a crewmember in a construction vehicle and is not currently at the construction site, current copies of the BMPs and map/drawing will be left with the field crew and the original SWPPP shall be made available via request by radio/telephone. (CGP Section XIV.C) The SWPPP shall be implemented concurrently with the start of ground disturbing activities. 1.4 SWPPP AMENDMENTS The SWPPP should be revised when: · If there is a General Permit violation. · There is a reduction or increase in total disturbed acreage (General Permit Section II Part C). · BMPs do not meet the objectives of reducing or eliminating pollutants in stormwater discharges. Additionally, the SWPPP shall be amended when: · There is a change in construction or operations which may affect the discharge of pollutants to surface waters, groundwater(s), or a municipal separate storm sewer system (MS4); · There is a change in the project duration that changes the project’s risk level; or · When deemed necessary by the QSD. The QSD has determined that the changes listed in Table 1.1 can be field determined by the QSP. All other changes shall be made by the QSD as formal amendments to the SWPPP. The following items shall be included in each amendment: · Who requested the amendment; · The location of proposed change; · The reason for change; · The original BMP proposed, if any; and · The new BMP proposed. Amendment shall be logged at the front of the SWPPP and certification kept in Appendix D. The SWPPP text shall be revised replaced and/or hand annotated as necessary to properly convey the amendment. SWPPP amendments must be made by a QSD. The following changes have been designated by the QSD as “to be field determined” and constitute minor changes that the QSP may implement based on field conditions. Alexan Arcadia 6 December 2023 Table 1.1 List of Changes to be Field Determined Candidate changes for field location or determination by QSP (1) Check changes that can be field located or field determined by QSP Increase quantity of an Erosion or Sediment Control Measure X Relocate/add stockpiles or stored materials X Relocate or add toilets X Relocate vehicle storage and/or fueling locations X Relocate areas for waste storage X Relocate water storage and/or water transfer location X Changes to access points (entrance/exits) X Change type of Erosion or Sediment Control Measure X Changes to location of erosion or sediment control X Minor changes to schedule or phases X Changes in construction materials X (1) Any field changes not identified for field location or field determination by QSP must be approved by QSD 1.5 RETENTION OF RECORDS Paper or electronic records of documents required by this SWPPP shall be retained for a minimum of three years from the date generated or date submitted, whichever is later, for the following items: · Inspection Records · SWPPP Amendments · Violations These records shall be available at the Site until construction is complete. Records assisting in the determination of compliance with the General Permit shall be made available within a reasonable time to the Regional Water Board, State Water Board, or U.S. Environmental Protection Agency (EPA) upon request. Requests by the Regional Water Board for retention of records for a period longer than three years shall be adhered to. Alexan Arcadia 7 December 2023 1.6 REQUIRED NON-COMPLIANCE REPORTING If a General Permit discharge violation occurs, the QSP shall immediately notify the LRP. The LRP shall include information on the violation with the Annual Report. Corrective measures will be implemented immediately following identification of the discharge or written notice of non-compliance from the Regional Water Board. Discharges and corrective actions must be documented and include the following items: · The date, time, location, nature of operation and type of unauthorized discharge. · The cause or nature of the notice or order. · The BMPs deployed before the discharge event, or prior to receiving notice or order. · The date of deployment and type of BMPs deployed after the discharge event, or after receiving the notice or order, including additional measures installed or planned to reduce or prevent re-occurrence. Reporting requirements for NALs exceedances are discussed in Section 7.7.2.7. 1.7 ANNUAL REPORT The General Permit requires that permittees prepare, certify, and electronically submit an Annual Report no later than September 1 of each year. Reporting requirements are identified in Section XVI of the General Permit. Annual reports will be filed in SMARTS and in accordance with information required by the online forms. 1.8 CHANGES TO PERMIT COVERAGE The General Permit allows for the reduction or increase of the total acreage covered under the General Permit when: a portion of the project is complete and/or conditions for termination of coverage have been met (see Section 1.9); when ownership of a portion of the project is purchased by a different entity; or when new acreage is added to the project. Modified PRDs shall be filed electronically within 30 days of a reduction or increase in total disturbed area if a change in permit-covered acreage is to be sought. The SWPPP shall be modified appropriately and shall be logged at the front of the SWPPP and certification of SWPPP amendments are to be kept in Appendix D. Updated PRDs submitted electronically via SMARTS can be found in Appendix E. 1.9 NOTICE OF TERMINATION A Notice of Termination (NOT) must be submitted electronically by the LRP via SMARTS to terminate coverage under the General Permit. According to the requirements of Section II.D.1 of the General Permit, the following method will be used to satisfy final cover requirements: The NOT must include a final Site Map and representative photographs of the project site that demonstrate final stabilization has been achieved. The NOT shall be submitted within 90 days of construction completion. The Regional Water Board will consider a construction site complete when the conditions of the General Permit, Section II.D, have been met. Alexan Arcadia 8 December 2023 Section 2 Project Information 2.1 PROJECT AND SITE DESCRIPTION 2.1.1 Site Description The Alexan Arcadia project site comprises approximately 2.13 acres and is located at 34 E Santa Clara Street in the City of Arcadia, California. The Alexan Arcadia project is located on the west side of Santa Anita Avenue, south of E Santa Clara Street and north of Wheeler Avenue. It is also located south of HWY 210 (Foothill Freeway), at 34.14223 Lat/-118.03038 Long and is identified on the Site Map in Appendix B. 2.1.2 Existing Conditions The project site is currently a paved parking lot surrounded by single and double-story commercial buildings. Vegetation consists of some isolated trees and shrubs in some planter islands. 2.1.3 Existing Drainage The site slopes gently to the south with an elevation change of approximately 7 feet at an approximate grade of 1.6%. Surface runoff flows south to the street gutter and enters the county storm drain system at the northeast intersection of Wheeler Avenue and Santa Anita Avenue. The storm drain network connects to Arcadia Wash which is a reinforced concrete lined channel less than a mile southwest downstream from the site. The eventual receiving water for the stormwater runoff is the Rio Hondo Reach 3 river at El Monte. This is a concrete-lined channel which is listed for water quality impairment within Section 303(d) of the Clean Water Act (CWA), aka 303(d) list, from the following pollutants: · Indicator Bacteria · Iron · Oxygen, Dissolved 2.1.4 Geology and Groundwater The site is underlain by artificial fill and Holocene age alluvium comprised of alluvial channel and outwash deposits consisting of varying amounts of silt, sand, and gravel (California Geological Survey [CGS], 2010). Historical highest groundwater level in the immediate area is approximately, 100 to 150 feet beneath the ground surface; however, it was not encountered when boring to 40 feet was undertaken. 2.1.5 Project Description Project grading will occur on 2.13 acres of the project, which comprises the whole site area. Grading will include both cut and fill activities, with the total graded material estimated to be 65,300 cubic yards. Approximately 65,100 cubic yards of soil material will be exported during grading activities. 2.1.6 Developed Condition Post-construction surface runoff will be collected via area drains that connect to the underground network which will discharge to a dry well located behind the proposed driveway crossing to Wheeler Avenue. Roof drains will be piped to the dry well system below the basement level. Overflows from the dry wells discharge to the street gutter in Wheeler Avenue Alexan Arcadia 9 December 2023 which will enter the county storm drain network via the catch basin at the northeast curb return intersection with Santa Anita Avenue. The county storm drain network connects to Arcadia Wash which eventually discharges to Rio Hondo Channel in El Monte. Post-construction drainage patterns and conveyance systems are presented on Grading Plan – Sheets C310 – C314 in Appendix B. Table 2.1 Construction Site Estimates Construction site area 2.13 acres Percent impervious before construction 95 % Runoff coefficient before construction 0.95 Percent impervious after construction 95 % Runoff coefficient after construction 0.95 2.2 PERMITS AND GOVERNING DOCUMENTS In addition to the General Permit, the following documents have been taken into account while preparing this SWPPP: · Regional Water Board requirements · Basin Plan requirements · Contract Documents · Air Quality Regulations and Permits · Federal Endangered Species Act · National Historic Preservation Act/Requirements of the State Historic Preservation Office · State of California Endangered Species Act · Clean Water Act Section 401 Water Quality Certifications and 404 Permits · CA Department of Fish and Game 1600 Streambed Alteration Agreement 2.3 STORMWATER RUN-ON FROM OFFSITE AREAS There is no anticipated offsite run-on to this construction site. 2.4 FINDINGS OF THE CONSTRUCTION SITE SEDIMENT AND RECEIVING WATER RISK DETERMINATION A construction site risk assessment has been performed for the project and the resultant risk level is Risk Level 1 Alexan Arcadia 10 December 2023 The risk level was determined through the use of the K and LS factors provided in SMARTS and the EPA website was used to determine the R factor. The risk level is based on project duration, location, proximity to impaired receiving waters and soil conditions. A copy of the Risk Level determination submitted on SMARTS with the PRDs is included in Appendix C. Table 2.2 and Table 2.3 summarize the sediment and receiving water risk factors and document the sources of information used to derive the factors. Table 2.2 Summary of Sediment Risk RUSLE Factor Value Method for establishing value R 163.91 https://lew.epa.gov/ K 0.32 SMARTS (weighted average, by area, for all site soils) LS 0.25 SMARTS (weighted average, by area, for all slopes) Total Predicted Sediment Loss (tons/acre) 13.11 Overall Sediment Risk Low Sediment Risk < 15 tons/ acre Medium Sediment Risk >= 15 and < 75 tons/acre High Sediment Risk >= 75 tons/acre Low Medium High Runoff from the project site discharges into an existing concrete channel on the southwest side of the project site that eventually discharges into Arcadia Wash. Table 2.3 Summary of Receiving Water Risk Receiving Water Name 303(d) Listed for Sediment Related Pollutant (1) TMDL for Sediment Related Pollutant (1) Beneficial Uses of COLD, SPAWN, and MIGRATORY (1) Rio Hondo Channel Yes No Yes No Yes No Overall Receiving Water Risk Low High (1) If yes is selected for any option the Receiving Water Risk is High Risk Level 1 sites are subject to the narrative effluent limitations specified in the General Permit. The narrative effluent limitations require stormwater discharges associated with construction activity to minimize or prevent pollutants in stormwater and authorized non-stormwater through the use of controls, structures, and best management practices. This SWPPP has been prepared to address Risk Level 1 requirements (General Permit Attachment C). Alexan Arcadia 11 December 2023 2.5 CONSTRUCTION SCHEDULE The site sediment risk was determined based on construction taking place between December 1, 2023 and July 1, 2024. Modification or extension of the schedule (start and end dates) may affect risk determination and permit requirements. The LRP shall contact the QSD if the schedule changes during construction to address potential impact to the SWPPP. The estimated schedule for planned work can be found in Appendix F. 2.6 POTENTIAL CONSTRUCTION ACTIVITY AND POLLUTANT SOURCES Appendix G includes a list of construction activities and associated materials that are anticipated to be used onsite. These activities and associated materials will or could potentially contribute pollutants, other than sediment, to stormwater runoff. The anticipated activities and associated pollutants were used in Section 3 to select the Best Management Practices for the project. Locations of anticipated pollutants and associated BMPs are shown on the Site Map in Appendix B. For sampling requirements for non-visible pollutants associated with construction activity, please refer to Section 7.7.1. For a full and complete list of onsite pollutants, refer to the Safety Data Sheets (SDS), which are retained onsite at the construction trailer. 2.7 IDENTIFICATION OF NON-STORMWATER DISCHARGES Non-stormwater discharges consist of discharges which do not originate from precipitation events. The General Permit provides allowances for specified non-stormwater discharges that do not cause erosion or carry other pollutants. Non-stormwater discharges into storm drainage systems or waterways, which are not authorized under the General Permit and listed in the SWPPP, or authorized under a separate NPDES permit, are prohibited. Non-stormwater discharges that are authorized from this project site include the following: · Irrigation of vegetative erosion control measures · Water for dust control These authorized non-stormwater discharges will be managed with the stormwater and non- stormwater BMPs described in Section 3 of this SWPPP and will be minimized by the QSP. Activities at this site that may result in unauthorized non-stormwater discharges include: · Vehicle and equipment cleaning, fueling and maintenance operations; · Vehicle and equipment wash water, including concrete washout water; · Slurries from concrete or mortar mixing operations; · Slurries from drilling or boring operations; · Runoff from dust control applications of water or dust palliatives; · Chemical leaks and/or spills of any kind including but not limited to petroleum, · Paints, cure compounds, etc. Alexan Arcadia 12 December 2023 Steps will be taken, including the implementation of appropriate BMPs, to ensure that unauthorized discharges are eliminated, controlled, disposed, or treated on-site. Discharges of construction materials and wastes, such as fuel or paint, resulting from dumping, spills, or direct contact with rainwater or stormwater runoff, are also prohibited. 2.8 REQUIRED SITE MAP INFORMATION The construction project’s Site Map(s) showing the project location, surface water boundaries, geographic features, construction site perimeter and general topography and other requirements identified in Attachment B of the General Permit is located in Appendix B. Table 2.5 identifies Map or Sheet Nos. where required elements are illustrated. Table 2.5 Required Map Information Included on Map/Plan Sheet No. (1) Required Element Erosion Control Plan The project’s surrounding area (vicinity) Erosion Control Plan Site layout Erosion Control Plan Construction site boundaries Erosion Control Plan Drainage areas Erosion Control Plan Discharge locations Erosion Control Plan Sampling locations Erosion Control Plan Areas of soil disturbance (temporary or permanent) Erosion Control Plan Active areas of soil disturbance (cut or fill) Erosion Control Plan Locations of runoff BMPs Erosion Control Plan Locations of erosion control BMPs Erosion Control Plan Locations of sediment control BMPs Erosion Control Plan ATS location (if applicable) Erosion Control Plan Locations of sensitive habitats, watercourses, or other features which are not to be disturbed Erosion Control Plan Locations of all post-construction BMPs Erosion Control Plan Waste storage areas Erosion Control Plan Vehicle storage areas Erosion Control Plan Material storage areas Erosion Control Plan Entrance and Exits Notes: (1) Indicate maps or drawings that information is included on (e.g., Vicinity Map, Site Map, Drainage Plans, Grading Plans, Progress Maps, etc.) Alexan Arcadia 13 December 2023 Section 3 Best Management Practices 3.1 SCHEDULE FOR BMP IMPLEMENTATION Table 3.1 BMP Implementation Schedule BMP Implementation Duration Er o s i o n Co n t r o l EC-1, Scheduling Prior to Construction Entirety of Project EC-2, Preservation of Existing Vegetation Start of Construction Entirety of Project EC-9, Earth Dikes and Drainage Swales Prior to land disturbance Grading Phase Se d i m e n t C o n t r o l SE-1, Silt Fence Prior to Construction Entirety of Project SE-5, Fiber Rolls Prior to Construction Entirety of Project SE-6, Gravel Bag Berm Prior to Construction Entirety of Project SE-7, Street Sweeping & Vacuuming Prior to Construction Entirety of Project Tr a c k i n g Co n t r o l TC-1, Stabilized Construction Entrance Prior to land disturbance Grading Phase TC-3, Entrance/Outlet Tire Wash Prior to land disturbance Grading Phase Wa s t e M a n a g e m e n t & M a t e r i a l s Po l l u t i o n C o n t r o l WM-1, Material Delivery and Storage Start of Construction Entirety of Project WM-4, Spill Prevention & Control Start of Construction Entirety of Project WM-5, Solid Waste Management Prior to Construction Entirety of Project WM-8, Concrete Waste Management Prior to Construction Entirety of Project WM-9, Sanitary/Septic Waste Management Prior to Construction Entirety of Project Alexan Arcadia 14 December 2023 Table 3.1 BMP Implementation Schedule BMP Implementation Duration Wi n d Er o s i o n Wind Erosion Control Prior to land disturbance Grading Phase 3.2 EROSION AND SEDIMENT CONTROL Erosion and sediment controls are required by the General Permit to provide effective reduction or elimination of sediment related pollutants in stormwater discharges and authorized non- stormwater discharges from the Site. Applicable BMPs are identified in this section for erosion control, sediment control, tracking control, and wind erosion control. 3.2.1 Erosion Control Erosion control, also referred to as soil stabilization, consists of source control measures that are designed to prevent soil particles from detaching and becoming transported in stormwater runoff. Erosion control BMPs protect the soil surface by covering and/or binding soil particles. This construction project will implement the following practices to provide effective temporary and final erosion control during construction: 1. Preserve existing vegetation where required and when feasible. 2. The area of soil disturbing operations shall be controlled such that the Contractor is able to implement erosion control BMPs quickly and effectively. 3. Stabilize non-active areas within 14 days of cessation of construction activities or sooner if stipulated by local requirements. 4. Control erosion in concentrated flow paths by applying erosion control blankets, check dams, erosion control seeding, or alternate methods. 5. Prior to the completion of construction, apply permanent erosion control to remaining disturbed soil areas. Sufficient erosion control materials shall be maintained onsite to allow implementation in conformance with this SWPPP. The following erosion control BMP selection table, Table 3.2 indicates the BMPs that shall be implemented to control erosion on the construction site. Fact Sheets for temporary erosion control BMPs are provided in Appendix H. These temporary erosion control BMPs shall be implemented in conformance with the following guidelines and as outlined in the BMP Factsheets provided in Appendix H. If there is a conflict between documents, the Site Map will prevail over narrative in the body of the SWPPP or guidance in the BMP Fact Sheets. Site specific details in the Site Map prevail over standard details included in the Site Map. The narrative in the body of the SWPPP prevails over guidance in the BMP Fact Sheets. Scheduling Scheduling of construction activities shall be implemented by the contractor to reduce the potential for sediment/pollutants being transported off the project site. This is a site wide BMP that shall be implemented for the duration of the project. Alexan Arcadia 15 December 2023 Wind Erosion Control Wind erosion control shall be implemented onsite by the contractor for the duration of the project and especially during grading operations. The BMP shall be implemented as needed to prevent wind from transporting sediment/dust offsite. Alexan Arcadia 16 December 2023 Table 3.2 Erosion Control BMPs CASQ A Fact Sheet BMP Name Considered for the Project (1) BMP Used If not used, state reason and alternate BMP, if applicable YES NO EC-1 Scheduling  X EC-2 Preservation of Existing Vegetation  X EC-3 Hydraulic Mulch (2) X Will be used if needed. Vegetation will be maintained where possible EC-4 Hydroseed (2) X As needed EC-5 Soil Binders (2) X As needed EC-6 Straw Mulch (2) X As needed EC-7 Geotextiles and Mats (2) X As needed. EC-8 Wood Mulching (2) X Will use hydraulic mulch if needed. EC-9 Earth Dike and Drainage Swales (3) X EC-10 Velocity Dissipation Devices (3) X None needed due to flat site EC-11 Slope Drains (3) X No slopes present EC-12 Stream Bank Stabilization X No stream banks present. EC-14 Compost Blankets (2) X Should not be needed EC-15 Soil Preparation-Roughening X EC-16 Non-Vegetated Stabilization (2) X WE-1 Wind Erosion Control  X (1) The General Permit’s Fact Sheet Section II.J.1.c through II.J.1.g describes various BMPs that should be considered for use on the construction site. (2) The QSD shall ensure implementation of one of the minimum measures listed or a combination thereof to achieve and maintain the Risk Level requirements. (3) All run-on and runoff from the construction site shall be managed for LUP Types 2 and 3 and LUP Type 1 if the evaluation of quantity and quality of run-on and runoff deems them necessary or visual inspections show that the site requires these controls. Run-on from offsite shall be directed away from all disturbed areas, diversion of offsite flows may require design/analysis by a licensed civil engineer and/or additional environmental permitting. Alexan Arcadia 17 Decemeber 2023 These temporary erosion control BMPs shall be implemented in conformance with the following guidelines and as outlined in the BMP Factsheets provided in Appendix H. If there is a conflict between documents, the Site Map will prevail over narrative in the body of the SWPPP or guidance in the BMP Fact Sheets. Site specific details in the Site Map prevail over standard details included in the Site Map. The narrative in the body of the SWPPP prevails over guidance in the BMP Fact Sheets. Scheduling Scheduling of construction activities shall be implemented by the contractor to reduce the potential for sediment/pollutants being transported off the project site. This is a site wide BMP that shall be implemented for the duration of the project. Wind Erosion Control Wind erosion control shall be implemented onsite by the contractor for the duration of the project and especially during grading operations. The BMP shall be implemented as needed to prevent wind from transporting sediment/dust offsite. 3.2.2 Sediment Controls Sediment controls are temporary or permanent structural measures that are intended to complement the selected erosion control measures and reduce sediment discharges from active construction areas. Sediment controls are designed to intercept and settle out soil particles that have been detached and transported by the force of water. The following sediment control BMP selection table indicates the BMPs that shall be implemented to control sediment on the construction site. Fact Sheets for temporary sediment control BMPs are provided in Appendix H. Alexan Arcadia 18 December 2023 Table 3.3 Temporary Sediment Control BMPs CASQ A Fact Sheet BMP Name Considered for the Project (1) BMP used If not used, state reason and alternate BMP, if applicable YES NO SE-1 Silt Fence (2) (3) X SE-2 Sediment Basin X Not needed. SE-3 Sediment Trap X Not needed. SE-4 Check Dams X Not needed. SE-5 Fiber Rolls (2)(3) X SE-6 Gravel Bag Berm (3) X SE-7 Street Sweeping  X SE-8 Sandbag Barrier X Gravel bag berm will be used SE-9 Straw Bale Barrier X Gravel bag berm will be used SE-10 Storm Drain Inlet Protection  RL2&3 X SE-11 ATS X Not needed. SE-12 Manufactured Linear Sediment Controls X Not needed. SE-13 Compost Sock and Berm (3) X Not needed. SE-14 Biofilter Bags (3) X Not needed. TC-1 Stabilized Construction Entrance and Exit  X TC-2 Stabilized Construction Roadway X TC-1 will be used TC-3 Entrance Outlet Tire Wash X (1) The General Permit’s Fact Sheet Section II.J.1.c through II.J.1.g describes various BMPs that should be considered for use on the construction site. (2) The QSD shall ensure implementation of one of the minimum measures listed or a combination thereof to achieve and maintain the Risk Level requirements. (3) All run-on and runoff from the construction site shall be managed. Risk Level 2 &3 shall provide linear sediment control along toe of slope, face of slope, and at the grade breaks of exposed slope. Alexan Arcadia 19 December 2023 These temporary sediment control BMPs shall be implemented in conformance with the following guidelines and in accordance with the BMP Fact Sheets provided in Appendix H. If there is a conflict between documents, the Site Map will prevail over narrative in the body of the SWPPP or guidance in the BMP Fact Sheets. Site specific details in the Site Map prevail over standard details included in the Site Map. The narrative in the body of the SWPPP prevails over guidance in the BMP Fact Sheets. Silt Fence Silt fence can be used onsite as a perimeter control device. This BMP shall be implemented by the QSP and/or contractor during the project duration. The BMP shall be maintained as needed to ensure it is functioning properly. Sediment shall be removed prior to reaching to 1/3 of the barrier height. Check Dams A check dam is a small barrier constructed of rock, gravel bags, sandbags, fiber rolls, or other proprietary products, placed across a constructed swale or drainage ditch. Check dams reduce the effective slope of the channel, thereby reducing scour and channel erosion by reducing flow velocity and increasing residence time within the channel, allowing sediment to settle. Gravel Bag Berm Gravel bag berm can be used onsite as a perimeter control device. This BMP shall be implemented by the QSP and/or contractor during the project duration. The BMP shall be maintained as needed to ensure it is functioning properly. Stabilized Construction Entrance and Exit Stabilized construction entrances/exits shall be provided by the contractor at each vehicle entrance/exit to the site. They should be maintained monthly or more frequently if needed and be implemented until the site is stabilized. Entrance Outlet Tire Wash A tire wash is an area located at stabilized construction access points to remove sediment from tires and under carriages and to prevent sediment from being transported onto public roadways. Alexan Arcadia 20 December 2023 3.3 NON-STORMWATER CONTROLS AND WASTE AND MATERIALS MANAGEMENT 3.3.1 Non-Stormwater Controls Non-stormwater discharges into storm drainage systems or waterways which are not authorized under the General Permit are prohibited. Non-stormwater discharges for which a separate NPDES permit is required by the local Regional Water Board are prohibited unless coverage under the separate NPDES permit has been obtained for the discharge. The selection of non- stormwater BMPs is based on the list of construction activities with a potential for non- stormwater discharges identified in Section 2.7 of this SWPPP. The following non-stormwater control BMP selection table indicates the BMPs that shall be implemented to control sediment on the construction site. Fact Sheets for temporary non- stormwater control BMPs are provided in Appendix H. Non-stormwater BMPs shall be implemented in conformance with the following guidelines and in accordance with the BMP Fact Sheets provided in Appendix H. If there is a conflict between documents, the Site Map will prevail over narrative in the body of the SWPPP or guidance in the BMP Fact Sheets. Site specific details in the Site Map prevail over standard details included in the Site Map. The narrative in the body of the SWPPP prevails over guidance in the BMP Fact Sheets. Alexan Arcadia 21 December 2023 Table 3.4 Temporary Non-Stormwater BMPs CASQA Fact Sheet BMP Name Considered for the Project (1) BMP used If not used, state reason and alternate BMP, if applicable YES NO NS-1 Water Conservation Practices  X NS-2 Dewatering Operation  X NS-3 Paving and Grinding Operation X NS-4 Temporary Stream Crossing X No streams present. NS-5 Clear Water Diversion X No run-on present NS-6 Illicit Connection/Discharge  X NS-7 Potable Water/Irrigation X NS-8 Vehicle and Equipment Cleaning  X NS-9 Vehicle and Equipment Fueling  X NS-10 Vehicle and Equipment Maintenance  X Equipment not to be maintained on site NS-11 Pile Driving Operation X NS-12 Concrete Curing X NS-13 Concrete Finishing X NS-14 Material and Equipment Use Over Water X No water present. NS-15 Demolition Removal Adjacent to Water X No water present. NS-16 Temporary Batch Plants X None needed. (1) The General Permit’s Fact Sheet Section II.J.1.c through II.J.1.g describes various BMPs that should be considered for use on the construction site. Alexan Arcadia 22 December 2023 3.3.2 Materials Management and Waste Management Materials management control practices consist of implementing procedural and structural BMPs for handling, storing, and using construction materials to prevent the release of those materials into stormwater discharges. The amount and type of construction materials to be utilized at the Site will depend upon the type of construction and the length of the construction period. The materials may be used continuously, such as fuel for vehicles and equipment, or the materials may be used for a discrete period, such as soil binders for temporary stabilization. Waste management consist of implementing procedural and structural BMPs for handling, storing, and ensuring proper disposal of wastes to prevent the release of those wastes into stormwater discharges. Materials and waste management pollution control BMPs shall be implemented to minimize stormwater contact with construction materials, wastes and service areas; and to prevent materials and wastes from being discharged off-site. The primary mechanisms for stormwater contact that shall be addressed include: · Direct contact with precipitation · Contact with stormwater run-on and runoff · Wind dispersion of loose materials · Direct discharge to the storm drain system through spills or dumping · Extended contact with some materials and wastes, such as asphalt cold mix and treated wood products, which can leach pollutants into stormwater. A list of construction activities is provided in Section 2.6. The following Materials and Waste Management BMP selection table, Table 3.5, indicates the BMPs that shall be implemented to handle materials and control construction site wastes associated with these construction activities. Fact Sheets for Materials and Waste Management BMPs are provided in Appendix H. Material management BMPs shall be implemented in conformance with the following guidelines and in accordance with the BMP Fact Sheets provided in Appendix H. If there is a conflict between documents, the Site Map will prevail over narrative in the body of the SWPPP or guidance in the BMP Fact Sheets. Site specific details in the Site Map prevail over standard details included in the Site Map. The narrative in the body of the SWPPP prevails over guidance in the BMP Fact Sheets. Alexan Arcadia 23 December 2023 Table 3.5 Temporary Materials Management BMPs CASQA Fact Sheet BMP Name Considered for Project (1) BMP used If not used, state reason and alternate BMP, if applicable YES NO WM-01 Material Delivery and Storage  X WM-02 Material Use  X WM-03 Stockpile Management  X WM-04 Spill Prevention and Control  X WM-05 Solid Waste Management  X WM-06 Hazardous Waste Management  X WM-07 Contaminated Soil Management X WM-08 Concrete Waste Management  X WM-09 Sanitary-Septic Waste Management  X WM-10 Liquid Waste Management X (1) The General Permit’s Fact Sheet Section II.J.1.c through II.J.1.g describes various BMPs that should be considered for use on the construction site. Alexan Arcadia 24 December 2023 3.4 POST CONSTRUCTION STORMWATER MANAGEMENT MEASURES Post construction BMPs are permanent measures installed during construction, designed to reduce or eliminate pollutant discharges from the site after construction is completed. This site is located in an area subject to a Phase I or Phase II Municipal Separate Storm Sewer System (MS4) permit approved Stormwater Management Plan. Yes No Post construction runoff reduction requirements have been satisfied through the MS4 program, this project is exempt from provision XIII A of the General Permit.] A plan for the post construction funding and maintenance of these BMPs has been developed to address at minimum five years following construction. The post construction BMPs that are described above shall be funded and maintained by the LRP. If required, post construction funding and maintenance will be submitted with the NOT. Alexan Arcadia 25 December 2023 Section 4 BMP Inspection, Maintenance, and Rain Event Action Plans 4.1 BMP INSPECTION AND MAINTENANCE The General Permit requires routine weekly inspections of BMPs, along with inspections before, during, and after qualifying rain events. A BMP inspection checklist must be filled out for inspections and maintained on-site onsite with the SWPPP. The inspection checklist includes the necessary information covered in Section 7.6. A blank inspection checklist can be found in Appendix I. Completed checklists shall be kept in CSMP Appendix P “Monitoring Records”. BMPs shall be maintained regularly to ensure proper and effective functionality. If necessary, corrective actions shall be implemented within 72 hours of identified deficiencies and associated amendments to the SWPPP shall be prepared by the QSD. Specific details for maintenance, inspection, and repair of Construction Site BMPs can be found in the BMP Factsheets in Appendix H. 4.2 RAIN EVENT ACTION PLANS Rain Event Action Plans (REAPs) are not required for Risk Level 1 projects. Alexan Arcadia 26 December 2023 Section 5 Training Appendix L identifies the QSPs for the project. To promote stormwater management awareness specific for this project, periodic training of job-site personnel shall be included as part of routine project meetings (e.g. daily/weekly tailgate safety meetings), or task specific trainings as needed. The QSP shall be responsible for providing this information at the meetings, and subsequently completing the training logs shown in Appendix K, which identify the site-specific stormwater topics covered as well as the names of site personnel who attended the meeting. Tasks may be delegated to trained employees by the QSP provided adequate supervision and oversight is provided. Training shall correspond to the specific tasks delegated, including SWPPP implementation, BMP inspection and maintenance, and recordkeeping. Documentation of training activities (formal and informal) is retained in SWPPP Appendix K. Alexan Arcadia 27 December 2023 Section 6 Responsible Parties and Operators 6.1 RESPONSIBLE PARTIES Approved Signatory who are responsible for SWPPP implementation and have authority to sign permit-related documents is listed below. Written authorizations from the LRP for these individuals are provided in Appendix L. The Approved Signatory assigned to this project is: Name Title Phone Number Todd Phillips LRP (760) 444 5213 Leah Isidro QSD (661) 705 4425 QSPs identified for the project are identified in Appendix L. The QSP shall have primary responsibility and significant authority for the implementation, maintenance, and inspection/monitoring of SWPPP requirements. The QSP will be available at all times throughout the duration of the project. Duties of the QSP include but are not limited to: · Implementing all elements of the General Permit and SWPPP, including, but not limited to: o Ensuring that all BMPs are implemented, inspected, and properly maintained; o Performing non-stormwater and stormwater visual observations and inspections; o Performing non-stormwater and storm sampling and analysis, as required; o Performing routine inspections and observations; o Implementing non-stormwater management, and materials and waste management activities such as: monitoring discharges; general Site clean-up; vehicle and equipment cleaning, fueling and maintenance; spill control; ensuring that no materials other than stormwater are discharged in quantities which will have an adverse effect on receiving waters or storm drain systems, etc.; · The QSP may delegate these inspections and activities to an appropriately trained employee but shall ensure adequacy and adequate deployment. · Ensuring elimination of unauthorized discharges. · The QSPs shall be assigned authority by the LRP to mobilize crews in order to make immediate repairs to the control measures. · Coordinate with the Contractor(s) to assure all of the necessary corrections/repairs are made immediately and that the project complies with the SWPPP, General Permit, and approved plans at all times. · Notifying the LRP or Authorized Signatory immediately of off-site discharges or other non-compliance events Alexan Arcadia 28 December 2023 6.2 CONTRACTOR LIST Contractor Name: Title: Company: Address: Phone Number: Number (24/7): Alexan Arcadia 29 December 2023 Section 7 Construction Site Monitoring Program 7.1 Purpose This Construction Site Monitoring Program was developed to address the following objectives: 1. To demonstrate that the site is in compliance with the Discharge Prohibitions of the Construction General Permit; 2. To determine whether non-visible pollutants are present at the construction site and are causing or contributing to exceedances of water quality objectives; 3. To determine whether immediate corrective actions, additional Best Management Practices (BMP) implementation, or SWPPP revisions are necessary to reduce pollutants in stormwater discharges and authorized non-stormwater discharges; 4. To determine whether BMPs included in the SWPPP are effective in preventing or reducing pollutants in stormwater discharges and authorized non-stormwater discharges. 7.2 Applicability of Permit Requirements This project has been determined to be a Risk Level 1 project. The General Permit identifies the following types of monitoring as being applicable for a Risk Level 1 project. Risk Level 1 · Visual inspections of BMPs; · Visual monitoring of the site related to qualifying storm events; · Visual monitoring of the site for non-stormwater discharges; · Sampling and analysis of construction site runoff for non-visible pollutants when applicable; and · Sampling and analysis of construction site runoff as required by the Regional Water Board when applicable. 7.3. Weather and Rain Event Tracking Visual monitoring and inspections requirements of the General Permit are triggered by a qualifying rain event. The General Permit defines a qualifying rain event as any event that produces ½ inch of precipitation. A minimum of 48 hours of dry weather will be used to distinguish between separate qualifying storm events. 7.3.1 Weather Tracking The QSP should daily consult the National Oceanographic and Atmospheric Administration (NOAA) for the Forecast Weather Table Interface. These forecasts can be obtained at http://forecast.weather.gov . Weather reports should be printed and maintained with the SWPPP in Appendix O “Weather Reports”. 7.3.2 Rain Gauges The QSP shall install (1) rain gauge(s) on the project site. Locate the gauge in an open area away from obstructions such as trees or overhangs. Mount the gauge on a post at a height of 3 to 5 feet with the gauge extending several inches beyond the post. Make sure that the top of the gauge is level. Make sure the post is not in an area where rainwater can indirectly splash from sheds, equipment, trailers, etc. Alexan Arcadia 30 December 2023 The rain gauge(s) shall be read daily during normal site scheduled hours. The rain gauge should be read at approximately the same time every day and the date and time of each reading recorded. Log rain gauge readings in Appendix O “Weather Records”. Follow the rain gauge instructions to obtain accurate measurements. Once the rain gauge reading has been recorded, accumulated rain shall be emptied, and the gauge reset. For comparison with the site rain gauge, the nearest appropriate governmental rain gauge(s) is located at Arcadia (FS 107). 34.0928 Lat, 118.0205 Long Elev 609.0 Monitoring locations are described in the Sections 7.6 and 7.7. Whenever changes in the construction site might affect the appropriateness of sampling locations, the sampling locations shall be revised accordingly. All such revisions shall be implemented as soon as feasible and the SWPPP amended. Temporary changes that result in a one-time additional sampling location do not require a SWPPP amendment. 7.5 Safety and Monitoring Exemptions Safety practices for sample collection will be in accordance with the Cal-OSHA. This project is not required to collect samples or conduct visual observations (inspections) under the following conditions: · During dangerous weather conditions such as flooding and electrical storms. · Outside of scheduled site business hours. Scheduled site business hours are: Monday to Friday 7am to 4pm. If monitoring (visual monitoring or sample collection) of the site is unsafe because of the dangerous conditions noted above, then the QSP shall document the conditions for why an exception to performing the monitoring was necessary. The exemption documentation shall be filed in Appendix P “Monitoring Records”. 7.6 Visual Monitoring Visual monitoring includes observations and inspections. Inspections of BMPs are required to identify and record BMPs that need maintenance to operate effectively, that have failed, or that could fail to operate as intended. Visual observations of the site are required to observe storm water drainage areas to identify any spills, leaks, or uncontrolled pollutant sources. Table 7.1 identifies the required frequency of visual observations and inspections. Inspections and observations will be conducted at the locations identified in Section 7.6.3. Table 7.1 Summary of Visual Monitoring and Inspections Type of Inspection Frequency Routine Inspections BMP Inspections Weekly1 BMP Inspections – Tracking Control Daily Non-Stormwater Discharge Observations Quarterly during daylight hours Rain Event Triggered Inspections Alexan Arcadia 31 December 2023 Table 7.1 Summary of Visual Monitoring and Inspections Type of Inspection Frequency Site Inspections Prior to a Qualifying Event Within 48 hours of a qualifying event 2 BMP Inspections During an Extended Storm Event Every 24-hour period of a rain event3 Site Inspections Following a Qualifying Event Within 48 hours of a qualifying event2 1 Most BMPs must be inspected weekly; those identified below must be inspected more frequently. 2 Inspections are required during scheduled site operating hours. 3 Inspections are required during scheduled site operating hours regardless of the amount of precipitation on any given day. 7.6.1 Routine Observations and Inspections Routine site inspections and visual monitoring are necessary to ensure that the project is in compliance with the requirements of the Construction General Permit. 7.6.1.1 Routine BMP Inspections Inspections of BMPs are conducted to identify and record: · BMPs that are properly installed; · BMPs that need maintenance to operate effectively; · BMPs that have failed; or · BMPs that could fail to operate as intended. 7.6.1.2 Non-Stormwater Discharge Observations Each drainage area will be inspected for the presence of or indications of prior unauthorized and authorized non-stormwater discharges. Inspections will record: · Presence or evidence of any non-stormwater discharge (authorized or unauthorized); · Pollutant characteristics (floating and suspended material, sheen, discoloration, turbidity, odor, etc.); and · Source of discharge. 7.6.2 Rain-Event Triggered Observations and Inspections Visual observations of the site and inspections of BMPs are required prior to a qualifying rain event; following a qualifying rain event, and every 24-hour period during a qualifying rain event. Pre-rain inspections will be conducted after consulting NOAA and determining that a precipitation event with a 50 percent or greater probability of precipitation has been predicted on the Forecast Weather Table Interface. 7.6.2.1 Visual Observations Prior to a Forecasted Qualifying Rain Event Within 48 hours prior to a qualifying event, a stormwater visual monitoring site inspection will include observations of the following locations: · Stormwater drainage areas to identify any spills, leaks, or uncontrolled pollutant sources; Alexan Arcadia 32 December 2023 · BMPs to identify if they have been properly implemented; · Any stormwater storage and containment areas to detect leaks and ensure maintenance of adequate freeboard. Consistent with guidance from the State Water Resources Control Board, pre-rain BMP inspections and visual monitoring will be triggered by a NOAA forecast that indicates a probability of precipitation of 50 percent or more in the project area. 7.6.2.2 BMP Inspections During an Extended Storm Event During an extended rain event BMP inspection will be conducted to identify and record: · BMPs that are properly installed; · BMPs that need maintenance to operate effectively; · BMPs that have failed; or · BMPs that could fail to operate as intended. If the construction site is not accessible during the rain event, the visual inspections shall be performed at all relevant outfalls, discharge points, downstream locations. The inspections should record any projected maintenance activities. 7.6.2.3 Visual Observations Following a Qualifying Rain Event Within 48 hours following a qualifying rain event (0.5 inches of rain), a stormwater visual monitoring site inspection is required to observe: · Stormwater drainage areas to identify any spills, leaks, or uncontrolled pollutant sources; · BMPs to identify if they have been properly designed, implemented, and effective; · Need for additional BMPs; · Any stormwater storage and containment areas to detect leaks and ensure maintenance of adequate freeboard; and · Discharge of stored or contained rain water. 7.6.3 Visual Monitoring Procedures Visual monitoring shall be conducted by the QSP or staff trained by and under the supervision of the QSP. The name(s) and contact number(s) of the site visual monitoring personnel are listed below and their training qualifications are provided in Appendix K. Assigned inspector: TBD Contact phone: TBD Alternate inspector: TBD Contact phone: TBD Stormwater observations shall be documented on the Visual Inspection Field Log Sheet (see Appendix Q “Example Forms”). BMP inspections shall be documented on the site-specific BMP inspection checklist. Any photographs used to document observations will be referenced on stormwater site inspection report and maintained with the Monitoring Records in Appendix P. The QSP shall within 2 days of the inspection submit copies of the completed inspection report to the Contractor. The completed reports will be kept in Appendix P “Monitoring Records”. Alexan Arcadia 33 December 2023 7.6.4 Visual Monitoring Follow-Up and Reporting Correction of deficiencies identified by the observations or inspections, including required repairs or maintenance of BMPs, shall be initiated and completed as soon as possible. If identified deficiencies require design changes, including additional BMPs, the implementation of changes will be initiated within 72 hours of identification and be completed as soon as possible. When design changes to BMPs are required, the SWPPP shall be amended to reflect the changes. Deficiencies identified in site inspection reports and correction of deficiencies will be tracked on the Inspection Field Log Sheet or BMP Inspection Report and shall be submitted to the QSP and shall be kept in Appendix P “Monitoring Records”. The QSP shall within 2 days of the inspection submit copies of the completed Inspection Field Log Sheet or BMP Inspection Report with the corrective actions to the contractor. Results of visual monitoring must be summarized and reported in the Annual Report. 7.6.5 Visual Monitoring Locations The inspections and observations identified in Sections 7.6.1 and 7.6.2 will be conducted at the locations identified in this section. BMP locations are shown on the Erosion & Sediment Control Plans in SWPPP Appendix B. There is only one (1) drainage areas on the project site and the contractor’s yard, staging areas, and storage areas. Drainage area is shown on the Erosion & Sediment Control Plans in Appendix B and Table 7.2 identifies each drainage area by location. Table 7.2 Site Drainage Areas Location No. Location 1 Drainage area discharging to Wheeler Avenue There are no stormwater storage or containment area(s) are on the project site. Stormwater storage or containment area(s) are shown on the Erosion & Sediment Control Plans in Appendix B and Table 7.3 identifies each stormwater storage or containment area by location. Table 7.3 Stormwater Storage and Containment Areas Location No. Location none There are 1 discharge location(s) on the project site. Site stormwater discharge location(s) are shown on the Erosion & Sediment Control Plans in Appendix B and Table 7.4 identifies each stormwater discharge location. Alexan Arcadia 34 December 2023 Table 7.4 Site Stormwater Discharge Locations Location No. Location 1 Southwest corner of site to Wheeler Avenue 7.7 Water Quality Sampling and Analysis 7.7.1 Sampling and Analysis Plan for Non-Visible Pollutants in Stormwater Runoff Discharges This Sampling and Analysis Plan for Non-Visible Pollutants describes the sampling and analysis strategy and schedule for monitoring non-visible pollutants in stormwater runoff discharges from the project site. Sampling for non-visible pollutants will be conducted when (1) a breach, leakage, malfunction, or spill is observed; and (2) the leak or spill has not been cleaned up prior to the rain event; and (3) there is the potential for discharge of non-visible pollutants to surface waters or drainage system. The following construction materials, wastes, or activities, as identified in Section 2.6, are potential sources of non-visible pollutants to stormwater discharges from the project. Storage, use, and operational locations are shown on the Erosion & Sediment Control Plans in Appendix B. · Demolition Activities · Paving Activities · Landscaping Activities · Painting Activities The following existing site features, as identified in Section 2.6, are potential sources of non- visible pollutants to stormwater discharges from the project. Locations of existing site features contaminated with non-visible pollutants are shown on the Site Maps in Appendix B. · NONE The following soil amendments have the potential to change the chemical properties, engineering properties, or erosion resistance of the soil and will be used on the project site. Locations of soil amendment application are shown on the Site Maps in Appendix B. · NONE Alexan Arcadia 35 December 2023 7.7.1.1 Sampling Schedule Samples for the potential non-visible pollutant(s) and a sufficiently large unaffected background sample shall be collected during the first two hours of discharge from rain events that result in a sufficient discharge for sample collection. Samples shall be collected during the site’s scheduled hours and shall be collected regardless of the time of year and phase of the construction. Collection of discharge samples for non-visible pollutant monitoring will be triggered when any of the following conditions are observed during site inspections conducted prior to or during a rain event. · Materials or wastes containing potential non-visible pollutants are not stored under watertight conditions. Watertight conditions are defined as (1) storage in a watertight container, (2) storage under a watertight roof or within a building, or (3) protected by temporary cover and containment that prevents stormwater contact and runoff from the storage area. · Materials or wastes containing potential non-visible pollutants are stored under watertight conditions, but (1) a breach, malfunction, leakage, or spill is observed, (2) the leak or spill is not cleaned up prior to the rain event, and (3) there is the potential for discharge of non-visible pollutants to surface waters or a storm drain system. · A construction activity, including but not limited to those in Section 2.6, with the potential to contribute non-visible pollutants (1) was occurring during or within 24 hours prior to the rain event, (2) BMPs were observed to be breached, malfunctioning, or improperly implemented, and (3) there is the potential for discharge of non-visible pollutants to surface waters or a storm drain system. · Soil amendments that have the potential to change the chemical properties, engineering properties, or erosion resistance of the soil have been applied, and there is the potential for discharge of non-visible pollutants to surface waters or a storm drain system. · Stormwater runoff from an area contaminated by historical usage of the site has been observed to combine with stormwater runoff from the site, and there is the potential for discharge of non-visible pollutants to surface waters or a storm drain system. 7.7.1.2 Sampling Locations Sampling locations are based on proximity to planned non-visible pollutant storage, occurrence or use, accessibility for sampling, and personnel safety. Planned non-visible pollutant sampling locations are shown on the Erosion & Sediment Control Plans in Appendix B. and include the locations identified in Tables 7.5 through 7.9. Two (2) sampling location(s) on the project site and the contractor’s yard have been identified for the collection of samples of runoff from planned material and waste storage areas and areas where non-visible pollutant producing construction activities are planned. 7.7.1.3 Monitoring Preparation Non-visible pollutant samples will be collected by: Contractor Yes No Consultant Yes No Alexan Arcadia 36 December 2023 Laboratory Yes No Samples on the project site will be collected by the following contractor sampling personnel: Name/Telephone Number: Alternate(s)/Telephone Number: An adequate stock of monitoring supplies and equipment for monitoring non-visible pollutants will be available on the project site prior to a sampling event. Monitoring supplies and equipment will be stored in a cool temperature environment that will not come into contact with rain or direct sunlight. Sampling personnel will be available to collect samples in accordance with the sampling schedule. Supplies maintained at the project site will include, but are not limited to, clean powder-free nitrile gloves, sample collection equipment, coolers, appropriate number and volume of sample bottles, identification labels, re-sealable storage bags, paper towels, personal rain gear, ice, and Effluent Sampling Field Log Sheets and Chain of Custody (CoC) forms, which are provided in Appendix Q “Example Forms”. Samples on the project site will be collected by the following: Company Name: Street Address: City, State Zip: Telephone Number: Point of Contact: Name of Sampler(s): Name of Alternate(s): The QSP or his/her designee will contact the aforementioned 24 hours prior to a predicted rain event or for an unpredicted event, as soon as a rain event begins if one of the triggering conditions is identified during an inspection to ensure that adequate sample collection personnel and supplies for monitoring non-visible pollutants are available and will be mobilized to collect samples on the project site in accordance with the sampling schedule. 7.7.1.4 Analytical Constituents Table 7.10 lists the specific sources and types of potential non-visible pollutants on the project site and the water quality indicator constituent(s) for that pollutant. Table 7.10 Potential Non-Visible Pollutants and Water Quality Indicator Constituents Pollutant Source/Pollutants Water Quality Indicator Constituent Adhesives COD, Phenols, SVOCs Asphalt Work VOCs Cleaning Alexan Arcadia 37 December 2023 Table 7.10 Potential Non-Visible Pollutants and Water Quality Indicator Constituents Pollutant Source/Pollutants Water Quality Indicator Constituent Acids pH Bleaches Residual chlorine TSP Phosphate Solvents VOCs, SVOCs Detergents MBAS Concrete / Masonry Work Sealant (Methyl methacrylate) SVOC Curing compounds VOCs, SVOCs, pH Ash, slag, sand pH, Al, Ca, Va, Zn Drywall Cu, Al, General Minerals Framing / Carpentry Treated Wood Cu, Cr, As, Zn Particle board Formaldehyde Untreated wood BOD Grading / Earthworks Gypsum / Lime amendments pH Contaminated Soil Constituents specific to known contaminants, check with Laboratory Heating, Ventilation, Air Conditioning Freon Insulation Al, Zn Landscaping Pesticides/Herbicides Product dependent, see label and check with Laboratory Fertilizers TKN, NO3, BOD, COD, DOC, Sulfate, NH3, Phosphate, Potassium Aluminum sulfate Al, TDS, Sulfate Liquid Waste Constituents specific to materials, check with Laboratory Painting Resins COD, SVOCs Thinners COD, VOCs Alexan Arcadia 38 December 2023 Table 7.10 Potential Non-Visible Pollutants and Water Quality Indicator Constituents Pollutant Source/Pollutants Water Quality Indicator Constituent Paint strippers VOCs, SVOCs, metals Lacquers, varnishes, enamels COD, VOCs, SVOCs Sealants COD Adhesives Phenols, SVOCs Planting / Vegetation Management Vegetation stockpiles BOD Fertilizers TKN, NO3, BOD, COD, DOC, sulfate, NH3, Phosphate, Potassium Pesticides/Herbicides Product dependent, see label and check with Laboratory Plumbing Solder, flux, pipe fitting Cu, Pb, Sn, Zn Pools and Fountains Residual chlorine, Cu, chloramines Removal of existing structures Zn, VOCs, PCBs (see also other applicable activity categories, e.g., grading, painting) Roofing Cu, Pb, VOCs Sanitary WasteSewer line breaks and Portable Toilets (using clear fluid – blue fluid is visible if discharged) BOD, Total/Fecal coliform Soil Preparation / Amendments/Dust Control Polymer/Co-polymers TKN, NO3, BOD, COD, DOC, Sulfate, Ni Lignin sulfate TDS, alkalinity Psyllium COD, TOC Guar/Plant Gums COD, TOC, Ni Solid Waste (leakage) BOD Utility Line Testing and Flushing Residual chlorine, chloramines Vehicle and Equipment Use Batteries Sulfuric acid; Pb, pH Alexan Arcadia 39 December 2023 7.7.1.5 Sample Collection Samples of discharge shall be collected at the designated non-visible pollutant sampling locations shown on the Erosion & Sediment Control Plans in Appendix B or in the locations determined by observed breaches, malfunctions, leakages, spills, operational areas, soil amendment application areas, and historical site usage areas that triggered the sampling event. Grab samples shall be collected and preserved in accordance with the methods identified in the Table 7.11, “Sample Collection, Preservation and Analysis for Monitoring Non-Visible Pollutants” provided in Section 7.7.1.6. Only the QSP, or personnel trained in water quality sampling under the direction of the QSP shall collect samples. Sample collection and handling requirements are described in Section 7.7.7. 7.7.1.6 Sample Analysis Samples shall be analyzed using the analytical methods identified in the Table 7.11. Samples will be analyzed by: Laboratory Name: Street Address: City, State Zip: Telephone Number: Point of Contact: ELAP Certification Number: Samples will be delivered to the laboratory by: Driven by Contractor Yes No Picked up by Laboratory Courier Yes No Shipped Yes No 7.7.1.7 Data Evaluation and Reporting The QSP shall complete an evaluation of the water quality sample analytical results. Runoff/downgradient results shall be compared with the associated upgradient/unaffected results and any associated run-on results. Should the runoff/downgradient sample show an increased level of the tested analyte relative to the unaffected background sample, which cannot be explained by run-on results, the BMPs, site conditions, and surrounding influences shall be assessed to determine the probable cause for the increase. As determined by the site and data evaluation, appropriate BMPs shall be repaired or modified to mitigate discharges of non-visible pollutant concentrations. Any revisions to the BMPs shall be recorded as an amendment to the SWPPP. Alexan Arcadia 40 December 2023 Table 7.11 Sample Collection, Preservation and Analysis for Monitoring Non-Visible Pollutants Constituent Analytical Method Minimu m Sample Volume Sample Containers Sample Preservation Reporti ng Limit Maximu m Holding Time Notes: Alexan Arcadia 41 December 2023 The General Permit prohibits the storm water discharges that contain hazardous substances equal to or in excess of reportable quantities established in 40 C.F.R. §§ 117.3 and 302.4. The results of any non-stormwater discharge results that indicate the presence of a hazardous substance in excess of established reportable quantities shall be immediately reported to the Regional Water Board and other agencies as required by 40 C.F.R. §§ 117.3 and 302.4. Results of non-visible pollutant monitoring shall be reported in the Annual Report. 7.7.2 Sampling and Analysis Plan for pH and Turbidity in Stormwater Runoff Discharges Sampling and analysis of runoff for pH and turbidity is not required for Risk Level 1 projects. 7.7.3 Sampling and Analysis Plan for pH, Turbidity, and SSC in Receiving Water This project is not subject to Receiving Water Monitoring. 7.7.4 Sampling and Analysis Plan for Non-Stormwater Discharges This project is not subject to the non-stormwater sampling and analysis requirements of the General Permit because it is a Risk Level 1 project. 7.7.5 Sampling and Analysis Plan for Other Pollutants Required by the Regional Water Board The Regional Water Board has not specified monitoring for additional pollutants. 7.7.6 Training of Sampling Personnel Sampling personnel shall be trained to collect, maintain, and ship samples in accordance with the Surface Water Ambient Monitoring program (SWAMP) 2008 Quality Assurance Program Plan (QAPrP). Training records of designated contractor sampling personnel are provided in Appendix K. The stormwater sampler(s) and alternate(s) have received the following stormwater sampling training: Name Training TBD by QSP The stormwater sampler(s) and alternates have the following stormwater sampling experience: Name Experience TBD by QSP 7.7.7 Sample Collection and Handling Alexan Arcadia 42 December 2023 7.7.7.1 Sample Collection Samples shall be collected at the designated sampling locations shown on the Erosion & Sediment Control Plans and listed in the preceding sections. Samples shall be collected, maintained and shipped in accordance with the SWAMP 2008 Quality Assurance Program Plan (QAPrP). Grab samples shall be collected and preserved in accordance with the methods identified in preceding sections. To maintain sample integrity and prevent cross-contamination, sample collection personnel shall follow the protocols below. · Collect samples (for laboratory analysis) only in analytical laboratory-provided sample containers; · Wear clean, powder-free nitrile gloves when collecting samples; · Change gloves whenever something not known to be clean has been touched; · Change gloves between sites; · Decontaminate all equipment (e.g., bucket, tubing) prior to sample collection using a trisodium phosphate water wash, distilled water rinse, and final rinse with distilled water. (Dispose of wash and rinse water appropriately [i.e., do not discharge to storm drain or receiving water]). Do not decontaminate laboratory provided sample containers; · Do not smoke during sampling events; · Never sample near a running vehicle; · Do not park vehicles in the immediate sample collection area (even non-running vehicles); · Do not eat or drink during sample collection; and · Do not breathe, sneeze, or cough in the direction of an open sample container. The most important aspect of grab sampling is to collect a sample that represents the entire runoff stream. Typically, samples are collected by dipping the collection container in the runoff flow paths and streams as noted below. i. For small streams and flow paths, simply dip the bottle facing upstream until full. ii. For larger stream that can be safely accessed, collect a sample in the middle of the flow stream by directly dipping the mouth of the bottle. Once again making sure that the opening of the bottle is facing upstream as to avoid any contamination by the sampler. iii. For larger streams that cannot be safely waded, pole-samplers may be needed to safely access the representative flow. iv. Avoid collecting samples from ponded, sluggish or stagnant water. v. Avoid collecting samples directly downstream from a bridge as the samples can be affected by the bridge structure or runoff from the road surface. Note, that depending upon the specific analytical test, some containers may contain preservatives. These containers should never be dipped into the stream but filled indirectly from the collection container. 7.7.7.2 Sample Handling Turbidity and pH measurements must be conducted immediately. Do not store turbidity or pH samples for later measurement. Alexan Arcadia 43 December 2023 Samples for laboratory analysis must be handled as follows. Immediately following sample collection: · Cap sample containers; · Complete sample container labels; · Sealed containers in a re-sealable storage bag; · Place sample containers into an ice-chilled cooler; · Document sample information on the Effluent Sampling Field Log Sheet; and · Complete the CoC. All samples for laboratory analysis must be maintained between 0-6 degrees Celsius during delivery to the laboratory. Samples must be kept on ice, or refrigerated, from sample collection through delivery to the laboratory. Place samples to be shipped inside coolers with ice. Make sure the sample bottles are well packaged to prevent breakage and secure cooler lids with packaging tape. Ship samples that will be laboratory analyzed to the analytical laboratory right away. Hold times are measured from the time the sample is collected to the time the sample is analyzed. The General Permit requires that samples be received by the analytical laboratory within 48 hours of the physical sampling (unless required sooner by the analytical laboratory). Laboratory Name: Address: City, State Zip: Telephone Number: Point of Contact: 7.7.7.3 Sample Documentation Procedures All original data documented on sample bottle identification labels, Effluent Sampling Field Log Sheet, and CoCs shall be recorded using waterproof ink. These shall be considered accountable documents. If an error is made on an accountable document, the individual shall make corrections by lining through the error and entering the correct information. The erroneous information shall not be obliterated. All corrections shall be initialed and dated. Duplicate samples shall be identified consistent with the numbering system for other samples to prevent the laboratory from identifying duplicate samples. Duplicate samples shall be identified in the Effluent Sampling Field Log Sheet. Sample documentation procedures include the following: Sample Bottle Identification Labels: Sampling personnel shall attach an identification label to each sample bottle. Sample identification shall uniquely identify each sample location. Field Log Sheets: Sampling personnel shall complete the Effluent Sampling Field Log Sheet and Receiving Water Sampling Field Log Sheet for each sampling event, as appropriate. Chain of Custody: Sampling personnel shall complete the CoC for each sampling event for which samples are collected for laboratory analysis. The sampler will sign the CoC when the sample(s) is turned over to the testing laboratory or courier. Alexan Arcadia 44 December 2023 7.8 Active Treatment System Monitoring An Active Treatment System (ATS) will be deployed on the site? Yes No This project does not require a project specific Sampling and Analysis Plan for an ATS because deployment of an ATS is not planned. 7.9 Bioassessment Monitoring This project is not subject to bioassessment monitoring because it is not a Risk Level 3 project. 7.10 Watershed Monitoring Option This project is not participating in a watershed monitoring option. 7.11 Quality Assurance and Quality Control An effective Quality Assurance and Quality Control (QA/QC) plan shall be implemented as part of the CSMP to ensure that analytical data can be used with confidence. QA/QC procedures to be initiated include the following: · Field logs; · Clean sampling techniques; · CoCs; · QA/QC Samples; and · Data verification. Each of these procedures is discussed in more detail in the following sections. 7.11.1 Field Logs The purpose of field logs is to record sampling information and field observations during monitoring that may explain any uncharacteristic analytical results. Sampling information to be included in the field log include the date and time of water quality sample collection, sampling personnel, sample container identification numbers, and types of samples that were collected. Field observations should be noted in the field log for any abnormalities at the sampling location (color, odor, BMPs, etc.). Field measurements for pH and turbidity should also be recorded in the field log. A Visual Inspection Field Log, an Effluent Sampling Field Log Sheet, are included in Appendix Q “Example Forms”. 7.11.2 Clean Sampling Techniques Clean sampling techniques involve the use of certified clean containers for sample collection and clean powder-free nitrile gloves during sample collection and handling. As discussed in Section 7.7.7, adoption of a clean sampling approach will minimize the chance of field contamination and questionable data results. 7.11.3 Chain of Custody The sample CoC is an important documentation step that tracks samples from collection through analysis to ensure the validity of the sample. Sample CoC procedures include the following: · Proper labeling of samples; Alexan Arcadia 45 December 2023 · Use of CoC forms for all samples; and · Prompt sample delivery to the analytical laboratory. Analytical laboratories usually provide CoC forms to be filled out for sample containers. An example CoC is included in Appendix Q “Example Forms”. 7.11.4 QA/QC Samples QA/QC samples provide an indication of the accuracy and precision of the sample collection; sample handling; field measurements; and analytical laboratory methods. The following types of QA/QC will be conducted for this project: Field Duplicates at a frequency TBD by QSP (Required for all sampling plans with field measurements or laboratory analysis) Equipment Blanks at a frequency TBD by QSP (Only needed if equipment used to collect samples could add the pollutants to sample) Field Blanks at a frequency TBD by QSP (Only required if sampling method calls for field blanks) Travel Blanks at a frequency TBD by QSP (Required for sampling plans that include VOC laboratory analysis) 7.11.4.1 Field Duplicates Field duplicates provide verification of laboratory or field analysis and sample collection. Duplicate samples shall be collected, handled, and analyzed using the same protocols as primary samples. The sample location where field duplicates are collected shall be randomly selected from the discharge locations. Duplicate samples shall be collected immediately after the primary sample has been collected. Duplicate samples must be collected in the same manner and as close in time as possible to the original sample. Duplicate samples shall not influence any evaluations or conclusion. 7.11.4.2 Equipment Blanks Equipment blanks provide verification that equipment has not introduced a pollutant into the sample. Equipment blanks are typically collected when: · New equipment is used; · Equipment that has been cleaned after use at a contaminated site; · Equipment that is not dedicated for surface water sampling is used; or · Whenever a new lot of filters is used when sampling metals. 7.11.4.3 Field Blanks Field blanks assess potential sample contamination levels that occur during field sampling activities. De-ionized water field blanks are taken to the field, transferred to the appropriate container, and treated the same as the corresponding sample type during the course of a sampling event. 7.11.4.4 Travel Blanks Travel blanks assess the potential for cross-contamination of volatile constituents between sample containers during shipment from the field to the laboratory. De-ionized water blanks are taken along for the trip and held unopened in the same cooler with the VOC samples. Alexan Arcadia 46 December 2023 7.11.5 Data Verification After results are received from the analytical laboratory, the QSP shall verify the data to ensure that it is complete, accurate, and the appropriate QA/QC requirements were met. Data must be verified as soon as the data reports are received. Data verification shall include: · Check the CoC and laboratory reports. Make sure all requested analyses were performed and all samples are accounted for in the reports. · Check laboratory reports to make sure hold times were met and that the reporting levels meet or are lower than the reporting levels agreed to in the contract. · Check data for outlier values and follow up with the laboratory. Occasionally typographical errors, unit reporting errors, or incomplete results are reported and should be easily detected. These errors need to be identified, clarified, and corrected quickly by the laboratory. The QSP should especially note data that is an order of magnitude or more different than similar locations or is inconsistent with previous data from the same location. · Check laboratory QA/QC results. EPA establishes QA/QC checks and acceptable criteria for laboratory analyses. These data are typically reported along with the sample results. The QSP shall evaluate the reported QA/QC data to check for contamination (method, field, and equipment blanks), precision (laboratory matrix spike duplicates), and accuracy (matrix spikes and laboratory control samples). When QA/QC checks are outside acceptable ranges, the laboratory must flag the data, and usually provides an explanation of the potential impact to the sample results. · Check the data set for outlier values and, accordingly, confirm results and re-analyze samples where appropriate. Sample re-analysis should only be undertaken when it appears that some part of the QA/QC resulted in a value out of the accepted range. Sample results may not be discounted unless the analytical laboratory identifies the required QA/QC criteria were not met and confirms this in writing. Field data including inspections and observations must be verified as soon as the field logs are received, typically at the end of the sampling event. Field data verification shall include: · Check field logs to make sure all required measurements were completed and appropriately documented; · Check reported values that appear out of the typical range or inconsistent; Follow-up immediately to identify potential reporting or equipment problems, if appropriate, recalibrate equipment after sampling; · Verify equipment calibrations; · Review observations noted on the field logs; and · Review notations of any errors and actions taken to correct the equipment or recording errors. 7.12 Records Retention All records of stormwater monitoring information and copies of reports (including Annual Reports) must be retained for a period of at least three years from date of submittal or longer if required by the Regional Water Board. Results of visual monitoring, field measurements, and laboratory analyses must be kept in the SWPPP along with CoCs, and other documentation related to the monitoring. Alexan Arcadia 47 December 2023 Records are to be kept onsite while construction is ongoing. Records to be retained include: · The date, place, and time of inspections, sampling, visual observations, and/or measurements, including precipitation; · The individual(s) who performed the inspections, sampling, visual observation, and/or field measurements; · The date and approximate time of field measurements and laboratory analyses; · The individual(s) who performed the laboratory analyses; · A summary of all analytical results, the method detection limits and reporting limits, and the analytical techniques or methods used; · Rain gauge readings from site inspections; · QA/QC records and results; · Calibration records; · Visual observation and sample collection exemption records; · The records of any corrective actions and follow-up activities that resulted from analytical results, visual observations, or inspections; [and] · [NAL Exceedance Reports]. Section 8 References Project Plans and Specifications No. [None available at this time] State Water Resources Control Board (2009). Order 2009-0009-DWQ, NPDES General Permit No. CAS000002: National Pollutant Discharges Elimination System (NPDES) California General Permit for Storm Water Discharge Associated with Construction and Land Disturbing Activities. Available online at: http://www.waterboards.ca.gov/water_issues/programs/stormwater/construction.shtml. State Water Resources Control Board (2010). Order 2010-0014-DWQ, NPDES General Permit No. CAS000002: National Pollutant Discharges Elimination System (NPDES) California General Permit for Storm Water Discharge Associated with Construction and Land Disturbing Activities. Available online at: http://www.waterboards.ca.gov/water_issues/programs/stormwater/construction.shtml. State Water Resources Control Board (2012). Order 2012-0006-DWQ, NPDES General Permit No. CAS000002: National Pollutant Discharges Elimination System (NPDES) California General Permit for Storm Water Discharge Associated with Construction and Land Disturbing Activities. Available online at: http://www.waterboards.ca.gov/water_issues/programs/stormwater/construction.shtml. CASQA (2019). Construction BMP Handbook. Available online at: www.casqa.org Alexan Arcadia 48 December 2023 Appendix A: Construction General Permit Alexan Arcadia 49 December 2023 Appendix B: Site Map 311 feet PROJECTSITE SITE MAP 34 E SANTA CLARA STREET N. S A N T A A N I T A A V E WHEELER AVE E SANTA CLARA ST NOT A PART AL L E Y LOT 1 LOT 2 WM-1 WM-8 WM-5 SE-1 SE-6 SE-1 SE-6 SE-1 TC-1 TC-3 WM-9 SE-7 SE-10 SE-10 SE-6 SE-6 SE-6 SE-6 SE-6 SE-6 SE-5 SE-6 G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G SE-10 SE-10 SE-10 SE-7 SE-7 SE-7 SE-7 SE-7 SE-7SE-7 SE-7 PAD FG 466.20 PAD FG 470.42 PAD FG 476.92 465.75 FG 475.72 FG 466.75 FG 470.42 FG 2. 0 % 4. 1 % 5. 1 % SE-10 V: \ 1 A R C 0 4 0 1 0 0 \ E N G R \ S H E E T S \ C 2 . 1 0 E r o s i o n & S e d i m e n t C o n t r o l P l a n . d w g 8/ 8 / 2 0 2 3 1 : 5 9 P M 57 9 0 F L E E T S T R E E T , S U I T E 1 4 0 CA R L S B A D , C A 9 2 0 0 8 REVISIONS ISSUE DATE PROJECT NUMBER: 20-301 AL E X A N A R C A D I A MI X E D - U S E / M U L T I - F A M I L Y H O U S I N G PR O J E C T 27 2 2 0 T U R N B E R R Y L A N E , SU I T E 1 9 0 VA L E N C I A , C A 9 1 3 5 5 66 1 . 2 1 9 . 6 0 0 0 50% DD 11/07/2022 34 E . S A N T A C L A R A S T . AR C A D I A , C A 9 1 0 0 6 100% DD 12/19/2022 50% CD 02/13/2023 PC SUBMITTAL 04/24/20236 5 PC SUBMITTAL 2 08/07/20237 LEGEND SILT FENCE (TEMPORARY CONSTRUCTION FENCE) FIBER ROLLS GRAVEL BAG BERM STREET SWEEPING AND VACUUMING STORM DRAIN OUTLET PROTECTION STABILIZED CONSTRUCTION ENTRANCE/EXIT ENTRANCE/OUTLET TIRE WASH DEWATERING OPERATIONS MATERIAL DELIVERY AND STORAGE MATERIAL USE SOLID WASTE MANAGEMENT CONCRETE WASTE MANAGEMENT SANITARY SEPTIC WASTE MANAGEMENT SE-1 SE-6 SE-7 TC-1 WM-1 WM-2 TC-3 SE-10 WM-5 WM-8 WM-9 NS-2 C2.10 EROSION AND SEDIMENT CONTROL PLAN SE-5 Demo/Excavation PC 01/09/2023 8/7/23 V: \ 1 A R C 0 4 0 1 0 0 \ E N G R \ S H E E T S \ C 2 . 1 0 E r o s i o n & S e d i m e n t C o n t r o l P l a n . d w g 8/ 8 / 2 0 2 3 1 : 5 9 P M 57 9 0 F L E E T S T R E E T , S U I T E 1 4 0 CA R L S B A D , C A 9 2 0 0 8 REVISIONS ISSUE DATE PROJECT NUMBER: 20-301 AL E X A N A R C A D I A MI X E D - U S E / M U L T I - F A M I L Y H O U S I N G PR O J E C T 27 2 2 0 T U R N B E R R Y L A N E , SU I T E 1 9 0 VA L E N C I A , C A 9 1 3 5 5 66 1 . 2 1 9 . 6 0 0 0 50% DD 11/07/2022 34 E . S A N T A C L A R A S T . AR C A D I A , C A 9 1 0 0 6 100% DD 12/19/2022 50% CD 02/13/2023 PC SUBMITTAL 04/24/20236 5 PC SUBMITTAL 2 08/07/20237 NTS SILT FENCESE-1 NTS STABILIZED CONSTRUCTION ENTRANCE/EXITTC-1 NTS CONCRETE WASTE MANAGEMENTWM-8 NTS STORM DRAIN INLET PROTECTION SE-10 C2.11 EROSION AND SEDIMENT CONTROL DETAILS NTS GRAVEL BAG BERMSE-8 GRAVEL BAG BERM NTS FIBER ROLLSE-5 Demo/Excavation PC 01/09/2023 8/7/23 N. S A N T A A N I T A A V E WHEELER AVE E SANTA CLARA ST MBA1 LCP PANEL EV3 LINE OF SHORING REFER TO SHORING PLANS FOR DETAILS LINE OF SHORING REFER TO SHORING PLANS FOR DETAILS 5. 1 % 470.42 FG 466.75 FG PAD FG 470.42 PAD FG 476.92 PL R/W 5. 0 0 ' PROPOSED 5' SIDEWALK EASEMENT TO THE CITY PROPOSED 5' SIDEWALK EASEMENT TO THE CITY R/W R/W PL PL R/W 2' SIDEWALK EASEMENT TO THE CITY PL R/W R/W PROPOSED ALLEY IMPROVEMENTS PER SEPARATE PLAN & PERMIT PROPOSED DRIVEWAY & SIDEWALK IMPROVEMENTS PER SEPARATE PLAN & PERMIT PROPOSED DRIVEWAY & SIDEWALK IMPROVEMENTS PER SEPARATE PLAN & PERMIT PROPOSED DRIVEWAY & SIDEWALK IMPROVEMENTS PER SEPARATE PLAN & PERMIT LINE OF SHORING REFER TO SHORING PLANS FOR DETAILS 4. 1 % 470.42 FG 469.84 FG 466.75 FG 476.92 FG 465.75 FG 476.92 FG 464.70 FG 464.70 FG 465.75 FG LINE OF SHORING REFER TO SHORING PLANS FOR DETAILS 1' WIDE STREET DEDICATION TO THE CITY4' STREET DEDICATION TO THE CITY 3' WIDE STREET DEDICATION TO THE CITY 2. 0 % 2. 0 % 2. 0 % 1. 0 : 1 1. 0 : 1 V: \ 1 A R C 0 4 0 1 0 0 \ E N G R \ S H E E T S \ C 2 . 0 0 R o u g h G r a d i n g P l a n . d w g 8/ 8 / 2 0 2 3 1 : 5 8 P M 57 9 0 F L E E T S T R E E T , S U I T E 1 4 0 CA R L S B A D , C A 9 2 0 0 8 REVISIONS ISSUE DATE PROJECT NUMBER: 20-301 AL E X A N A R C A D I A MI X E D - U S E / M U L T I - F A M I L Y H O U S I N G PR O J E C T 27 2 2 0 T U R N B E R R Y L A N E , SU I T E 1 9 0 VA L E N C I A , C A 9 1 3 5 5 66 1 . 2 1 9 . 6 0 0 0 50% DD 11/07/2022 34 E . S A N T A C L A R A S T . AR C A D I A , C A 9 1 0 0 6 100% DD 12/19/2022 50% CD 02/13/2023 PC SUBMITTAL 04/24/20236 5 PC SUBMITTAL 2 08/07/20237 C2.00 ROUGH GRADING PLAN 8/7/23 G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G N. S A N T A A N I T A A V E WHEELER AVE E SANTA CLARA ST ALLEY 30 . 0 0 ' 30 . 0 0 ' 50.00'50.00' 100.00' 60 . 0 0 ' 10.00'10.00' 20.00' 10 . 0 0 ' 10 . 0 0 ' 20 . 0 0 ' MBA1 LCP PANEL EV3 FH FH FH DRIVEWAY ENTRANCE P. A . DRIVEWAY ENTRANCE DRIVEWAY ENTRANCE COMMERCIAL UNITS AMENITIES PROPOSED MIXED-USE BUILDING (7-STORIES AND 2 SUBTERRANEAN LEVELS) LOBBY FF=488.92 FF=489.75 FF=491.00 491.00 FS 491.00 FS 491.00 FS491.00 FS FF=496.25 494.82 FS 495.17 FS 495.17 FS 494.33 FS 491.00 FS 491.00 FS 491.00 FS FF=490.83 FF=489.17 FF=491.54 FF=492.00 494.33 FS 494.33 FS 492.87 FS 494.33 FS 492.50 FS 494.33 FS FF=490.16 491.00 FS FF=489.17 4. 3 % 5. 9 % 2. 4 % 1. 0 % 8.7% 1. 5 % 1. 0 % 1. 8 % 1. 8 % 1. 9 % 1. 9 % 3. 1 % 3. 2 % 2.1% 1.3% 7.0% 1.2% 1.5% 1.7% 1.7% 1. 1 % 2. 3 % 7.5% AL L E Y 491.00 FS 16 . 0 0 ' 1 8 . 0 0 ' 8.50 ' 12.00' 24.00' 30.00' 494.83 FS 492.86 FS 493.22 FS 20.00' C3.11 C3.10 495.01 FS 494.33 FS 494.33 FS 491.00 FS 491.45 FS 490.16 FS 492.87 FS 494.04 FS FF=489.08 1.1% RA M P D O W N T O L E V E L P 1 LINE OF BUILDING ABOVE LINE OF P1 LEVEL BELOW (E) CURB & GUTTER PROP. PL EXIST. V-GUTTER EXIST. CURB & GUTTER EXIST. CURB LINE OF BUILDING ABOVE LINE OF LEVEL P2 BELOW LINE OF BUILDING ABOVE LINE OF LEVELS P1 & P2 BELOW LINE OF LEVELS P1 & P2 BELOW 0"CF 0"CF 6"CF 6"CF 0"CF 0"CF 0"CF 0"CF 6"CF 6"CF LINE OF LEVEL P2 BELOW (E) FF 494.45 (E) FF 494.37 NEW PL PL PL R/W R/W VARIABLE SIDEWALK EASEMENT TO CITY OF ARCADIA 5. 0 0 ' SI D E W A L K EA S E M E N T NEW R/W NEW PL 1' DEDICATION TO CITY OF ARCADIA EXIST. R/W NEW R/W 4' DEDICATION TO CITY OF ARCADIA EXIST. R/W NEW R/W 3' DEDICATION TO CITY OF ARCADIA 2' SIDEWALK EASEMENT TO CITY OF ARCADIA 2' SIDEWALK EASEMENT TO CITY OF ARCADIA R/W PROPOSED SIDEWALK & DRIVEWAY IMPROVEMENTS PER PUBLIC WORKS PLANS & PERMIT PROPOSED SIDEWALK & DRIVEWAY IMPROVEMENTS PER PUBLIC WORKS PLANS & PERMIT PROPOSED ALLEY IMPROVEMENTS PER PUBLIC WORKS PLANS & PERMIT PROPOSED SIDEWALK & DRIVEWAY IMPROVEMENTS PER PUBLIC WORKS PLANS & PERMIT PROPOSED ALLEY IMPROVEMENTS PER PUBLIC WORKS PLANS & PERMIT 2' SIDEWALK EASEMENT TO CITY OF ARCADIA V: \ 1 A R C 0 4 0 1 0 0 \ E N G R \ S H E E T S \ C 3 . 0 0 G r a d i n g . d w g 8/ 8 / 2 0 2 3 1 : 5 9 P M 57 9 0 F L E E T S T R E E T , S U I T E 1 4 0 CA R L S B A D , C A 9 2 0 0 8 REVISIONS ISSUE DATE PROJECT NUMBER: 20-301 AL E X A N A R C A D I A MI X E D - U S E / M U L T I - F A M I L Y H O U S I N G PR O J E C T 27 2 2 0 T U R N B E R R Y L A N E , SU I T E 1 9 0 VA L E N C I A , C A 9 1 3 5 5 66 1 . 2 1 9 . 6 0 0 0 50% DD 11/07/2022 34 E . S A N T A C L A R A S T . AR C A D I A , C A 9 1 0 0 6 100% DD 12/19/2022 50% CD 02/13/2023 PC SUBMITTAL 04/24/20236 5 PC SUBMITTAL 2 08/07/20237 C3.00 OVERALL GRADING & DRAINAGE PLAN SEE SHEETS C3.10 AND C3.11 FOR ON-SITE FINE GRADING AND DRAINAGE LEGEND MAJOR CONTOUR GRADE BREAK FLOW LINE SAWCUT LINE CONCRETE GUTTER STORM DRAIN DRY WELL SETTLEMENT CHAMBER STORMWATER EJECTOR AREA DRAIN ATRIUM DRAIN 8/7/23 Alexan Arcadia 50 December 2023 Appendix C: Permit Registration Documents Rainfall Erosivity Factor Alexan Arcadia R factor = 58.05 + 58.05 + 47.81 Overall R factor = 163.91 N. S A N T A A N I T A A V E WHEELER AVE E SANTA CLARA ST ALLEY MBA1 LCP PANEL EV3 FH FH FH LOT 1 LOT 2 PROPOSED MIXED-USE BUILDING (7-STORIES AND 2 SUBTERRANEAN LEVELS) Average Watershed Slope (%) Sheet Flow Length (ft)0.2 0.5 1.0 2.0 3.0 4.0 5.0 6.0 8.0 10.0 12.0 14.0 <3 0.05 0.07 0.09 0.13 0.17 0.20 0.23 0.26 0.32 0.35 0.36 0.38 6 0.05 0.07 0.09 0.13 0.17 0.20 0.23 0.26 0.32 0.37 0.41 0.45 9 0.05 0.07 0.09 0.13 0.17 0.20 0.23 0.26 0.32 0.38 0.45 0.51 12 0.05 0.07 0.09 0.13 0.17 0.20 0.23 0.26 0.32 0.39 0.47 0.55 15 0.05 0.07 0.09 0.13 0.17 0.20 0.23 0.26 0.32 0.40 0.49 0.58 25 0.05 0.07 0.10 0.16 0.21 0.26 0.31 0.36 0.45 0.57 0.71 0.85 50 0.05 0.08 0.13 0.21 0.30 0.38 0.46 0.54 0.70 0.91 1.15 1.40 75 0.05 0.08 0.14 0.25 0.36 0.47 0.58 0.69 0.91 1.20 1.54 1.87 100 0.05 0.09 0.15 0.28 0.41 0.55 0.68 0.82 1.10 1.46 1.88 2.31 150 0.05 0.09 0.17 0.33 0.50 0.68 0.86 1.05 1.43 1.92 2.51 3.09 200 0.06 0.10 0.18 0.37 0.57 0.79 1.02 1.25 1.72 2.34 3.07 3.81 250 0.06 0.10 0.19 0.40 0.64 0.89 1.16 1.43 1.99 2.72 3.60 4.48 300 0.06 0.10 0.20 0.43 0.69 0.98 1.28 1.60 2.24 3.09 4.09 5.11 400 0.06 0.11 0.22 0.48 0.80 1.14 1.51 1.90 2.70 3.75 5.01 6.30 600 0.06 0.12 0.24 0.56 0.96 1.42 1.91 2.43 3.52 4.95 6.67 8.45 800 0.06 0.12 0.26 0.63 1.10 1.65 2.25 2.89 4.24 6.03 8.17 10.40 1000 0.06 0.13 0.27 0.69 1.23 1.86 2.55 3.30 4.91 7.02 9.57 12.23 LS Factors for Construction Sites. Table from Renard et. al., 1997. Alexan Arcadia 51 December 2023 Permit Registration Documents included in this Appendix: Y/N Permit Registration Document Y Notice of Intent Y Risk Assessment N Certification N Post-Construction Water Balance N Copy of Annual Fee Receipt N ATS Design Documents Y Site Map, see Appendix B Alexan Arcadia 51 August 2023 Permit Registration Documents included in this Appendix: Y/N Permit Registration Document Y Notice of Intent Y Risk Assessment N Certification N Post-Construction Water Balance N Copy of Annual Fee Receipt N ATS Design Documents Y Site Map, see Appendix B GEOTECHNICAL INVESTIGATION ALEXAN ARCADIA PROPOSED MULTI-FAMILY RESIDENTIAL DEVELOPMENT 150 NORTH SANTA ANITA AVENUE ARCADIA, CALIFORNIA PREPARED FOR ARCADIA APARTMENTS, LLC CARLSBAD, CALIFORNIA PROJECT NO. W1304-06-01 MARCH 18, 2021 Project No. W1304-06-01 March 18, 2021 Ms. Ashley Swarts Trammell Crow Residential 5790 Fleet Street, Suite 140 Carlsbad, California 92008 Subject: GEOTECHNICAL INVESTIGATION ALEXAN ARCADIA PROPOSED MULTI-FAMILY RESIDENTIAL DEVELOPMENT 150 NORTH SANTA ANITA AVENUE, ARCADIA, CALIFORNIA Dear Ms. Swarts: In accordance with your authorization of our proposal dated January 19, 2021, we have performed a geotechnical investigation for the proposed multi-family residential development located at 150 North Santa Anita Avenue in the City of Arcadia, California. The accompanying report presents the findings of our study, and our conclusions and recommendations pertaining to the geotechnical aspects of proposed design and construction. Based on the results of our investigation, it is our opinion that the site can be developed as proposed, provided the recommendations of this report are followed and implemented during design and construction. If you have any questions regarding this report, or if we may be of further service, please contact the undersigned. Very truly yours, GEOCON WEST, INC. Petrina Zen PE 87489 Jelisa Thomas Adams GE 3092 Susan F. Kirkgard CEG 1754 (Email) Addressee TABLE OF CONTENTS 1. PURPOSE AND SCOPE ................................................................................................................. 1  2. SITE AND PROJECT DESCRIPTION ........................................................................................... 1  3. GEOLOGIC SETTING .................................................................................................................... 2  4. SOIL AND GEOLOGIC CONDITIONS ......................................................................................... 3  4.1 Artificial Fill .......................................................................................................................... 3  4.2 Alluvium ................................................................................................................................ 3  5. GROUNDWATER ........................................................................................................................... 3  6. GEOLOGIC HAZARDS .................................................................................................................. 4  6.1 Surface Fault Rupture ............................................................................................................ 4  6.2 Seismicity ............................................................................................................................... 5  6.3 Seismic Design Criteria ......................................................................................................... 5  6.4 Liquefaction Potential ............................................................................................................ 7  6.5 Slope Stability ........................................................................................................................ 8  6.6 Earthquake-Induced Flooding ................................................................................................ 8  6.7 Tsunamis, Seiches, and Flooding ........................................................................................... 8  6.8 Oil Fields & Methane Potential ............................................................................................. 9  6.9 Subsidence ............................................................................................................................. 9  7. CONCLUSIONS AND RECOMMENDATIONS ......................................................................... 10  7.1 General ................................................................................................................................. 10  7.2 Soil and Excavation Characteristics ..................................................................................... 12  7.3 Minimum Resistivity, pH, and Water-Soluble Sulfate ........................................................ 12  7.4 Grading ................................................................................................................................ 13  7.5 Foundation Design ............................................................................................................... 15  7.6 Foundation Settlement ......................................................................................................... 16  7.7 Miscellaneous Foundations .................................................................................................. 16  7.8 Lateral Design ...................................................................................................................... 17  7.9 Concrete Slabs-on-Grade ..................................................................................................... 17  7.10 Preliminary Pavement Recommendations ........................................................................... 19  7.11 Retaining Wall Design ......................................................................................................... 21  7.12 Dynamic (Seismic) Lateral Forces ....................................................................................... 23  7.13 Retaining Wall Drainage ...................................................................................................... 23  7.14 Elevator Pit Design .............................................................................................................. 24  7.15 Elevator Piston ..................................................................................................................... 24  7.16 Temporary Excavations ....................................................................................................... 25  7.17 Shoring – Soldier Pile Design and Installation .................................................................... 25  7.18 Temporary Tie-Back Anchors ............................................................................................. 31  7.19 Anchor Installation............................................................................................................... 32  7.20 Anchor Testing .................................................................................................................... 32  7.21 Internal Bracing ................................................................................................................... 33  7.22 Stormwater Infiltration ......................................................................................................... 34  7.23 Surface Drainage .................................................................................................................. 35  7.24 Plan Review ......................................................................................................................... 36  LIMITATIONS AND UNIFORMITY OF CONDITIONS LIST OF REFERENCES TABLE OF CONTENTS (Continued) MAPS, TABLES, AND ILLUSTRATIONS Figure 1, Vicinity Map Figure 2A, Site Plan Figure 2B, Cross Section Figure 3, Regional Fault Map Figure 4, Regional Seismicity Map Figures 5 and 6, Retaining Wall Drain Detail Figure 7, Percolation Test Results APPENDIX A FIELD INVESTIGATION Figures A1 through A4, Boring Logs APPENDIX B LABORATORY TESTING Figures B1 through B7, Direct Shear Test Results Figures B8 through B19, Consolidation Test Results Figure B20, Corrosivity Test Results Geocon Project No. W1304-06-01 - 1 - March 18, 2021 GEOTECHNICAL INVESTIGATION 1. PURPOSE AND SCOPE This report presents the results of a geotechnical investigation for the proposed multi-family residential development located at 150 North Santa Anita Avenue in the City of Arcadia, California (see Vicinity Map, Figure 1). The purpose of the investigation was to evaluate subsurface soil and geologic conditions underlying the site and, based on conditions encountered, to provide conclusions and recommendations pertaining to the geotechnical aspects of design and construction. The scope of this investigation included a site reconnaissance, field exploration, laboratory testing, engineering analysis, and the preparation of this report. The site was explored on February 8, 2021 by excavating four 8-inch diameter borings to depths ranging from approximately 30½ to 40½ feet below the existing ground surface using a truck-mounted, hollow-stem auger drilling machine. The approximate locations of the exploratory borings are depicted on the Site Plan (see Figure 2A). A detailed discussion of the field investigation, including boring logs, is presented in Appendix A. Laboratory tests were performed on selected soil samples obtained during the investigation to determine pertinent physical and chemical soil properties. Appendix B presents a summary of the laboratory test results. The recommendations presented herein are based on analysis of the data obtained during the investigation and our experience with similar soil and geologic conditions. References reviewed to prepare this report are provided in the List of References section. If project details vary significantly from those described herein, Geocon should be contacted to determine the necessity for review and possible revision of this report. 2. SITE AND PROJECT DESCRIPTION The subject site is located at 150 North Santa Anita Avenue in the City of Arcadia, California. The site is currently occupied by a multi-story office tower, several single-story structures, a two-story office building and associated asphalt paved parking lots. The site is bounded by East Santa Clara Street to the north, by Wheeler Avenue to the south, by commercial structures and asphalt paved parking to the east, and by North Santa Anita Avenue to the west. The topography at the site and in the general site vicinity slopes gently downward towards the south. Surface water drainage at the site appears to be by sheet flow along the existing ground contours to the city streets. Vegetation consists of some isolated trees and shrubs in isolated planter areas. Geocon Project No. W1304-06-01 - 2 - March 18, 2021 Based on the information provided by the Client, it is our understanding that the office tower and the single-story commercial structure located on the west side of the property will remain in place; the existing improvements on the east side of the property will be demolished. The new construction will consist of a seven-story multi-family residential structure to be constructed over up to two levels of subterranean parking (see Figures 2A and 2B). Based on the plans provided to us and due to the sloping nature of the site, the structure will be underlain by one subterranean level on the south side and by two subterranean levels on the north side extending to depths of approximately 15 and 26 feet, respectively, including foundation depths. Due to preliminary nature of the design at this time, wall and column loads were not available. It is anticipated that column loads for the proposed structure will be up to 900 kips, and wall loads will be up to 10 kips per linear foot. Once the design phase and foundation loading configuration proceeds to a more finalized plan, the recommendations within this report should be reviewed and revised, if necessary. Any changes in the design, location or elevation of any structure, as outlined in this report, should be reviewed by this office. Geocon should be contacted to determine the necessity for review and possible revision of this report. 3. GEOLOGIC SETTING The site is located in the north-central San Gabriel Valley, approximately 1.0 mile south of the southern flank of the San Gabriel Mountains. The San Gabriel Valley is an alluvium-filled valley bounded by the Sierra Madre Fault Zone and San Gabriel Mountains on the north, by the Puente Hills on the south, by the Covina and Indian Hills on the east, and by the Raymond Basin on the west. The alluvial deposits are derived from erosion of the San Gabriel Mountains to the north and subsequent deposition by the San Gabriel River, Santa Anita Wash, and other local drainages. The alluvium is estimated to be approximately 200 feet thick at the base of the mountains, extending to hundreds of feet thick in the central portion of the valley. Regionally, the site is located within the northern portion of the Peninsular Ranges geomorphic province. This geomorphic province is characterized by northwest-trending physiographic and geologic features such as the active Whittier Fault located approximately 9.4 miles to the south. The active Raymond Fault, located approximately 0.6 mile to the northwest of the site, forms the local boundary between the Peninsular Ranges geomorphic province and the Transverse Ranges geomorphic province to the north. Geocon Project No. W1304-06-01 - 3 - March 18, 2021 4. SOIL AND GEOLOGIC CONDITIONS Based on our field investigation and published geologic maps of the area, the site is underlain by artificial fill and Holocene age alluvium comprised of alluvial channel and outwash deposits consisting of varying amounts of silt, sand, and gravel (California Geological Survey [CGS], 2010). Detailed stratigraphic profiles are provided on the boring logs in Appendix A. 4.1 Artificial Fill Artificial fill was encountered in the exploratory borings to a maximum depth of 4 feet below existing ground surface. The artificial fill generally consists of dark brown silty sand. The fill is characterized as slightly moist to moist and medium dense. The fill is likely the result of past grading or construction activities at the site. Deeper fill may exist between excavations and in other portions of the site that were not directly explored. 4.2 Alluvium Holocene age alluvium was encountered beneath the artificial fill and consists primarily of light brown to brown and reddish brown interbedded silty sand, poorly graded sand, and well-graded sand with varying amounts of fine to coarse gravel. The alluvium is characterized as dry to moist and medium dense to very dense. 5. GROUNDWATER Review of the Seismic Hazard Evaluation of the Mount Wilson 7.5-minute Quadrangle (California Division of Mines and Geology [CDMG], 1998) indicates that the historically highest groundwater level in the immediate area is approximately 100 to 150 feet beneath the ground surface. Groundwater information presented in this document is generated from data collected in the early 1900’s to the late 1990s. Based on current groundwater basin management practices, it is unlikely that groundwater levels will ever exceed the historic high levels. Groundwater was not encountered in our borings drilled to a maximum depth of 40½ feet beneath the existing ground surface. Considering the reported historic high groundwater level (CDMG, 1998), the lack of groundwater encountered in our borings, and the depth of the proposed construction, it is unlikely that groundwater will be encountered during construction or adversely impact the proposed development. However, it is not uncommon for groundwater levels to vary seasonally or for groundwater seepage conditions to develop where none previously existed, especially in impermeable fine-grained soils which are heavily irrigated or after seasonal rainfall. In addition, recent requirements for stormwater infiltration could result in shallower seepage conditions in the immediate site vicinity. Proper surface drainage of irrigation and precipitation will be critical for future performance of the project. Recommendations for drainage are provided in the Surface Drainage section of this report (see Section 7.23). Geocon Project No. W1304-06-01 - 4 - March 18, 2021 6. GEOLOGIC HAZARDS 6.1 Surface Fault Rupture The numerous faults in Southern California include Holocene-active, pre-Holocene, and inactive faults. The criteria for these major groups are based on criteria developed by the California Geological Survey (CGS, formerly known as CDMG) for the Alquist-Priolo Earthquake Fault Zone Program (CGS, 2018). By definition, a Holocene-active fault is one that has had surface displacement within Holocene time (about the last 11,700 years). A pre-Holocene fault has demonstrated surface displacement during Quaternary time (approximately the last 1.6 million years) but has had no known Holocene movement. Faults that have not moved in the last 1.6 million years are considered inactive. The site is not within a state-designated Alquist-Priolo Earthquake Fault Zone (CGS, 2021b; CGS, 2017) or a city-designated Fault Hazard Management Zone (City of Arcadia, 2010) for surface fault rupture hazards. No Holocene-active or pre-Holocene faults with the potential for surface fault rupture are known to pass directly beneath the site. Therefore, the potential for surface rupture due to faulting occurring beneath the site during the design life of the proposed development is considered low. However, the site is located in the seismically active Southern California region, and could be subjected to moderate to strong ground shaking in the event of an earthquake on one of the many active Southern California faults. The faults in the vicinity of the site are shown in Figure 3, Regional Fault Map. The closest Holocene-active fault to the site is the Raymond Fault located approximately 0.6 mile to the northwest (CGS, 2017). Other nearby Holocene-active faults are the Sierra Madre Fault Zone, the Duarte Fault, the East Montebello Fault, and the Whittier Fault located approximately 1.8 miles north, 2.2 miles northeast, 6.3 miles southwest, and 9.4 miles south of the site, respectively. (USGS, 2006; Ziony and Jones, 1989). The active San Andreas Fault Zone is located approximately 23 miles northeast of the site (Ziony and Jones, 1989). Several buried thrust faults, commonly referred to as blind thrusts, underlie the Los Angeles Basin and the San Gabriel Valley at depth. These faults are not exposed at the ground surface and are typically identified at depths greater than 3.0 kilometers. The October 1, 1987 Mw 5.9 Whittier Narrows earthquake and the January 17, 1994 Mw 6.7 Northridge earthquake were a result of movement on the Puente Hills Blind Thrust and the Northridge Thrust, respectively. These thrust faults and others in the greater Los Angeles area are not exposed at the surface and do not present a potential surface fault rupture hazard at the site; however, these deep thrust faults are considered active features capable of generating future earthquakes that could result in moderate to significant ground shaking at the site. Geocon Project No. W1304-06-01 - 5 - March 18, 2021 6.2 Seismicity As with all of Southern California, the site has experienced historic earthquakes from various regional faults. The seismicity of the region surrounding the site was formulated based on research of an electronic database of earthquake data. The epicenters of recorded earthquakes with magnitudes equal to or greater than 5.0 in the site vicinity are depicted on Figure 4, Regional Seismicity Map. A partial list of moderate to major magnitude earthquakes that have occurred in the Southern California area within the last 100 years is included in the following table. LIST OF HISTORIC EARTHQUAKES Earthquake (Oldest to Youngest) Date of Earthquake Magnitude Distance to Epicenter (Miles) Direction to Epicenter Near Redlands July 23, 1923 6.3 46 ESE Long Beach March 10, 1933 6.4 36 S Tehachapi July 21, 1952 7.5 81 NW San Fernando February 9, 1971 6.6 28 NW Whittier Narrows October 1, 1987 5.9 6 SW Sierra Madre June 28, 1991 5.8 8 NNE Landers June 28, 1992 7.3 91 E Big Bear June 28, 1992 6.4 69 E Northridge January 17, 1994 6.7 29 W Hector Mine October 16, 1999 7.1 105 ENE Ridgecrest July 5, 2019 7.1 115 NNE The site could be subjected to strong ground shaking in the event of an earthquake. However, this hazard is common in Southern California and the effects of ground shaking can be mitigated if the proposed structures are designed and constructed in conformance with current building codes and engineering practices. 6.3 Seismic Design Criteria The following table summarizes the site-specific design criteria obtained from the 2019 California Building Code (CBC; Based on the 2018 International Building Code [IBC] and ASCE 7-16), Chapter 16 Structural Design, Section 1613 Earthquake Loads. The data was calculated using the online application Seismic Design Maps, provided by OSHPD. The short spectral response uses a period of 0.2 second. We evaluated the Site Class based on the discussion in Section 1613.2.2 of the 2019 CBC and Table 20.3-1 of ASCE 7-16. The values presented on the following page are for the risk-targeted maximum considered earthquake (MCER). Geocon Project No. W1304-06-01 - 6 - March 18, 2021 2019 CBC SEISMIC DESIGN PARAMETERS Parameter Value 2016 CBC Reference Site Class D Section 1613.3.2 MCER Ground Motion Spectral Response Acceleration – Class B (short), SS 1.963g Figure 1613.3.1(1) MCER Ground Motion Spectral Response Acceleration – Class B (1 sec), S1 0.719g Figure 1613.3.1(2) Site Coefficient, FA 1 Table 1613.3.3(1) Site Coefficient, FV 1.7* Table 1613.3.3(2) Site Class Modified MCER Spectral Response Acceleration (short), SMS 1.963g Section 1613.3.3 (Eqn 16-37) Site Class Modified MCER Spectral Response Acceleration – (1 sec), SM1 1.222g* Section 1613.3.3 (Eqn 16-38) 5% Damped Design Spectral Response Acceleration (short), SDS 1.309g Section 1613.3.4 (Eqn 16-39) 5% Damped Design Spectral Response Acceleration (1 sec), SD1 0.815g* Section 1613.3.4 (Eqn 16-40) Note: *Per Section 11.4.8 of ASCE/SEI 7-16, a ground motion hazard analysis shall be performed for projects for Site Class “E” sites with Ss greater than or equal to 1.0g and for Site Class “D” and “E” sites with S1 greater than 0.2g. Section 11.4.8 also provides exceptions which indicates that the ground motion hazard analysis may be waived provided the exceptions are followed. Using the code based values presented in the table above, in lieu of a performing a ground motion hazard analysis, requires the exceptions outlined in ASCE 7-16 Section 11.4.8 be followed. The table below presents the mapped maximum considered geometric mean (MCEG) seismic design parameters for projects located in Seismic Design Categories of D through F in accordance with ASCE 7-16. ASCE 7-16 PEAK GROUND ACCELERATION Parameter Value ASCE 7-16 Reference Mapped MCEG Peak Ground Acceleration, PGA 0.854g Figure 22-7 Site Coefficient, FPGA 1.1 Table 11.8-1 Site Class Modified MCEG Peak Ground Acceleration, PGAM 0.939g Section 11.8.3 (Eqn 11.8-1) Geocon Project No. W1304-06-01 - 7 - March 18, 2021 The Maximum Considered Earthquake Ground Motion (MCE) is the level of ground motion that has a 2 percent chance of exceedance in 50 years, with a statistical return period of 2,475 years. According to the 2019 California Building Code and ASCE 7-16, the MCE is to be utilized for the evaluation of liquefaction, lateral spreading, seismic settlements, and it is our understanding that the intent of the Building code is to maintain “Life Safety” during a MCE event. The Design Earthquake Ground Motion (DE) is the level of ground motion that has a 10 percent chance of exceedance in 50 years, with a statistical return period of 475 years. Deaggregation of the MCE peak ground acceleration was performed using the USGS online Unified Hazard Tool, 2014 Conterminous U.S. Dynamic edition (v4.2.0). The result of the deaggregation analysis indicates that the predominant earthquake contributing to the MCE peak ground acceleration is characterized as a 7.05 magnitude event occurring at a hypocentral distance of 9.09 kilometers from the site. Deaggregation was also performed for the Design Earthquake (DE) peak ground acceleration, and the result of the analysis indicates that the predominant earthquake contributing to the DE peak ground acceleration is characterized as a 6.96 magnitude occurring at a hypocentral distance of 14.07 kilometers from the site. Conformance to the criteria in the above tables for seismic design does not constitute any kind of guarantee or assurance that significant structural damage or ground failure will not occur if a large earthquake occurs. The primary goal of seismic design is to protect life, not to avoid all damage, since such design may be economically prohibitive. 6.4 Liquefaction Potential Liquefaction is a phenomenon in which loose, saturated, relatively cohesionless soil deposits lose shear strength during strong ground motions. Primary factors controlling liquefaction include intensity and duration of ground motion, gradation characteristics of the subsurface soils, in-situ stress conditions, and the depth to groundwater. Liquefaction is typified by a loss of shear strength in the liquefied layers due to rapid increases in pore water pressure generated by earthquake accelerations. The current standard of practice, as outlined in the “Recommended Procedures for Implementation of DMG Special Publication 117, Guidelines for Analyzing and Mitigating Liquefaction in California” and “Special Publication 117A, Guidelines for Evaluating and Mitigating Seismic Hazards in California” requires liquefaction analysis to a depth of 50 feet below the lowest portion of the proposed structure. Liquefaction typically occurs in areas where the soils below the water table are composed of poorly consolidated, fine to medium-grained, primarily sandy soil. In addition to the requisite soil conditions, the ground acceleration and duration of the earthquake must also be of a sufficient level to induce liquefaction. Geocon Project No. W1304-06-01 - 8 - March 18, 2021 The Seismic Hazards Zone Map for the Mount Wilson Quadrangle (CDMG, 1999; CGS, 2017) indicates that the site is not located within a zone of required investigation for liquefaction. In addition, the City of Arcadia General Plan (2010) and the County of Los Angeles Safety Element (Leighton, 1990), indicate that the site is not located within an area designated as having a potential for liquefaction. Groundwater was not encountered in our borings drilled to a maximum depth of 40½ feet beneath the existing ground surface and the historic high groundwater level in the area is reported to be approximately 100 to 150 feet beneath the existing ground surface (CDMG, 1998). Based on these considerations, it is our opinion that the potential for liquefaction and associated ground deformations beneath the site is very low. 6.5 Slope Stability The site is relatively level and the topography in the site vicinity slopes downward toward the south. The City of Arcadia General Plan (2010) and County of Los Angeles Safety Element (Leighton, 1990), indicate that the site is not located in a “hillside area” or an area identified as having a potential for slope stability hazards. Also, the State of California (CDMG, 1999; CGS, 2017) and the City of Arcadia (2010) indicate that the site is not located within a zone of required investigation for earthquake-induced landslides. There are no known landslides near the site, nor is the site in the path of any known or potential landslides. Therefore, the potential for slope stability hazards to adversely impact the site is considered low. 6.6 Earthquake-Induced Flooding Earthquake-induced flooding is inundation caused by failure of dams or other water-retaining structures due to earthquakes. The City of Arcadia (2010) indicates that the site is located within the potential inundation area for Santa Anita Dam. However, this reservoir, as well as others in California, are continually monitored by various governmental agencies (such as the State of California Division of Safety of Dams and the U.S. Army Corps of Engineers) to guard against the threat of dam failure. Current design, construction practices, and ongoing programs of review, modification, or total reconstruction of existing dams are intended to ensure that all dams are capable of withstanding the maximum considered earthquake (MCE) for the site. Therefore, the potential for inundation at the site as a result of an earthquake-induced dam failure is considered low. 6.7 Tsunamis, Seiches, and Flooding The site is not located within a coastal area. Therefore, tsunamis are not considered a significant hazard at the site. Seiches are large waves generated in enclosed bodies of water in response to ground shaking. No major water-retaining structures are located immediately up gradient from the project site. Therefore, flooding from a seismically induced seiche is considered unlikely. Geocon Project No. W1304-06-01 - 9 - March 18, 2021 The site is within a Zone X as defined by the Federal Emergency Management Agency (FEMA, 2021; LACDPW, 2021b). Sites within a Zone X have a minimal potential for flooding (FEMA, 2021). 6.8 Oil Fields & Methane Potential Review of the California Geologic Energy Management Division (CalGEM) Well Finder Website indicates that the site is not located within the limits of an oilfield and oil or gas wells are not located within ½-mile of the site. However, due to the voluntary nature of record reporting by the oil well drilling companies, wells may be improperly located or not shown on the location map. Undocumented wells could be encountered during construction. Any wells encountered will need to be properly abandoned in accordance with the current requirements of the CalGEM As previously indicated, the site is not located within an oilfield. Therefore, the potential for methane or other volatile gases to occur at the site is considered very low. However, should it be determined that a methane study is required for the proposed development it is recommended that a qualified methane consultant be retained to perform the study and provide mitigation measures as necessary. 6.9 Subsidence Subsidence occurs when a large portion of land is displaced vertically, usually due to the withdrawal of groundwater, oil, or natural gas. Soils that are particularly subject to subsidence include those with high silt or clay content. The site is not located within an area of known ground subsidence. No large-scale extraction of groundwater, gas, oil, or geothermal energy is occurring or planned at the site or in the general site vicinity. There appears to be little or no potential for ground subsidence due to withdrawal of fluids or gases at the site. Geocon Project No. W1304-06-01 - 10 - March 18, 2021 7. CONCLUSIONS AND RECOMMENDATIONS 7.1 General 7.1.1 It is our opinion that neither soil nor geologic conditions were encountered during the investigation that would preclude the construction of the proposed development provided the recommendations presented herein are followed and implemented during design and construction. 7.1.2 Up to 4 feet of existing artificial fill was encountered during the site investigation. The existing fill encountered is believed to be the result of past grading and construction activities at the site. Deeper fill may exist in other areas of the site that were not directly explored. Future demolition of the existing structures which occupy the site will likely disturb the upper few feet of soil. It is our opinion that the existing fill, in its present condition, is not suitable for direct support of proposed foundations or slabs. The existing fill and site soils are suitable for re-use as engineered fill provided the recommendations in the Grading section of this report are followed (see Section 7.4). Excavation for the subterranean levels are anticipated to penetrate through the existing artificial fill and expose undisturbed alluvial soils throughout the excavation bottom. 7.1.3 Groundwater was not encountered during site exploration and the current groundwater table is sufficiently deep that it not expected to be encountered during construction. However, local seepage could be encountered during excavation of the subterranean level, especially if conducted during the rainy season. 7.1.4 Based on these considerations, the proposed structure may be supported on conventional foundation system deriving support in the competent alluvium found at and below a depth of 12 feet. Foundations should be deepened as necessary to penetrate through soft or unsuitable alluvium at the direction of the Geotechnical Engineer. All foundation excavations must be observed and approved by the Geotechnical Engineer (a representative of Geocon), prior to placing steel or concrete. Recommendations for the design of a conventional foundation system are provided in Section 7.5. 7.1.5 Excavations up to 26 feet in vertical height are anticipated for construction of the subterranean levels, including foundation depths. Due to the depth of the excavation and the proximity to the property lines, city streets and adjacent offsite structures, excavation of the proposed subterranean level will likely require sloping and shoring measures in order to provide a stable excavation. Where shoring is required it is recommended that a soldier pile shoring system be utilized. In addition, where the proposed excavation will be deeper than and adjacent to an offsite structure, the proposed shoring should be designed to resist the surcharge imposed by the adjacent offsite structure. Recommendations for shoring are provided in Section 7.17 of this report. Geocon Project No. W1304-06-01 - 11 - March 18, 2021 7.1.6 Due to the granular nature of the soils, moderate to excessive caving is anticipated during excavation activities. The contractor should be aware that casing may be required during shoring pile installation and formwork may be required to prevent caving of shallow spread foundation excavations. 7.1.7 Due to the nature of the proposed design and intent for a subterranean level, waterproofing of subterranean walls and slabs is suggested. Particular care should be taken in the design and installation of waterproofing to avoid moisture problems, or actual water seepage into the structure through any normal shrinkage cracks which may develop in the concrete walls, floor slab, foundations and/or construction joints. The design and inspection of the waterproofing is not the responsibility of the geotechnical engineer. A waterproofing consultant should be retained in order to recommend a product or method, which would provide protection to subterranean walls, floor slabs and foundations. 7.1.8 Foundations for small outlying structures, such as block walls up to 6 feet in height, planter walls or trash enclosures, which will not be tied to the proposed structure, may be supported on conventional foundations deriving support on a minimum of 12 inches of newly placed engineered fill, which extends laterally at least 12 inches beyond the foundation area. Where excavation and compaction cannot be performed or is undesirable, foundations may derive support directly in the competent undisturbed alluvial soils found at or below a depth of 24 inches, and should be deepened as necessary to maintain a minimum 12 inch embedment into the recommended bearing materials. If the soils exposed in the excavation bottom are soft or loose, compaction of the soils will be required prior to placing steel or concrete. Compaction of the foundation excavation bottom is typically accomplished with a compaction wheel or mechanical whacker and must be observed and approved by a Geocon representative. 7.1.9 Where new paving is to be placed, it is recommended that all existing fill and soft alluvial soils be excavated and properly compacted for paving support. The client should be aware that excavation and compaction of all existing fill and soft alluvial soils in the area of new paving is not required; however, paving constructed over existing uncertified fill or unsuitable alluvial soil may experience increased settlement and/or cracking, and may therefore have a shorter design life and increased maintenance costs. As a minimum, the upper 12 inches of subgrade soil should be scarified and properly compacted for paving support. Paving recommendations are provided in Preliminary Pavement Recommendations section of this report (see Section 7.10). 7.1.10 Based on the results of percolation testing performed at the site, a stormwater infiltration system is considered feasible for this project. Results of percolation testing are provided in the Stormwater Infiltration section of this report (see Section 7.22). Geocon Project No. W1304-06-01 - 12 - March 18, 2021 7.1.11 Once the design and foundation loading configuration for the proposed structure proceeds to a more finalized plan, the recommendations within this report should be reviewed and revised, if necessary. Based on the final foundation loading configurations, the potential for settlement should be re-evaluated by this office. 7.1.12 Any changes in the design, location or elevation, as outlined in this report, should be reviewed by this office. Geocon should be contacted to determine the necessity for review and possible revision of this report. 7.2 Soil and Excavation Characteristics 7.2.1 The in-situ soils can be excavated with moderate effort using conventional excavation equipment. Due to the granular nature of the soils, moderate to excessive caving should be anticipated in vertical excavations. The contractor should be aware that casing may be required during shoring pile installation and formwork may be required to prevent caving of shallow spread foundation excavations. 7.2.2 It is the responsibility of the contractor to ensure that all excavations and trenches are properly shored and maintained in accordance with applicable OSHA rules and regulations to maintain safety and maintain the stability of existing adjacent improvements. 7.2.3 All onsite excavations must be conducted in such a manner that potential surcharges from existing structures, construction equipment, and vehicle loads are resisted. The surcharge area may be defined by a 1:1 projection down and away from the bottom of an existing foundation or vehicle load. Penetrations below this 1:1 projection will require special excavation measures such as sloping or shoring. Excavation recommendations are provided in the Temporary Excavations section of this report (see Section 7.16). 7.2.4 Based on depth of the proposed subterranean levels, the proposed structure would not be prone to the effects of expansive soils. The soils encountered at the site are primarily granular in nature and are considered to be “non-expansive”. The recommendations presented in this report assume that near surface foundations and slabs will derive support in these materials with a “low” expansion potential (EI <= 50). 7.3 Minimum Resistivity, pH, and Water-Soluble Sulfate 7.3.1 Potential of Hydrogen (pH) and resistivity testing as well as chloride content testing were performed on representative samples of soil to generally evaluate the corrosion potential to surface utilities. The tests were performed in accordance with California Test Method Nos. 643 and 422 and indicate that the soils are considered “mildly corrosive” with respect to corrosion of buried ferrous metals on site. The results are presented in Appendix B (Figure B20) and should be considered for design of underground structures. Geocon Project No. W1304-06-01 - 13 - March 18, 2021 7.3.2 Laboratory tests were performed on representative samples of the site materials to measure the percentage of water-soluble sulfate content. Results from the laboratory water-soluble sulfate tests are presented in Appendix B (Figure B20) and indicate that the on-site materials possess a sulfate exposure class of “S0” to concrete structures as defined by 2019 CBC Section 1904 and ACI 318-14 Table 19.3.1.1. 7.3.3 Geocon West, Inc. does not practice in the field of corrosion engineering and mitigation. If corrosion sensitive improvements are planned, it is recommended that a corrosion engineer be retained to evaluate corrosion test results and incorporate the necessary precautions to avoid premature corrosion of buried metal pipes and concrete structures in direct contact with the soils. 7.4 Grading 7.4.1 Grading is anticipated to include excavation of site soils for the subterranean level, foundations, and utility trenches, as well as placement of backfill for walls, ramps, and trenches. 7.4.2 Earthwork should be observed, and compacted fill tested by representatives of Geocon West, Inc. The existing fill and alluvial soil encountered during exploration is suitable for re-use as engineered fill, provided any encountered oversize material (greater than 6 inches) and any encountered deleterious debris are removed. 7.4.3 A preconstruction conference should be held at the site prior to the beginning of grading operations with the owner, contractor, civil engineer, geotechnical engineer, and building official in attendance. Special soil handling requirements can be discussed at that time. 7.4.4 Grading should commence with the removal of all existing vegetation and existing improvements from the area to be graded. Deleterious debris such as wood and root structures should be exported from the site and should not be mixed with the fill soils. Asphalt and concrete should not be mixed with the fill soils unless approved by the Geotechnical Engineer. All existing underground improvements planned for removal should be completely excavated and the resulting depressions properly backfilled in accordance with the procedures described herein. Once a clean excavation bottom has been established it must be observed and approved in writing by the Geotechnical Engineer (a representative of Geocon West, Inc.). 7.4.5 The foundation system for the proposed structure may derive support in the competent undisturbed alluvial soils found at and below a depth of 12 feet. 7.4.6 All excavations must be observed and approved in writing by the Geotechnical Engineer (a representative of Geocon) prior to placing any fill or foundation construction. Geocon Project No. W1304-06-01 - 14 - March 18, 2021 7.4.7 All fill and backfill soils should be placed in horizontal loose layers approximately 6 to 8 inches thick, moisture conditioned to optimum moisture content, and properly compacted to a minimum of 90 percent of the maximum dry density in accordance with ASTM D 1557 (latest edition). 7.4.8. Where new paving is to be placed, it is recommended that all existing fill and soft alluvium be excavated and properly compacted for paving support. As a minimum, the upper 12 inches of soil should be scarified, moisture conditioned to optimum moisture content, and compacted to at least 95 percent relative compaction, as determined by ASTM D 1557 (latest edition). Paving recommendations are provided in Preliminary Pavement Recommendations section of this report (see Section 7.10). 7.4.9 Foundations for small outlying structures, such as block walls less than 6 feet high, planter walls or trash enclosures, which will not be tied to the proposed building, may be supported on conventional foundations deriving support on a minimum of 12 inches of newly placed engineered fill which extends laterally at least 12 inches beyond the foundation area. Where excavation and proper compaction cannot be performed or is undesirable, foundations may derive support directly in the undisturbed alluvial soils found at or below a depth of 24 inches, and should be deepened as necessary to maintain a minimum 12 inch embedment into the recommended bearing materials. If the soils exposed in the excavation bottom are soft or loose, compaction of the soils will be required prior to placing steel or concrete. Compaction of the foundation excavation bottom is typically accomplished with a compaction wheel or mechanical whacker and must be observed and approved by a Geocon representative. 7.4.10 Although not anticipated for this project, all imported fill shall be observed, tested, and approved by Geocon West, Inc. prior to bringing soil to the site. Rocks larger than 6 inches in diameter shall not be used in the fill. If necessary, import soils used as structural fill should have an expansion index less than 20 and corrosivity properties that are equally or less detrimental to that of the existing onsite soils (see Figure B20). 7.4.11 Utility trenches should be properly backfilled in accordance with the requirements of the Green Book (latest edition). The pipe should be bedded with clean sands (Sand Equivalent greater than 30) to a depth of at least 1 foot over the pipe, and the bedding material must be inspected and approved in writing by the Geotechnical Engineer (a representative of Geocon). The use of gravel is not acceptable unless used in conjunction with filter fabric to prevent the gravel from having direct contact with soil. The remainder of the trench backfill may be derived from onsite soil or approved import soil, compacted as necessary, until the required compaction is obtained. The use of minimum 2-sack slurry as backfill is also acceptable. Prior to placing any bedding materials or pipes, the excavation bottom must be observed and approved in writing by the Geotechnical Engineer (a representative of Geocon). Geocon Project No. W1304-06-01 - 15 - March 18, 2021 7.4.12 All trench and foundation excavation bottoms must be observed and approved in writing by the Geotechnical Engineer (a representative of Geocon), prior to placing bedding materials, fill, steel, gravel, or concrete. 7.5 Foundation Design 7.5.1 The proposed structure may be supported on a conventional foundation system deriving support in the competent alluvium found at and below a depth of 12 feet. Foundations should be deepened as necessary to penetrate through soft or unsuitable alluvium at the direction of the Geotechnical Engineer. All foundation excavations must be observed and approved by the Geotechnical Engineer (a representative of Geocon), prior to placing steel or concrete. 7.5.2 Continuous footings may be designed for an allowable bearing capacity of 2,500 pounds per square foot (psf), and should be a minimum of 12 inches in width, 18 inches in depth below the lowest adjacent grade, and 12 inches into the recommended bearing material. 7.5.3 Isolated spread foundations may be designed for an allowable bearing capacity of 3,000 psf, and should be a minimum of 24 inches in width, 18 inches in depth below the lowest adjacent grade, and 12 inches into the recommended bearing material. 7.5.4 The allowable soil bearing pressure above may be increased by 250 psf and 500 psf for each additional foot of foundation width and depth, respectively, up to a maximum allowable soil bearing pressure of 4,000 psf. 7.5.5 The allowable bearing pressures may be increased by one-third for transient loads due to wind or seismic forces. 7.5.6 If depth increases are utilized for the perimeter foundations, this office should be provided a copy of the final construction plans so that the excavation recommendations presented herein could be properly reviewed and revised if necessary. 7.5.7 Continuous footings should be reinforced with four No. 4 steel reinforcing bars, two placed near the top of the footing and two near the bottom. Reinforcement for spread footings should be designed by the project structural engineer. 7.5.8 The above foundation dimensions and minimum reinforcement recommendations are based on soil conditions and building code requirements only, and are not intended to be used in lieu of those required for structural purposes. 7.5.9 No special subgrade presaturation is required prior to placement of concrete. However, the slab and foundation subgrade should be sprinkled as necessary; to maintain a moist condition as would be expected in any concrete placement. Geocon Project No. W1304-06-01 - 16 - March 18, 2021 7.5.10 Foundation excavations should be observed and approved in writing by the Geotechnical Engineer (a representative of Geocon West, Inc.), prior to the placement of reinforcing steel and concrete to verify that the excavations and exposed soil conditions are consistent with those anticipated. If unanticipated soil conditions are encountered, foundation modifications may be required. 7.5.11 This office should be provided a copy of the final construction plans so that the excavation recommendations presented herein could be properly reviewed and revised if necessary. 7.6 Foundation Settlement 7.6.1 The maximum expected static settlement for a structure supported on a conventional foundation system deriving support in the recommended bearing materials and designed with a maximum bearing pressure of 4,000 psf is estimated to be less than 1¼ inches and occur below the heaviest loaded structural element. Settlement of the foundation system is expected to occur on initial application of loading. Differential settlement is not expected to exceed ¾ inch over a distance of 20 feet. 7.6.2 Once the design and foundation loading configuration for the proposed structure proceeds to a more finalized plan, the estimated settlements presented in this report should be reviewed and revised, if necessary. If the final foundation loading configurations are greater than the assumed loading conditions, the potential for settlement should be reevaluated by this office. 7.7 Miscellaneous Foundations 7.7.1 Foundations for small outlying structures, such as block walls up to 6 feet in height, planter walls or trash enclosures which will not be tied to the proposed structure may be supported on conventional foundations bearing on a minimum of 12 inches of newly placed engineered fill which extends laterally at least 12 inches beyond the foundation area. Where excavation and compaction cannot be performed or is undesirable, such as adjacent to property lines, foundations may derive support in the undisturbed alluvial soils found at or below a depth of 24 inches, and should be deepened as necessary to maintain a minimum 12 inch embedment into the recommended bearing materials. 7.7.2 If the soils exposed in the excavation bottom are soft, compaction of the soft soils will be required prior to placing steel or concrete. Compaction of the foundation excavation bottom is typically accomplished with a compaction wheel or mechanical whacker and must be observed and approved by a Geocon representative. Miscellaneous foundations may be designed for a bearing value of 1,500 psf, and should be a minimum of 12 inches in width, 18 inches in depth below the lowest adjacent grade and 12 inches into the recommended bearing material. The allowable bearing pressure may be increased by up to one-third for transient loads due to wind or seismic forces. Geocon Project No. W1304-06-01 - 17 - March 18, 2021 7.7.3 Foundation excavations should be observed and approved in writing by the Geotechnical Engineer (a representative of Geocon West, Inc.), prior to the placement of reinforcing steel and concrete to verify that the excavations and exposed soil conditions are consistent with those anticipated. 7.8 Lateral Design 7.8.1 Resistance to lateral loading may be provided by friction acting at the base of foundations, slabs and by passive earth pressure. An allowable coefficient of friction of 0.4 may be used with the dead load forces in the competent alluvial soils and properly compacted engineered fill. 7.8.2 Passive earth pressure for the sides of foundations and slabs poured against properly compacted engineered fill or competent alluvial soils may be computed as an equivalent fluid having a density of 330 pcf with a maximum earth pressure of 3,300 psf. When combining passive and friction for lateral resistance, the passive component should be reduced by one-third. 7.9 Concrete Slabs-on-Grade 7.9.1 Exterior concrete slabs-on-grade subject to vehicle loading should be designed in accordance with the recommendations in the Preliminary Pavement Recommendations section of this report (Section 7.10). 7.9.2 Unless specifically evaluated and designed by a qualified structural engineer, the slab-on-grade and ramp for the subterranean parking garage slab-on-grade should be a minimum of 5 inches of concrete reinforced with No. 3 steel reinforcing bars placed 18 inches on center in both horizontal directions and positioned vertically near the slab midpoint. The concrete slab-on-grade and ramp may derive support directly on the undisturbed alluvial soils at the excavation bottom as well as compacted soils, if necessary. Any disturbed soils should be properly compacted for slab support. Soil placed and compacted for ramp and slab support should be moisture conditioned to optimum moisture content and properly compacted to at least 95 percent relative compaction, as determined by ASTM Test Method D 1557 (latest edition) for ramp support. Geocon Project No. W1304-06-01 - 18 - March 18, 2021 7.9.3 Slabs-on-grade at the ground surface that may receive moisture-sensitive floor coverings or may be used to store moisture-sensitive materials should be underlain by a vapor retarder placed directly beneath the slab. The vapor retarder and acceptable permeance should be specified by the project architect or developer based on the type of floor covering that will be installed. The vapor retarder design should be consistent with the guidelines presented in Section 9.3 of the American Concrete Institute’s (ACI) Guide for Concrete Slabs that Receive Moisture-Sensitive Flooring Materials (ACI 302.2R-06) and should be installed in general conformance with ASTM E 1643 (latest edition) and the manufacturer’s recommendations. A minimum thickness of 15 mils extruded polyolefin plastic is recommended; vapor retarders which contain recycled content or woven materials are not recommended. The vapor retarder should have a permeance of less than 0.01 perms demonstrated by testing before and after mandatory conditioning. The vapor retarder should be installed in direct contact with the concrete slab with proper perimeter seal. If the California Green Building Code requirements apply to this project, the vapor retarder should be underlain by 4 inches of clean aggregate. It is important that the vapor retarder be puncture resistant since it will be in direct contact with angular gravel. As an alternative to the clean aggregate suggested in the Green Building Code, it is our opinion that the concrete slab-on-grade may be underlain by a vapor retarder over 4 inches of clean sand (sand equivalent greater than 30), since the sand will serve a capillary break and will minimize the potential for punctures and damage to the vapor barrier. 7.9.4 Due to the nature of the proposed design and intent for a subterranean level, waterproofing of subterranean walls and slabs is suggested. Particular care should be taken in the design and installation of waterproofing to avoid moisture problems, or actual water seepage into the structure through any normal shrinkage cracks which may develop in the concrete walls, floor slab, foundations and/or construction joints. The design and inspection of the waterproofing is not the responsibility of the geotechnical engineer. A waterproofing consultant should be retained in order to recommend a product or method, which would provide protection to subterranean walls, floor slabs and foundations. 7.9.5 For seismic design purposes, a coefficient of friction of 0.4 may be utilized between concrete slabs and subgrade soils without a moisture barrier, and 0.15 for slabs underlain by a moisture barrier. Geocon Project No. W1304-06-01 - 19 - March 18, 2021 7.9.6 Exterior slabs for walkways or flatwork, not subject to traffic loads, should be at least 4 inches thick and reinforced with No. 3 steel reinforcing bars placed 18 inches on center in both horizontal directions, positioned near the slab midpoint. Prior to construction of slabs, the upper 12 inches of subgrade should be moistened to optimum moisture content and properly compacted to at least 95 percent relative compaction, as determined by ASTM Test Method D 1557 (latest edition). Crack control joints should be spaced at intervals not greater than 10 feet and should be constructed using saw-cuts or other methods as soon as practical following concrete placement. Crack control joints should extend a minimum depth of one- fourth the slab thickness. The project structural engineer should design construction joints as necessary. 7.9.7 The recommendations of this report are intended to reduce the potential for cracking of slabs due to settlement. However, even with the incorporation of the recommendations presented herein, foundations, stucco walls, and slabs-on-grade may exhibit some cracking due to minor soil movement and/or concrete shrinkage. The occurrence of concrete shrinkage cracks is independent of the supporting soil characteristics. Their occurrence may be reduced and/or controlled by limiting the slump of the concrete, proper concrete placement and curing, and by the placement of crack control joints at periodic intervals, in particular, where re-entrant slab corners occur. 7.10 Preliminary Pavement Recommendations 7.10.1 Where new paving is to be placed, it is recommended that all existing fill and soft or unsuitable alluvial materials be excavated and properly recompacted for paving support. The client should be aware that excavation and compaction of all existing artificial fill and soft alluvium in the area of new paving is not required; however, paving constructed over existing unsuitable material may experience increased settlement and/or cracking, and may therefore have a shorter design life and increased maintenance costs. As a minimum, the upper 12 inches of paving subgrade should be scarified, moisture conditioned to optimum moisture content, and properly compacted to at least 95 percent relative compaction, as determined by ASTM Test Method D 1557 (latest edition). 7.10.2 The following pavement sections are based on an assumed R-Value of 35. Once site grading activities are complete an R-Value should be obtained by laboratory testing to confirm the properties of the soils serving as paving subgrade, prior to placing pavement. Geocon Project No. W1304-06-01 - 20 - March 18, 2021 7.10.3 The Traffic Indices listed below are estimates. Geocon does not practice in the field of traffic engineering. The actual Traffic Index for each area should be determined by the project civil engineer. If pavement sections for Traffic Indices other than those listed below are required, Geocon should be contacted to provide additional recommendations. Pavement thicknesses were determined following procedures outlined in the California Highway Design Manual (Caltrans). It is anticipated that the majority of traffic will consist of automobile and large truck traffic. PRELIMINARY PAVEMENT DESIGN SECTIONS Location Estimated Traffic Index (TI) Asphalt Concrete (inches) Class 2 Aggregate Base (inches) Automobile Parking And Driveways 4.0 3.0 4.0 Trash Truck & Fire Lanes 7.0 4.0 9.0 7.10.4 Asphalt concrete should conform to Section 203-6 of the “Standard Specifications for Public Works Construction” (Green Book). Class 2 aggregate base materials should conform to Section 26-1.02A of the “Standard Specifications of the State of California, Department of Transportation” (Caltrans). The use of Crushed Miscellaneous Base in lieu of Class 2 aggregate base is acceptable. Crushed Miscellaneous Base should conform to Section 200-2.4 of the “Standard Specifications for Public Works Construction” (Green Book). 7.10.5 Unless specifically designed and evaluated by the project structural engineer, where exterior concrete paving will be utilized for support of vehicles, it is recommended that the concrete be a minimum of 6 inches thick and reinforced with No. 3 steel reinforcing bars placed 18 inches on center in both horizontal directions. Concrete paving supporting vehicular traffic should be underlain by a minimum of 4 inches of aggregate base and a properly compacted subgrade. The subgrade and base material should be compacted to 95 percent relative compaction as determined by ASTM Test Method D 1557 (latest edition). 7.10.6 The performance of pavements is highly dependent upon providing positive surface drainage away from the edge of pavements. Ponding of water on or adjacent to the pavement will likely result in saturation of the subgrade materials and subsequent cracking, subsidence and pavement distress. If planters are planned adjacent to paving, it is recommended that the perimeter curb be extended at least 12 inches below the bottom of the aggregate base to minimize the introduction of water beneath the paving. Geocon Project No. W1304-06-01 - 21 - March 18, 2021 7.11 Retaining Wall Design 7.11.1 The recommendations presented below are generally applicable to the design of rigid concrete or masonry retaining walls having a maximum height of 24 feet. In the event that walls significantly higher than 24 feet are planned, Geocon should be contacted for additional recommendations. 7.11.2 Retaining wall foundations may be designed in accordance with the recommendations provided in the Foundation Design section of this report (see Section 7.5). 7.11.3 Retaining walls with a level backfill surface that are not restrained at the top should be designed utilizing a triangular distribution of pressure (active pressure). Restrained walls are those that are not allowed to rotate more than 0.001H (where H equals the height of the retaining portion of the wall in feet) at the top of the wall. Where walls are restrained from movement at the top, walls may be designed utilizing a triangular distribution of pressure (at-rest pressure). The table below presents recommended pressures to be used in retaining wall design, assuming that proper drainage will be maintained. RETAINING WALL WITH LEVEL BACKFILL SURFACE HEIGHT OF RETAINING WALL (Feet) ACTIVE PRESSURE EQUIVALENT FLUID PRESSURE (Pounds Per Cubic Foot) AT-REST PRESSURE EQUIVALENT FLUID PRESSURE (Pounds Per Cubic Foot) Up to 13 34 48 14-24 46 50 7.11.4 The wall pressures provided above assume that the proposed retaining walls will support relatively undisturbed alluvial soils. If sloping techniques are to be utilized for construction of proposed walls, which would result in a wedge of engineered fill behind the retaining walls, revised earth pressures may be required. This should be evaluated once the use of sloping measures is established and once the geotechnical characteristics of the engineered backfill soils can be further evaluated. 7.11.5 The wall pressures provided above assume that the retaining wall will be properly drained preventing the buildup of hydrostatic pressure. If retaining wall drainage is not implemented, the equivalent fluid pressure to be used in design of undrained walls is 90 pcf. The value includes hydrostatic pressures plus buoyant lateral earth pressures. 7.11.6 Additional active pressure should be added for a surcharge condition due to sloping ground, vehicular traffic or adjacent structures and should be designed for each condition as the project progresses. Geocon Project No. W1304-06-01 - 22 - March 18, 2021 7.11.7 It is recommended that line-load surcharges from adjacent wall footings, use horizontal pressures generated from NAV-FAC DM 7.2. The governing equations are: ܨ݋ݎ ݔ ܪൗ ൑ 0.4 ߪுሺݖሻ ൌ 0.20 ൈ ቀݖ ܪቁ ൤0.16 ൅ ቀݖ ܪቁଶ൨ ଶ ൈ ܳ௅ ܪ and ܨ݋ݎ ݔ ܪൗ ൐ 0.4 ߪுሺݖሻ ൌ 1.28 ൈ ቀݔܪቁଶ ൈ ቀݖܪቁ ൤ቀݔܪቁଶ ൅ ቀݖܪቁଶ൨ ଶ ൈ ܳ௅ ܪ where x is the distance from the face of the excavation or wall to the vertical line-load, H is the distance from the bottom of the footing to the bottom of excavation or wall, z is the depth at which the horizontal pressure is desired, QL is the vertical line-load and σHሺzሻ is the horizontal pressure at depth z. 7.11.8 It is recommended that vertical point-loads, from construction equipment outriggers or adjacent building columns use horizontal pressures generated from NAV-FAC DM 7.2. The governing equations are: ܨ݋ݎ ݔ ܪൗ ൑ 0.4 ߪுሺݖሻ ൌ 0.28 ൈ ቀ ݖܪቁଶ ൤0.16 ൅ ቀݖ ܪቁଶ൨ଷ ൈ ܳ௉ ܪଶ and ܨ݋ݎ ݔ ܪൗ ൐ 0.4 ߪுሺݖሻ ൌ 1.77 ൈ ቀݔ ܪቁଶ ൈ ቀݖ ܪቁଶ ൤ቀݔ ܪቁଶ ൅ ቀݖ ܪቁଶ൨ ଷ ൈ ܳ௉ ܪଶ then ߪᇱு ሺݖሻ ൌ ߪுሺݖሻܿ݋ݏଶ ሺ1.1ߠሻ where x is the distance from the face of the excavation/wall to the vertical point-load, H is distance from the outrigger/bottom of column footing to the bottom of excavation, z is the depth at which the horizontal pressure is desired, Qp is the vertical point-load, σHሺzሻ is the horizontal pressure at depth z, ϴ is the angle between a line perpendicular to the excavation/wall and a line from the point-load to location on the excavation/wall where the surcharge is being evaluated, and σHሺzሻ is the horizontal pressure at depth z. Geocon Project No. W1304-06-01 - 23 - March 18, 2021 7.11.9 In addition to the recommended earth pressure, the upper 10 feet of the retaining wall adjacent to the street or driveway areas should be designed to resist a uniform lateral pressure of 100 psf, acting as a result of an assumed 300 psf surcharge behind the wall due to normal street traffic. If the traffic is kept back at least 10 feet from the wall, the traffic surcharge may be neglected. 7.11.10 Seismic lateral forces should be incorporated into the design as necessary, and recommendations for seismic lateral forces are presented below. 7.12 Dynamic (Seismic) Lateral Forces 7.12.1 The structural engineer should determine the seismic design category for the project in accordance with Section 1613 of the CBC. If the project possesses a seismic design category of D, E, or F, proposed retaining walls in excess of 6 feet in height should be designed with seismic lateral pressure (Section 1803.5.12 of the 2019 CBC). 7.12.2 A seismic load of 10 pcf should be used for design of walls that support more than 6 feet of backfill in accordance with Section 1803.5.12 of the 2019 CBC. The seismic load is applied as an equivalent fluid pressure along the height of the wall and the calculated loads result in a maximum load exerted at the base of the wall and zero at the top of the wall. This seismic load should be applied in addition to the active earth pressure. The earth pressure is based on half of two-thirds of PGAM calculated from ASCE 7-16 Section 11.8.3. 7.13 Retaining Wall Drainage 7.13.1 Unless designed for hydrostatic pressures, retaining walls should be provided with a drainage system. At the base of the drain system, a subdrain covered with a minimum of 12 inches of gravel should be installed, and a compacted fill blanket or other seal placed at the surface (see Figure 5). The clean bottom and subdrain pipe, behind a retaining wall, should be observed by the Geotechnical Engineer (a representative of Geocon), prior to placement of gravel or compacting backfill. 7.13.2 As an alternative, a plastic drainage composite such as Miradrain or equivalent may be installed in continuous, 4-foot wide columns along the entire back face of the wall, at 8 feet on center. The top of these drainage composite columns should terminate approximately 18 inches below the ground surface, where either hardscape or a minimum of 18 inches of relatively cohesive material should be placed as a cap (see Figure 6). These vertical columns of drainage material would then be connected at the bottom of the wall to a collection panel or a 1-cubic-foot rock pocket drained by a 4-inch subdrain pipe. Geocon Project No. W1304-06-01 - 24 - March 18, 2021 7.13.3 Subdrainage pipes at the base of the retaining wall drainage system should outlet to an acceptable location via controlled drainage structures. Drainage should not be allowed to flow uncontrolled over descending slopes. 7.13.4 Moisture affecting below grade walls is one of the most common post-construction complaints. Poorly applied or omitted waterproofing can lead to efflorescence or standing water. Particular care should be taken in the design and installation of waterproofing to avoid moisture problems, or actual water seepage into the structure through any normal shrinkage cracks which may develop in the concrete walls, floor slab, foundations and/or construction joints. The design and inspection of the waterproofing is not the responsibility of the geotechnical engineer. A waterproofing consultant should be retained in order to recommend a product or method, which would provide protection to subterranean walls, floor slabs and foundations. 7.14 Elevator Pit Design 7.14.1 The elevator pit slab and retaining wall should be designed by the project structural engineer. Elevator pit walls may be designed in accordance with the recommendations in the Mat Foundation Design and Retaining Wall Design sections of this report (see Sections 7.5 and 7.11). 7.14.2 Additional active pressure should be added for a surcharge condition due to sloping ground, vehicular traffic or adjacent foundations and should be designed for each condition as the project progresses. 7.14.3 If retaining wall drainage is to be provided, the drainage system should be designed in accordance with the Retaining Wall Drainage section of this report (see Section 7.13) 7.14.4 It is suggested that the exterior walls and slab be waterproofed to prevent excessive moisture inside of the elevator pit. Waterproofing design and installation is not the responsibility of the geotechnical engineer. 7.15 Elevator Piston 7.15.1 If a plunger-type elevator piston is installed for this project, a deep drilled excavation will be required. It is important to verify that the drilled excavation is not situated immediately adjacent to a foundation or shoring pile, or the drilled excavation could compromise the existing foundation support or pile support, especially if the drilling is performed subsequent to the foundation or pile construction. Geocon Project No. W1304-06-01 - 25 - March 18, 2021 7.15.2 Casing will be required since caving is expected in the drilled excavation, and the contractor should be prepared to use casing and should have it readily available at the commencement of drilling activities. Continuous observation of the drilling and installation of the elevator piston by the Geotechnical Engineer (a representative of Geocon West, Inc.) is required. 7.15.3 The annular space between the piston casing and drilled excavation wall should be filled with a minimum of 1½-sack slurry pumped from the bottom up. As an alternative, pea gravel may be utilized. The use of soil to backfill the annular space is not acceptable. 7.16 Temporary Excavations 7.16.1 Excavations up to 26 feet in height are anticipated for excavation and construction of the proposed subterranean levels and foundation system. The excavations are expected to expose artificial fill and alluvial soils, which are subject to excessive caving where granular soils are encountered. Vertical excavations up to 5 feet in height may be attempted where loose soils or caving sands are not present, and where not surcharged by adjacent traffic or structures. 7.16.2 Vertical excavations greater than 5 feet or where surcharged by existing structures will require sloping or shoring measures in order to provide a stable excavation. Where sufficient space is available, temporary unsurcharged embankments could be sloped back at a uniform 1:1 slope gradient or flatter up to maximum height of 12 feet. A uniform slope does not have a vertical portion. Where space is limited, shoring measures will be required. Shoring data is provided in Section 7.17 of this report. 7.16.3 Where temporary construction slopes are utilized, the top of the slope should be barricaded to prevent vehicles and storage loads at the top of the slope within a horizontal distance equal to the height of the slope. If the temporary construction slopes are to be maintained during the rainy season, berms are suggested along the tops of the slopes where necessary to prevent runoff water from entering the excavation and eroding the slope faces. Geocon personnel should inspect the soils exposed in the cut slopes during excavation so that modifications of the slopes can be made if variations in the soil conditions occur. All excavations should be stabilized within 30 days of initial excavation. 7.17 Shoring – Soldier Pile Design and Installation 7.17.1 The following information on the design and installation of shoring is preliminary. Review of the final shoring plans and specifications should be made by this office prior to bidding or negotiating with a shoring contractor. Geocon Project No. W1304-06-01 - 26 - March 18, 2021 7.17.2 One method of shoring would consist of steel soldier piles, placed in drilled holes and backfilled with concrete. The steel soldier piles may also be installed utilizing high frequency vibration. Where maximum excavation heights are less than 12 feet the soldier piles are typically designed as cantilevers. Where excavations exceed 12 feet or are surcharged, soldier piles may require lateral bracing utilizing drilled tie-back anchors or raker braces to maintain an economical steel beam size and prevent excessive deflection. The size of the steel beam, the need for lateral bracing, and the acceptable shoring deflection should be determined by the project shoring engineer. 7.17.3 The design embedment of the shoring pile toes must be maintained during excavation activities. The toes of the perimeter shoring piles should be deepened to take into account any required excavations necessary for foundation excavations and/or adjacent drainage systems. 7.17.4 The proposed soldier piles may also be designed as permanent piles. The required pile depths, dimensions, and spacing should be determined and designed by the project structural and shoring engineers. All piles utilized for shoring can also be incorporated into a permanent retaining wall system (shotcrete wall) and should be designed in accordance with the earth pressure provided in the Retaining Wall Design section of this report (see Section 7.11). 7.17.5 Drilled cast-in-place soldier piles should be placed no closer than 3 diameters on center. The minimum diameter of the piles is 18 inches. Structural concrete should be used for the soldier piles below the excavation; lean-mix concrete may be employed above that level. As an alternative, lean-mix concrete may be used throughout the pile where the reinforcing consists of a wideflange section. The slurry must be of sufficient strength to impart the lateral bearing pressure developed by the wideflange section to the soil. For design purposes, an allowable passive value for the soils below the bottom plane of excavation may be assumed to be 330 psf per foot. Where piles are installed by vibration techniques, the passive pressure may be assumed to mobilize across a width equal to the two times the dimension of the beam flange. The allowable passive value may be doubled for isolated piles spaced a minimum of three times the pile diameter. To develop the full lateral value, provisions should be implemented to assure firm contact between the soldier piles and the undisturbed alluvium. Geocon Project No. W1304-06-01 - 27 - March 18, 2021 7.17.6 Groundwater was not encountered during site exploration. However, groundwater levels can fluctuate and may be different at the time of construction. It is not uncommon for groundwater or seepage conditions to develop where none previously existed. Therefore, the contractor should be prepared for groundwater during pile installation should the need arise. If more than 6 inches of water is present in the bottom of the excavation, a tremie is required to place the concrete into the bottom of the hole. A tremie should consist of a rigid, water-tight tube having a diameter of not less than 6 inches with a hopper at the top. The tube should be equipped with a device that will close the discharge end and prevent water from entering the tube while it is being charged with concrete. The tremie should be supported so as to permit free movement of the discharge end over the entire top surface of the work and to permit rapid lowering when necessary to retard or stop the flow of concrete. The discharge end should be closed at the start of the work to prevent water entering the tube and should be entirely sealed at all times, except when the concrete is being placed. The tremie tube should be kept full of concrete. The flow should be continuous until the work is completed, and the resulting concrete seal should be monolithic and homogeneous. The tip of the tremie tube should always be kept about 5 feet below the surface of the concrete and definite steps and safeguards should be taken to ensure that the tip of the tremie tube is never raised above the surface of the concrete. 7.17.7 A special concrete mix should be used for concrete to be placed below water. The design should provide for concrete with an unconfined compressive strength pounds per square inch (psi) of 1,000 psi over the initial job specification. An admixture that reduces the problem of segregation of paste/aggregates and dilution of paste should be included. The slump should be commensurate to any research report for the admixture, provided that it should also be the minimum for a reasonable consistency for placing when water is present. 7.17.8 Casing will be required since caving is expected, and the contractor should have casing available prior to commencement of drilling activities When casing is used, extreme care should be employed so that the pile is not pulled apart as the casing is withdrawn. At no time should the distance between the surface of the concrete and the bottom of the casing be less than 5 feet. As an alternative, piles may be vibrated into place; however, there is always a risk that excessive vibrations in sandy soils could induce settlements and distress to adjacent offsite improvements. Continuous observation of the drilling and pouring of the piles by the Geotechnical Engineer (a representative of Geocon West, Inc.), is required. 7.17.9 If a vibratory method of solider pile installation is utilized, predrilling may be performed prior to installation of the steel beams. If predrilling is performed, it is recommended that the bore diameter be at least 2 inches smaller than the largest dimension of the pile to prevent excessive loss in the frictional component of the pile capacity. Predrilling should not be conducted below the proposed excavation bottom. Geocon Project No. W1304-06-01 - 28 - March 18, 2021 7.17.10 If a vibratory method is utilized, the owner should be aware of the potential risks associated with vibratory efforts, which typically involve inducing settlement within the vicinity of the pile which could result in a potential for damage to existing improvements in the area. 7.17.11 The level of vibration that results from the installation of the piles should not exceed a threshold where occupants of nearby structures are disturbed, despite higher vibration tolerances that a building may endure without deformation or damage. The main parameter used for vibration assessment is peak particle velocity in units of inch per second (in/sec). The acceptable range of peak particle velocity should be evaluated based on the age and condition of adjacent structures, as well as the tolerance of human response to vibration. 7.17.12 Based on Table 19 of the Transportation and Construction Induced Vibration Guidance Manual (Caltrans 2013), a continuous source of vibrations (ex. vibratory pile driving) which generates a maximum peak particle velocity of 0.5 in/sec is considered tolerable for modern industrial/commercial buildings and new residential structures. The Client should be aware that a lower value may be necessary if older or fragile structures are in the immediate vicinity of the site. 7.17.13 Vibrations should be monitored and record with seismographs during pile installation to detect the magnitude of vibration and oscillation experienced by adjacent structures. If the vibrations exceed the acceptable range during installation, the shoring contractor should modify the installation procedure to reduce the values to within the acceptable range. Vibration monitoring is not the responsibility of the Geotechnical Engineer. 7.17.14 Geocon does not practice in the field of vibration monitoring. If construction techniques will be implemented, it is recommended that qualified consultant be retained to provide site specific recommendations for vibration thresholds and monitoring. 7.17.15 The frictional resistance between the soldier piles and retained soil may be used to resist the vertical component of the load. The coefficient of friction may be taken as 0.40 based on uniform contact between the steel beam and lean-mix concrete and retained earth. The portion of soldier piles below the plane of excavation may also be employed to resist the downward loads. The downward capacity may be determined using a frictional resistance of 475 psf per foot. 7.17.16 Due to the nature of the site soils, it is expected that continuous lagging between soldier piles will be required. However, it is recommended that the exposed soils be observed by the Geotechnical Engineer (a representative of Geocon West, Inc.), to verify the presence of any competent, cohesive soils and the areas where lagging may be omitted. Geocon Project No. W1304-06-01 - 29 - March 18, 2021 7.17.17 The time between lagging excavation and lagging placement should be as short as possible soldier piles should be designed for the full-anticipated pressures. Due to arching in the soils, the pressure on the lagging will be less. It is recommended that the lagging be designed for the full design pressure but be limited to a maximum of 400 psf. 7.17.18 For the design of unbraced shoring, it is recommended that an equivalent fluid pressure be utilized for design. A trapezoidal distribution of lateral earth pressure may be used where shoring will be restrained by bracing or tie backs. The recommended active and trapezoidal pressure are provided in the following table. A diagram depicting the trapezoidal pressure distribution of lateral earth pressure is provided below the table. HEIGHT OF SHORING (FEET) EQUIVALENT FLUID PRESSURE (Pounds Per Cubic Foot) (ACTIVE PRESSURE) EQUIVALENT FLUID PRESSURE Trapezoidal (Where H is the height of the shoring in feet) Up to 15 27 17H 16-26 39 24H 7.17.19 Where a combination of sloped embankment and shoring is utilized, the pressure will be greater and must be determined for each combination. Additional active pressure should be added for a surcharge condition due to sloping ground, vehicular traffic, or adjacent structures and must be determined for each combination. Trapezoidal Distribution of Pressure H 0.2H 0.2H 0.6H Geocon Project No. W1304-06-01 - 30 - March 18, 2021 7.17.20 It is recommended that line-load surcharges from adjacent wall footings, use horizontal pressures generated from NAV-FAC DM 7.2. The governing equations are: ܨ݋ݎ ݔ ܪൗ ൑ 0.4 ߪுሺݖሻ ൌ 0.20 ൈ ቀݖ ܪቁ ൤0.16 ൅ ቀݖ ܪቁଶ൨ ଶ ൈ ܳ௅ ܪ and ܨ݋ݎ ݔ ܪൗ ൐ 0.4 ߪுሺݖሻ ൌ 1.28 ൈ ቀݔ ܪቁଶ ൈ ቀݖ ܪቁ ൤ቀݔ ܪቁଶ ൅ ቀݖ ܪቁଶ൨ ଶ ൈ ܳ௅ ܪ where x is the distance from the face of the excavation or wall to the vertical line-load, H is the distance from the bottom of the footing to the bottom of excavation or wall, z is the depth at which the horizontal pressure is desired, QL is the vertical line-load and σHሺzሻ is the horizontal pressure at depth z. 7.17.21 It is recommended that vertical point-loads, from construction equipment outriggers or adjacent building columns use horizontal pressures generated from NAV-FAC DM 7.2. The governing equations are: ܨ݋ݎ ݔ ܪൗ ൑ 0.4 ߪுሺݖሻ ൌ 0.28 ൈ ቀ ݖ ܪቁଶ ൤0.16 ൅ ቀݖ ܪቁଶ൨ ଷ ൈ ܳ௉ ܪଶ and ܨ݋ݎ ݔ ܪൗ ൐ 0.4 ߪுሺݖሻ ൌ 1.77 ൈ ቀݔ ܪቁଶ ൈ ቀݖ ܪቁଶ ൤ቀݔܪቁଶ ൅ ቀݖܪቁଶ൨ ଷ ൈ ܳ௉ ܪଶ then ߪᇱு ሺݖሻ ൌ ߪுሺݖሻܿ݋ݏଶ ሺ1.1ߠሻ where x is the distance from the face of the excavation/wall to the vertical point-load, H is distance from the outrigger/bottom of column footing to the bottom of excavation, z is the depth at which the horizontal pressure is desired, Qp is the vertical point-load, σHሺzሻ is the horizontal pressure at depth z, ϴ is the angle between a line perpendicular to the excavation/wall and a line from the point-load to location on the excavation/wall where the surcharge is being evaluated, and σHሺzሻ is the horizontal pressure at depth z. Geocon Project No. W1304-06-01 - 31 - March 18, 2021 7.17.22 In addition to the recommended earth pressure, the upper 10 feet of the shoring adjacent to the street or driveway areas should be designed to resist a uniform lateral pressure of 100 psf, acting as a result of an assumed 300 psf surcharge behind the shoring due to normal street traffic. If the traffic is kept back at least 10 feet from the shoring, the traffic surcharge may be neglected. 7.17.23 It is difficult to accurately predict the amount of deflection of a shored embankment. It should be realized that some deflection will occur. It is recommended that the deflection be minimized to prevent damage to existing structures and adjacent improvements. Where public rights-of-way are present or adjacent offsite structures do not surcharge the shoring excavation, the shoring deflection should be limited to less than 1 inch at the top of the shored embankment. Where offsite structures are within the shoring surcharge area it is recommended that the beam deflection be limited to less than ½ inch at the elevation of the adjacent offsite foundation, and no deflection at all if deflections will damage existing structures. The allowable deflection is dependent on many factors, such as the presence of structures and utilities near the top of the embankment, and will be assessed and designed by the project shoring engineer. 7.17.24 Because of the depth of the excavation, some means of monitoring the performance of the shoring system is suggested. The monitoring should consist of periodic surveying of the lateral and vertical locations of the tops of all soldier piles and the lateral movement along the entire lengths of selected soldier piles. 7.17.25 Due to the depth of the excavation and proximity to adjacent structures, it is suggested that prior to excavation the existing improvements be inspected, and their present condition be documented. For documentation purposes, photographs should be taken of preconstruction distress conditions and level surveys of adjacent grade and pavement should be considered. During excavation activities, the adjacent structures and pavement should be periodically inspected for signs of distress. In the event that distress or settlement is observed, an investigation should be performed, and corrective measures taken so that continued or worsened distress or settlement is mitigated. Documentation and monitoring of the offsite structures and improvements is not the responsibility of the geotechnical engineer. 7.18 Temporary Tie-Back Anchors 7.18.1 Temporary tie-back anchors may be used with the solider pile wall system to resist lateral loads. Post-grouted friction anchors are recommended. For design purposes, it may be assumed that the active wedge adjacent to the shoring is defined by a plane drawn 35 degrees with the vertical through the bottom plane of the excavation. Friction anchors should extend a minimum of 20 feet beyond the potentially active wedge and to greater lengths if necessary to develop the desired capacities. The locations and depths of all offsite utilities should be thoroughly checked and incorporated into the drilling angle design for the tie-back anchors. Geocon Project No. W1304-06-01 - 32 - March 18, 2021 7.18.2 The capacities of the anchors should be determined by testing of the initial anchors as outlined in a following section. Only the frictional resistance developed beyond the active wedge would be effective in resisting lateral loads. Anchors should be placed at least 6 feet on center to be considered isolated. For preliminary design purposes, it is estimated that drilled friction anchors constructed without utilizing post-grouting techniques will develop average skin frictions as follows:  7 feet below the top of the excavation – 880 pounds per square foot  15 feet below the top of the excavation – 1,500 pounds per square foot 7.18.3 Depending on the techniques utilized, and the experience of the contractor performing the installation, a maximum allowable friction capacity of 3.2 kips per linear foot for post-grouted anchors (for a minimum 20-foot length beyond the active wedge) may be assumed for design purposes. Only the frictional resistance developed beyond the active wedge should be utilized in resisting lateral loads. Higher capacities may be possible but must be verified by testing. 7.19 Anchor Installation 7.19.1 Tie-back anchors are typically installed between 20 and 40 degrees below the horizontal; however, occasionally alternative angles are necessary to avoid existing improvements and utilities. The locations and depths of all offsite utilities should be thoroughly checked prior to design and installation of the tie-back anchors. Caving of the anchor shafts, particularly within sand and gravel deposits or seepage zones, should be anticipated during installation and provisions should be implemented in order to minimize such caving. It is suggested that hollow-stem auger drilling equipment be used to install the anchors. The anchor shafts should be filled with concrete by pumping from the tip out, and the concrete should extend from the tip of the anchor to the active wedge. In order to minimize the chances of caving, it is recommended that the portion of the anchor shaft within the active wedge be backfilled with sand before testing the anchor. This portion of the shaft should be filled tightly and flush with the face of the excavation. The sand backfill should be placed by pumping; the sand may contain a small amount of cement to facilitate pumping. 7.20 Anchor Testing 7.20.1 All of the anchors should be tested to at least 150 percent of design load. The total deflection during this test should not exceed 12 inches. The rate of creep under the 150 percent test load should not exceed 0.1 inch over a 15-minute period in order for the anchor to be approved for the design loading. Geocon Project No. W1304-06-01 - 33 - March 18, 2021 7.20.2 At least 10 percent of the anchors should be selected for "quick" 200 percent tests and three additional anchors should be selected for 24-hour 200 percent tests. The purpose of the 200 percent tests is to verify the friction value assumed in design. The anchors should be tested to develop twice the assumed friction value. These tests should be performed prior to installation of additional tiebacks. Where satisfactory tests are not achieved on the initial anchors, the anchor diameter and/or length should be increased until satisfactory test results are obtained. 7.20.3 The total deflection during the 24-hour 200 percent test should not exceed 12 inches. During the 24-hour tests, the anchor deflection should not exceed 0.75 inches measured after the 200 percent test load is applied. 7.20.4 For the "quick" 200 percent tests, the 200 percent test load should be maintained for 30 minutes. The total deflection of the anchor during the 200 percent quick tests should not exceed 12 inches; the deflection after the 200 percent load has been applied should not exceed 0.25 inch during the 30-minute period. 7.20.5 After a satisfactory test, each anchor should be locked-off at the design load. This should be verified by rechecking the load in the anchor. The load should be within 10 percent of the design load. A representative of this firm should observe the installation and testing of the anchors. 7.21 Internal Bracing 7.21.1 Rakers may be utilized to brace the soldier piles in lieu of tieback anchors. The raker bracing could be supported laterally by temporary concrete footings (deadmen) or by the permanent, interior footings. For design of such temporary footings or deadmen, poured with the bearing surface normal to rakers inclined at 45 degrees, a bearing value of 2,000 psf may be used, provided the shallowest point of the footing is at least one foot below the lowest adjacent grade. The structural engineer should review the shoring plans to determine if raker footings conflict with the structural foundation system. The client should be aware that the utilization of rakers could significantly impact the construction schedule due to their intrusion into the construction site and potential interference with equipment. Geocon Project No. W1304-06-01 - 34 - March 18, 2021 7.22 Stormwater Infiltration 7.22.1 During the February 8, 2021 site exploration, boring B4 was utilized to perform percolation testing. The boring was advanced to the depth listed in the table below. Slotted casing was placed in the boring, and the annular space between the casing and excavation was filled with filter pack. The boring was then filled with water to pre-saturate the soils. On February 9, 2021, after pre-saturating the soils, the casing was refilled with water and percolation test readings were performed after repeated flooding of the cased excavation. Based on the test results, the measured percolation rate and design infiltration rate, for the earth materials encountered, are provided in the following table. These values have been calculated in accordance with the Boring Percolation Test Procedure in the County of Los Angeles Department of Public Works GMED Guidelines for Geotechnical Investigation and Reporting, Low Impact Development Stormwater Infiltration (June 2017). Percolation test field data and calculation of the measured percolation rate and design infiltration rate are provided on Figures 7. Boring Soil Type Infiltration Depth (ft) Measured Percolation Rate (in / hour) Design Infiltration Rate (in / hour) B4 SW 20-30½ 8.78 4.39 7.22.2 Based on the test method utilized (Boring Percolation Test), the reduction factor RFt may be taken as 2.0 in the infiltration system design. Based on the number of tests performed and consistency of the soils throughout the site, it is suggested that the reduction factor RFv be taken as 1.0. In addition, provided proper maintenance is performed to minimize long-term siltation and plugging, the reduction factor RFs may be taken as 1.0. 7.22.3 The results of the percolation testing in the table above indicate that the infiltration rate for soils encountered at the depth and location indicated in the table above are considered conductive to infiltration, and it is our opinion that the site is suitable for infiltration of stormwater. 7.22.4 It is our further opinion that infiltration of stormwater and will not induce excessive hydro-consolidation, will not create a perched groundwater condition, will not affect soil structure interaction of existing or proposed foundations due to expansive soils, will not saturate soils supported by existing retaining walls, and will not increase the potential for liquefaction. Resulting settlements are anticipated to be less than ¼ inch, if any. If infiltration is planned for any location other than where the above testing was performed, additional field and laboratory testing may be required. Geocon Project No. W1304-06-01 - 35 - March 18, 2021 7.22.5 The infiltration system must be located such that the closest distance between an adjacent foundation is at least 15 feet in all directions from the zone of saturation. The zone of saturation may be assumed to project downward from the discharge of the infiltration facility at a gradient of 1:1. Additional property line or foundation setbacks may be required by the governing jurisdiction and should be incorporated into the stormwater infiltration system design as necessary. 7.22.6 Where a 15-foot horizontal setback cannot be maintained between the infiltration system and an adjacent footing, and the infiltration system penetrates below the foundation influence line, the proposed stormwater infiltration system must be designed to resist the surcharge from the adjacent foundation. The foundation surcharge line may be assumed to project down away from the bottom of the foundation at a 1:1 gradient 7.22.7 Subsequent to the placement of the infiltration system, it is acceptable to backfill the resulting void space between the excavation sidewalls and the infiltration system with minimum 2-sack slurry provided the slurry is not placed in the infiltration zone. It is recommended that pea gravel be utilized adjacent to the infiltration zone so communication of water to the soil is not hindered. 7.22.8 The design drawings should be reviewed and approved by the Geotechnical Engineer. The installation of the stormwater infiltration system should be observed and approved in writing by the Geotechnical Engineer (a representative of Geocon). 7.23 Surface Drainage 7.23.1 Proper surface drainage is critical to the future performance of the project. Uncontrolled infiltration of irrigation excess and storm runoff into the soils can adversely affect the performance of the planned improvements. Saturation of a soil can cause it to lose internal shear strength and increase its compressibility, resulting in a change in the original designed engineering properties. Proper drainage should be maintained at all times. 7.23.2 All site drainage should be collected and controlled in non-erosive drainage devices. Drainage should not be allowed to pond anywhere on the site, and especially not against any foundation or retaining wall. The site should be graded and maintained such that surface drainage is directed away from structures in accordance with 2019 CBC 1804.4 or other applicable standards. In addition, drainage should not be allowed to flow uncontrolled over any descending slope. Discharge from downspouts, roof drains and scuppers are not recommended onto unprotected soils within 5 feet of the building perimeter. Planters which are located adjacent to foundations should be sealed to prevent moisture intrusion into the soils providing foundation support. Landscape irrigation is not recommended within 5 feet of the building perimeter footings except when enclosed in protected planters. Geocon Project No. W1304-06-01 - 36 - March 18, 2021 7.23.3 Positive site drainage should be provided away from structures, pavement, and the tops of slopes to swales or other controlled drainage structures. The building pad and pavement areas should be fine graded such that water is not allowed to pond. 7.23.4 Landscaping planters immediately adjacent to paved areas are not recommended due to the potential for surface or irrigation water to infiltrate the pavement's subgrade and base course. Either a subdrain, which collects excess irrigation water and transmits it to drainage structures, or an impervious above-grade planter boxes should be used. In addition, where landscaping is planned adjacent to the pavement, it is recommended that consideration be given to providing a cutoff wall along the edge of the pavement that extends at least 12 inches below the base material. 7.24 Plan Review 7.24.1 Grading, foundation, and shoring plans should be reviewed by the Geotechnical Engineer (a representative of Geocon West, Inc.), prior to finalization to verify that the plans have been prepared in substantial conformance with the recommendations of this report and to provide additional analyses or recommendations. Geocon Project No. W1304-06-01 March 18, 2021 LIMITATIONS AND UNIFORMITY OF CONDITIONS 1. The recommendations of this report pertain only to the site investigated and are based upon the assumption that the soil conditions do not deviate from those disclosed in the investigation. If any variations or undesirable conditions are encountered during construction, or if the proposed construction will differ from that anticipated herein, Geocon West, Inc. should be notified so that supplemental recommendations can be given. The evaluation or identification of the potential presence of hazardous or corrosive materials was not part of the scope of services provided by Geocon West, Inc. 2. This report is issued with the understanding that it is the responsibility of the owner, or of his representative, to ensure that the information and recommendations contained herein are brought to the attention of the architect and engineer for the project and incorporated into the plans, and the necessary steps are taken to see that the contractor and subcontractors carry out such recommendations in the field. 3. The findings of this report are valid as of the date of this report. However, changes in the conditions of a property can occur with the passage of time, whether they are due to natural processes or the works of man on this or adjacent properties. In addition, changes in applicable or appropriate standards may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the findings of this report may be invalidated wholly or partially by changes outside our control. Therefore, this report is subject to review and should not be relied upon after a period of three years. 4. The firm that performed the geotechnical investigation for the project should be retained to provide testing and observation services during construction to provide continuity of geotechnical interpretation and to check that the recommendations presented for geotechnical aspects of site development are incorporated during site grading, construction of improvements, and excavation of foundations. If another geotechnical firm is selected to perform the testing and observation services during construction operations, that firm should prepare a letter indicating their intent to assume the responsibilities of project geotechnical engineer of record. A copy of the letter should be provided to the regulatory agency for their records. In addition, that firm should provide revised recommendations concerning the geotechnical aspects of the proposed development, or a written acknowledgement of their concurrence with the recommendations presented in our report. They should also perform additional analyses deemed necessary to assume the role of Geotechnical Engineer of Record. Geocon Project No. W1304-06-01 March 18, 2021 LIST OF REFERENCES Arcadia, City of, 2010, Chapter 8: Safety Element, Arcadia General Plan. California Division of Mines and Geology, 1999, State of California Seismic Hazard Zones, Mount Wilson Quadrangle, Official Map Released March 25, 1999. California Division of Mines and Geology, 1998, Seismic Hazard Evaluation of the Mount Wilson 7.5-Minute Quadrangle, Los Angeles County, California, Open File Report 98-21. California Geologic Energy Management Division, 2021, CalGEM Resources Well Finder, http://maps.conservation.ca.gov.doggr/index.html#close. California Geological Survey, 2021a, CGS Information Warehouse, Regulatory Map Portal, http://maps.conservation.ca.gov/cgs/informationwarehouse/index.html?map=regulatorymaps. California Geological Survey, 2021b, Earthquake Zones of Required Investigation, https://maps.conservation.ca.gov/cgs/EQZApp/app/. California Geological Survey, 2018, Earthquake Fault Zones, A Guide for Government Agencies, Property Owners/Developers, and Geoscience Practitioners for Assessing Fault Rupture Hazards in California, Special Publication 42, Revised 2018. California Geological Survey, 2017, Zones of Required Investigations, Mount Wilson Quadrangle, Revised Official Map, dated June 15, 2017. California Geological Survey, 2016, The Raymond Fault in the Mt. Wilson and El Monte Quadrangles, Los Angeles County, California, Fault Evaluation Report FER-264, by Jerome A. Treiman, dated December 7, 2016. California Geological Survey, 2010, Geologic Compilation of Quaternary Surficial Deposits in Southern California, San Gabriel River Hydrogeologic Unit, A Project for the Department of Water Resources by the California Geological Survey, Plate 15, CGS Special Report 217, dated July 2010. Crook, R., Jr., Allen, C. R., Kamb, B., Payne, C. M., and Proctor, R. J., 1987, Recent Reverse Faulting in the Transverse Ranges, California, U.S. Geological Survey Professional Paper 1339. FEMA, 2021, Online Flood Hazard Maps, http://www.esri.com/hazards/index.html. Jennings, C. W. and Bryant, W. A., 2010, Fault Activity Map of California, California Geological Survey Geologic Data Map No. 6. Leighton and Associates, Inc., 1990, Technical Appendix to the Safety Element of the Los Angeles County General Plan, Hazard Reduction in Los Angeles County. Los Angeles County Department of Public Works, 2021a, Ground Water Wells Website, http://dpw2.co.la.ca.us/website/wells/viewer.asp. Los Angeles County Department of Public Works, 2021b, Flood Zone Determination Website, http://dpw.lacounty.gov/apps/wmd/floodzone/map.htm. Geocon Project No. W1304-06-01 March 18, 2021 LIST OF REFERENCES (Continued) Toppozada, T., Branum, D., Petersen, M, Hallstrom, C., and Reichle, M., 2000, Epicenters and Areas Damaged by M> 5 California Earthquakes, 1800 – 1999, California Geological Survey, Map Sheet 49. U.S. Geological Survey and California Geological Survey, 2006, Quaternary Fault and Fold Database for the United States, accessed March 5, 2021 from USGS web site: http//earthquake.usgs.gov/hazards/qfaults/. Ziony, J. I., and Jones, L. M., 1989, Map Showing Late Quaternary Faults and 1978–1984 Seismicity of the Los Angeles Region, California, U.S. Geological Survey Miscellaneous Field Studies Map MF-1964. REFERENCE: U.S.G.S. TOPOGRAPHIC MAPS, 7.5 MINUTE SERIES, MT. WILSON, CA QUADRANGLE LATITUDE: 34.141703 LONGTITUDE: -118.030544 FIG. 1 VICINITY MAP PHONE (818) 841-8388 - FAX (818) 841-17043303 N. SAN FERNANDO BLVD. - SUITE 100 - BURBANK, CA 91504 ENVIRONMENTAL GEOTECHNICAL MATERIALS CHECKED BY: SFKDRAFTED BY: RA PROJECT NO. W1304-06-01MARCH 2021 ARCADIA, CALIFORNIA 150 N. SANTA ANITA AVENUE SITE 0 100' PHONE (818) 841-8388 - FAX (818) 841-1704 3303 N. SAN FERNANDO BLVD. - SUITE 100 - BURBANK, CA 91504 ENVIRONMENTAL GEOTECHNICAL MATERIALS SITE PLAN FIG. 2APROJECT NO. W1304-06-01MARCH 2021 50' DRAFTED BY: PZ 150 N. SANTA ANITA AVENUE ARCADIA, CALIFORNIA CHECKED BY: JTA LEGEND Approximate Location of Boring B4 Approximate Location of Property LineB1 B2 B4 B3 A A' Location of Existing Structures 0 60'PHONE (818) 841-8388 - FAX (818) 841-1704 3303 N. SAN FERNANDO BLVD. - SUITE 100 - BURBANK, CA 91504 ENVIRONMENTAL GEOTECHNICAL MATERIALS CROSS SECTION FIG. 2BPROJECT NO. W1304-06-01MARCH 2021 30' DRAFTED BY: PZ 150 N. SANTA ANITA AVENUE ARCADIA, CALIFORNIA CHECKED BY: JTA SITE LATITUDE: 34.141703 LONGTITUDE: -118.030544 0 12 24 Miles Reference: Jennings, C.W. and Bryant, W. A., 2010, Fault Activity Map of California, California Geological Survey Geologic Data Map No. 6. REGIONAL FAULT MAP ARCADIA, CALIFORNIA PROJECT NO. W1304-06-01MARCH 2021 FIG. 3 150 NORTH SANTA ANITA AVENUE PHONE (818) 841-8388 - FAX (818) 841-1704 3303 N. SAN FERNANDO BLVD. - SUITE 100 - BURBANK, CA 91504 ENVIRONMENTAL GEOTECHNICAL MATERIALS CHECKED BY: SFKDRAFTED BY: RA SITE DRAFTED BY: RA CHECKED BY: SFK LATITUDE: 34.141703 LONGTITUDE: -118.030544 PHONE (818) 841-8388 - FAX (818) 841-1704 3303 N. SAN FERNANDO BLVD. - SUITE 100 - BURBANK, CA 91504 ENVIRONMENTAL GEOTECHNICAL MATERIALS REGIONAL SEISMICITY MAP FIG. 402040Miles Reference: Toppozada, T., Branum, D., Petersen, M., Hallstrom, C., Cramer, C., and Reichle, M., 2000, Epicenters and Areas Damaged by M>5 California Earthquakes, 1800 - 1999, California Geological Survey, Map Sheet 49. 150 N. SANTA ANITA AVENUE ARCADIA, CALIFORNIA PROJECT NO. W1304-06-01MARCH 2021 3/4" CRUSHED ROCK MIRAFI 140N OR EQUIVALENT FILTER FABRIC ENVELOPE 4" DIA. PERFORATED ABS OR ADS PIPE - EXTEND TO RETAINING WALL DRAINAGE SYSTEM WATERPROOF WALL PROPERLY COMPACTED BACKFILL GROUND SURFACE FOUNDATION NO SCALE RETAINING WALL DRAIN DETAIL FIG. 5DRAFTED BY: PZ CHECKED BY: JTA PROJECT NO. W1304-06-01MARCH 2021 150 N. SANTA ANITA AVENUE ARCADIA, CALIFORNIAPHONE (818) 841-8388 - FAX (818) 841-1704 3303 N. SAN FERNANDO BLVD. - SUITE 100 - BURBANK, CA 91504 ENVIRONMENTAL GEOTECHNICAL MATERIALS RETAINING WALL FOUNDATION PROPERLY COMPACTED BACKFILL GROUND SURFACE 18" WATER PROOFING BY ARCHITECT DRAINAGE PANEL (J-DRAIN 1000 OR EQUIVALENT) 4" DIA. SCHEDULE 40 PERFORATED PVC PIPE EXTENDED TO APPROVED OUTLET (1 CU. FT./FT.) FILTER FABRIC ENVELOPE 3/4" CRUSHED ROCK MIRAFI 140N OR EQUIVALENT NO SCALE RETAINING WALL DRAIN DETAIL FIG. 6DRAFTED BY: PZ CHECKED BY: JTA PROJECT NO. W1304-06-01MARCH 2021 150 N. SANTA ANITA AVENUE ARCADIA, CALIFORNIAPHONE (818) 841-8388 - FAX (818) 841-1704 3303 N. SAN FERNANDO BLVD. - SUITE 100 - BURBANK, CA 91504 ENVIRONMENTAL GEOTECHNICAL MATERIALS Date: Boring/Test Number: Project Number: Diameter of Boring: 8 inches Project Location: Diameter of Casing: 2 inches Earth Description: Depth of Boring: 30.5 feet Tested By: Depth to Invert of BMP: 20 feet Liquid Description: Depth to Water Table: N/A feet Measurement Method: Depth to Initial Water Depth (d1): 240 inches Start Time for Pre-Soak: Water Remaining in Boring (Y/N): Start Time for Standard: Standard Time Interval Between Readings: 10 Reading Number Time Start (hh:mm) Time End (hh:mm) Elapsed Time time (min) Water Drop During Standard Time Interval, Δd (in) 1 8:08 AM 8:18 AM 10.0 94.8 2 8:19 AM 8:29 AM 10.0 93.6 3 8:34 AM 8:44 AM 10.0 93.6 4 8:47 AM 8:57 AM 10.0 93.6 5 9:00 AM 9:10 AM 10.0 93.6 * Calculations Below Based on Stabilized Readings Only Boring Radius, r: 4 inches Test Section Height, h: 126.0 inches A = 3217 in2 Reading 6 V = 4705 in3 Percolation Rate = 8.78 inches/hour Reading 7 V = 4705 in3 Percolation Rate = 8.78 inches/hour Reading 8 V = 4705 in3 Percolation Rate = 8.78 inches/hour Measured Percolation Rate = 8.78 inches/hour Reduction Factors Boring Percolation Test, RFt = 2 Site Variability, RFv = 1 Total Reduction Factor = 2 Long Term Siltation, RFs = 1 Design Infiltration Rate Design Infiltration Rate = 4.39 inches/hour FIGURE 7 Soil Description Notes Comments Stabilized Readings Achieved MEASURED PERCOLATION RATE & DESIGN INFILTRATION RATE CALCULATIONS* 2/9/2021 8:05 B4 No RA 2/9/2021 2/8/2021 12:30 BORING PERCOLATION TEST FIELD LOG W1304-06-01 SW Water Sounder 150 N. Santa Anita 𝑇𝑒𝑠𝑡 𝑆𝑒𝑐𝑡𝑖𝑜𝑛 𝑆𝑢𝑟𝑓𝑎𝑐𝑒 𝐴𝑟𝑒𝑎,𝐴 ൌ 2𝜋𝑟ℎ ൅ 𝜋𝑟ଶ 𝐷𝑖𝑠𝑐ℎ𝑎𝑟𝑔𝑒𝑑 𝑊𝑎𝑡𝑒𝑟 𝑉𝑜𝑙𝑢𝑚𝑒,𝑉 ൌ 𝜋𝑟ଶΔd 𝑃𝑒𝑟𝑐𝑜𝑙𝑎𝑡𝑖𝑜𝑛 𝑅𝑎𝑡𝑒 ൌ 𝑉𝐴⁄ ∆𝑇 𝐷𝑒𝑠𝑖𝑔𝑛 𝐼𝑛𝑓𝑖𝑙𝑡𝑟𝑎𝑡𝑖𝑜𝑛 𝑅𝑎𝑡𝑒 ൌ 𝑀𝑒𝑎𝑠𝑢𝑟𝑒𝑑 𝑃𝑒𝑟𝑐𝑜𝑙𝑎𝑡𝑖𝑜𝑛 𝑅𝑎𝑡𝑒 /𝑅𝐹 𝑇𝑜𝑡𝑎𝑙 𝑅𝑒𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝐹𝑎𝑐𝑡𝑜𝑟,𝑅𝐹 ൌ 𝑅𝐹௧ ൈ𝑅𝐹௩ ൈ𝑅𝐹௦ APPENDIX A Geocon Project No. W1304-06-01 March 18, 2021 APPENDIX A FIELD INVESTIGATION The site was explored on February 8, 2021 by excavating four 8-inch diameter borings to depths ranging from approximately 30½ to 40½ feet below the existing ground surface using a truck-mounted, hollow-stem auger drilling machine. Representative and relatively undisturbed samples were obtained by driving a 3 inch, O. D., California Modified Sampler into the “undisturbed” soil mass with blows from a 140-pound auto-hammer falling 30 inches. The California Modified Sampler was equipped with 1-inch high by 23/8-inch diameter brass sampler rings to facilitate soil removal and testing. Bulk samples were also obtained. The soil conditions encountered in the borings were visually examined, classified and logged in general accordance with the Unified Soil Classification System (USCS). The logs of the borings are presented on Figures A1 through A4. The logs depict the soil and geologic conditions encountered and the depth at which samples were obtained. The logs also include our interpretation of the conditions between sampling intervals. Therefore, the logs contain both observed and interpreted data. We determined the lines designating the interface between soil materials on the logs using visual observations, penetration rates, excavation characteristics and other factors. The transition between materials may be abrupt or gradual. Where applicable, the logs were revised based on subsequent laboratory testing. The locations of the borings are shown on Figure 2A. AC: 5" BASE: NONE ARTIFICIAL FILL Silty Sand, medium dense, slightly moist, dark brown, fine- to medium-grained, trace coarse-grained. ALLUVIUM Sand, poorly graded, dense, slightly moist, light brown, fine- to medium-grained. - medium dense, trace coarse-grained, 3" rock fragment - increase in coarse-grained sand - very dense - dense, trace fine gravel - medium dense, brown - dense, some fine gravel 4.9 6.2 3.2 8.3 3.6 8.7 5.3 SP B1@5' B1@10' B1@15' B1@20' BULK 20-30' B1@22.5' B1@25' B1@27.5' 51 28 37 50 (6") 65 50 82 120.6 106.0 111.0 97.6 115.4 99.5 122.6 SAMPLE NO. HOLLOW STEM AUGER ... WATER TABLE OR SEEPAGE DEPTH IN FEET ... DRIVE SAMPLE (UNDISTURBED) GEOCON -- 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 DR Y D E N S I T Y EQUIPMENT BORING 1 RA MO I S T U R E BY: (P . C . F . ) DATE COMPLETED ... SAMPLING UNSUCCESSFUL ... DISTURBED OR BAG SAMPLE SOIL CLASS (USCS) GR O U N D W A T E R SAMPLE SYMBOLS CO N T E N T ( % ) ... CHUNK SAMPLE 02/08/2021ELEV. (MSL.) PE N E T R A T I O N RE S I S T A N C E (B L O W S / F T * ) MATERIAL DESCRIPTION LI T H O L O G Y ... STANDARD PENETRATION TEST W1304-06-01 BORING LOGS.GPJFigure A1, Log of Boring 1, Page 1 of 2 NOTE: PROJECT NO. THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. W1304-06-01 - no fine gravel Sand, well-graded, dense, slightly moist, brown, fine- to coarse-grained. - increase in coarse-grained Total depth of boring: 40.5 feet Fill to 2 feet. No groundwater encountered. Backfilled with soil cuttings and tamped. Asphalt patched. *Penetration resistance for 140-pound hammer falling 30 inches by auto-hammer. 10.0 5.6 11.2 4.7 SP SW B1@30' B1@32.5' B1@35' B1@40' 63 59 62 60 101.5 113.1 101.4 114.8 SAMPLE NO. HOLLOW STEM AUGER ... WATER TABLE OR SEEPAGE DEPTH IN FEET ... DRIVE SAMPLE (UNDISTURBED) GEOCON -- 30 32 34 36 38 40 DR Y D E N S I T Y EQUIPMENT BORING 1 RA MO I S T U R E BY: (P . C . F . ) DATE COMPLETED ... SAMPLING UNSUCCESSFUL ... DISTURBED OR BAG SAMPLE SOIL CLASS (USCS) GR O U N D W A T E R SAMPLE SYMBOLS CO N T E N T ( % ) ... CHUNK SAMPLE 02/08/2021ELEV. (MSL.) PE N E T R A T I O N RE S I S T A N C E (B L O W S / F T * ) MATERIAL DESCRIPTION LI T H O L O G Y ... STANDARD PENETRATION TEST W1304-06-01 BORING LOGS.GPJFigure A1, Log of Boring 1, Page 2 of 2 NOTE: PROJECT NO. THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. W1304-06-01 AC: 5" BASE: NONE ARTIFICIAL FILL Silty Sand, medium dense, slightly moist, dark brown, fine-grained, trace medium- to coarse-grained. ALLUVIUM Sand, poorly graded, medium dense, slightly moist, light brown, fine-grained, trace medium- to coarse-grained. - increase in medium- to coarse-grained, trace coarse gravel (to 3") - dense, fine- to coarse-grained - very dense, moist, light brown to brown - dense, trace silt - medium dense, increase in fine-grained, trace medium- to coarse-grained - dense, reddish brown 2.3 4.5 2.2 2.8 3.1 6.4 6.2 SP B2@5' B2@10' B2@15' B2@20' B2@22.5' B2@25' B2@27.5' 29 29 61 50 (5.5") 84 45 58 106.4 111.5 123.9 115.5 136.3 110.1 119.0 SAMPLE NO. HOLLOW STEM AUGER ... WATER TABLE OR SEEPAGE DEPTH IN FEET ... DRIVE SAMPLE (UNDISTURBED) GEOCON -- 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 DR Y D E N S I T Y EQUIPMENT BORING 2 RA MO I S T U R E BY: (P . C . F . ) DATE COMPLETED ... SAMPLING UNSUCCESSFUL ... DISTURBED OR BAG SAMPLE SOIL CLASS (USCS) GR O U N D W A T E R SAMPLE SYMBOLS CO N T E N T ( % ) ... CHUNK SAMPLE 02/08/2021ELEV. (MSL.) PE N E T R A T I O N RE S I S T A N C E (B L O W S / F T * ) MATERIAL DESCRIPTION LI T H O L O G Y ... STANDARD PENETRATION TEST W1304-06-01 BORING LOGS.GPJFigure A2, Log of Boring 2, Page 1 of 2 NOTE: PROJECT NO. THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. W1304-06-01 - light brown, no silt Silty Sand, dense, moist, reddish brown, trace medium- to coarse-grained. Sand, well-graded, dense, moist, brown to light brown, fine-grained, trace medium- to coarse-grained. - very dense Total depth of boring: 40.5 feet Fill to 3 feet. No groundwater encountered. Backfilled with soil cuttings and tamped. Asphalt patched. *Penetration resistance for 140-pound hammer falling 30 inches by auto-hammer. 3.6 10.5 6.1 4.5 SP SM SW B2@30' B2@32.5' B2@35' B2@40' 52 51 62 50 (6") 116.8 113.6 105.1 88.3 SAMPLE NO. HOLLOW STEM AUGER ... WATER TABLE OR SEEPAGE DEPTH IN FEET ... DRIVE SAMPLE (UNDISTURBED) GEOCON -- 30 32 34 36 38 40 DR Y D E N S I T Y EQUIPMENT BORING 2 RA MO I S T U R E BY: (P . C . F . ) DATE COMPLETED ... SAMPLING UNSUCCESSFUL ... DISTURBED OR BAG SAMPLE SOIL CLASS (USCS) GR O U N D W A T E R SAMPLE SYMBOLS CO N T E N T ( % ) ... CHUNK SAMPLE 02/08/2021ELEV. (MSL.) PE N E T R A T I O N RE S I S T A N C E (B L O W S / F T * ) MATERIAL DESCRIPTION LI T H O L O G Y ... STANDARD PENETRATION TEST W1304-06-01 BORING LOGS.GPJFigure A2, Log of Boring 2, Page 2 of 2 NOTE: PROJECT NO. THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. W1304-06-01 AC: 5" BASE: NONE ARTIFICIAL FILL Silty Sand, medium dense, slightly moist, dark brown, fine-grained, trace medium- to coarse-grained. ALLUVIUM Sand, medium dense, slightly moist, brown, fine- to medium-grained, trace coarse gravel. - increase in coarse-grained - some coarse-grained - trace fine gravel - decrease in fine gravel Silty Sand, medium dense, moist, dark brown, fine-grained. Sand, poorly graded, medium dense, slightly moist, light brown, fine- to medium-grained, trace coarse-grained. - reddish brown, fine-grained, trace medium- to coarse-grained - fine- to coarse-grained, trace fine gravel 4.9 3.7 6.4 4.9 3.1 14.0 SP SM SP B3@2.5' B3@5' BULK 5-10' B3@10' B3@12.5' B3@15' B3@17.5' B3@20' B3@25' 29 29 29 47 52 38 53 85.6 114.9 100.9 110.4 122.3 111.8 SAMPLE NO. HOLLOW STEM AUGER ... WATER TABLE OR SEEPAGE DEPTH IN FEET ... DRIVE SAMPLE (UNDISTURBED) GEOCON -- 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 DR Y D E N S I T Y EQUIPMENT BORING 3 RA MO I S T U R E BY: (P . C . F . ) DATE COMPLETED ... SAMPLING UNSUCCESSFUL ... DISTURBED OR BAG SAMPLE SOIL CLASS (USCS) GR O U N D W A T E R SAMPLE SYMBOLS CO N T E N T ( % ) ... CHUNK SAMPLE 02/08/2021ELEV. (MSL.) PE N E T R A T I O N RE S I S T A N C E (B L O W S / F T * ) MATERIAL DESCRIPTION LI T H O L O G Y ... STANDARD PENETRATION TEST W1304-06-01 BORING LOGS.GPJFigure A3, Log of Boring 3, Page 1 of 2 NOTE: PROJECT NO. THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. W1304-06-01 - very dense Total depth of boring: 30.5 feet Fill to 4 feet. No groundwater encountered. Backfilled with soil cuttings and tamped. Asphalt patched. *Penetration resistance for 140-pound hammer falling 30 inches by auto-hammer. SPB3@30'50 (6") SAMPLE NO. HOLLOW STEM AUGER ... WATER TABLE OR SEEPAGE DEPTH IN FEET ... DRIVE SAMPLE (UNDISTURBED) GEOCON -- 30 DR Y D E N S I T Y EQUIPMENT BORING 3 RA MO I S T U R E BY: (P . C . F . ) DATE COMPLETED ... SAMPLING UNSUCCESSFUL ... DISTURBED OR BAG SAMPLE SOIL CLASS (USCS) GR O U N D W A T E R SAMPLE SYMBOLS CO N T E N T ( % ) ... CHUNK SAMPLE 02/08/2021ELEV. (MSL.) PE N E T R A T I O N RE S I S T A N C E (B L O W S / F T * ) MATERIAL DESCRIPTION LI T H O L O G Y ... STANDARD PENETRATION TEST W1304-06-01 BORING LOGS.GPJFigure A3, Log of Boring 3, Page 2 of 2 NOTE: PROJECT NO. THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. W1304-06-01 AC: 5" BASE: NONE ARTIFICIAL FILL Silty Sand, medium dense, moist, dark brown, fine-grained, trace medium-grained. ALLUVIUM Sand, poorly graded, medium dense, dry to slightly moist, light brown, fine- to medium-grained. - dry, fine- to coarse-grained - brown, trace fine gravel (to 3") - very dense, reddish brown, decrease in coarse-grained - medium dense, fine-grained, trace silt Sand, well-graded, dense, slightly moist, light brown, fine- to coarse-grained, trace fine to coarse gravel (to 3"). 2.6 4.6 3.7 3.1 7.4 4.9 4.5 2.9 SP SW B4@5' B4@10' B4@12.5' B4@15' B4@17.5' B4@20' B4@22.5' B4@25' 22 31 29 41 50 (5.5") 34 49 97 116.7 102.5 115.8 110.3 81.1 111.1 114.2 121.4 SAMPLE NO. HOLLOW STEM AUGER ... WATER TABLE OR SEEPAGE DEPTH IN FEET ... DRIVE SAMPLE (UNDISTURBED) GEOCON -- 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 DR Y D E N S I T Y EQUIPMENT BORING 4 RA MO I S T U R E BY: (P . C . F . ) DATE COMPLETED ... SAMPLING UNSUCCESSFUL ... DISTURBED OR BAG SAMPLE SOIL CLASS (USCS) GR O U N D W A T E R SAMPLE SYMBOLS CO N T E N T ( % ) ... CHUNK SAMPLE 02/08/2021ELEV. (MSL.) PE N E T R A T I O N RE S I S T A N C E (B L O W S / F T * ) MATERIAL DESCRIPTION LI T H O L O G Y ... STANDARD PENETRATION TEST W1304-06-01 BORING LOGS.GPJFigure A4, Log of Boring 4, Page 1 of 2 NOTE: PROJECT NO. THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. W1304-06-01 Total depth of boring: 30.5 feet Fill to 2.5 feet. No groundwater encountered. Percolation testing performed. Backfilled with soil cuttings and tamped. Asphalt patched. *Penetration resistance for 140-pound hammer falling 30 inches by auto-hammer. 2.8SWB4@30'50 (6") 123.8 SAMPLE NO. HOLLOW STEM AUGER ... WATER TABLE OR SEEPAGE DEPTH IN FEET ... DRIVE SAMPLE (UNDISTURBED) GEOCON -- 30 DR Y D E N S I T Y EQUIPMENT BORING 4 RA MO I S T U R E BY: (P . C . F . ) DATE COMPLETED ... SAMPLING UNSUCCESSFUL ... DISTURBED OR BAG SAMPLE SOIL CLASS (USCS) GR O U N D W A T E R SAMPLE SYMBOLS CO N T E N T ( % ) ... CHUNK SAMPLE 02/08/2021ELEV. (MSL.) PE N E T R A T I O N RE S I S T A N C E (B L O W S / F T * ) MATERIAL DESCRIPTION LI T H O L O G Y ... STANDARD PENETRATION TEST W1304-06-01 BORING LOGS.GPJFigure A4, Log of Boring 4, Page 2 of 2 NOTE: PROJECT NO. THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES. W1304-06-01 APPENDIX B Geocon Project No. W1304-06-01 March 18, 2021 APPENDIX B LABORATORY TESTING Laboratory tests were performed in accordance with generally accepted test methods of the “American Society for Testing and Materials (ASTM)”, or other suggested procedures. Selected samples were tested for direct shear strength, consolidation, corrosivity, and in-place dry density and moisture content. The results of the laboratory tests are summarized in Figures B1 through B20. The in-place dry density and moisture content of the samples tested are presented on the boring logs, Appendix A. Project No.: W1304-06-01 14.6 DIRECT SHEAR TEST RESULTS 150 N. Santa Anita Avenue Arcadia, CaliforniaConsolidated Drained ASTM D-3080 Checked by: PZ 14.5 March 2021 Figure B1 Ultimate 100 38.1 Final Moisture Content (%) 18.9 31.6 30.2 Peak 300 39.5 Soil Height Before Shearing (in.) 1.2 1.2 1.2 C (psf)Initial Degree of Saturation (%) 22.5 Strength Parameters Initial Dry Density (pcf) 97.2 110.5 109.9 Light Brown Sand (SP)Ring Inside Diameter (in.) 2.375 2.375 2.375 Initial Moisture Content (%) 6.1 6.2 6.0 Soil Identification:Initial Sample Height (in.) 1.0 1.0 1.0 0.05 Depth (ft) 10 Shear Stress @ End of Test (ksf) 0.86 3.32 4.00 Sample Type:Ring Deformation Rate (in./min.) 0.05 0.05 4.42 Boring No. B1 Normal Strest (kip/ft2) 1 3 5 Sample No. B1@10'Peak Shear Stress (kip/ft²) 1.12 3.44 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Sh e a r S t r e s s ( k s f ) Normal Stress (ksf) Project No.: W1304-06-01 4.51 Boring No. B4 Normal Strest (kip/ft2) 1 3 5 Sample No. B4@10'Peak Shear Stress (kip/ft²) 1.22 3.94 0.05 Depth (ft) 10 Shear Stress @ End of Test (ksf) 0.72 2.87 4.07 Sample Type:Ring Deformation Rate (in./min.) 0.05 0.05 Soil Identification:Initial Sample Height (in.) 1.0 1.0 1.0 Light Brown Sand (SP)Ring Inside Diameter (in.) 2.375 2.375 2.375 Initial Moisture Content (%) 5.9 4.6 5.9 Strength Parameters Initial Dry Density (pcf) 98.4 104.1 101.5 20.1 24.0 Peak 400 39.4 Soil Height Before Shearing (in.) 1.2 1.2 1.2 C (psf)Initial Degree of Saturation (%) 22.2 Ultimate 0 39.4 Final Moisture Content (%) 18.9 16.3 DIRECT SHEAR TEST RESULTS 150 N. Santa Anita Avenue Arcadia, CaliforniaConsolidated Drained ASTM D-3080 Checked by: PZ 16.3 March 2021 Figure B2 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Sh e a r S t r e s s ( k s f ) Normal Stress (ksf) Project No.: W1304-06-01 4.25 Boring No. B3 Normal Strest (kip/ft2) 1 3 5 Sample No. B3@12.5'Peak Shear Stress (kip/ft²) 1.11 2.63 0.05 Depth (ft) 12.5 Shear Stress @ End of Test (ksf) 0.81 2.22 3.85 Sample Type:Ring Deformation Rate (in./min.) 0.05 0.05 Soil Identification:Initial Sample Height (in.) 1.0 1.0 1.0 Brown Sand (SP)Ring Inside Diameter (in.) 2.375 2.375 2.375 Initial Moisture Content (%) 5.8 6.4 6.4 Strength Parameters Initial Dry Density (pcf) 99.7 98.8 100.4 24.5 25.4 Peak 305 38.1 Soil Height Before Shearing (in.) 1.2 1.2 1.2 C (psf)Initial Degree of Saturation (%) 22.8 Ultimate 11 37.3 Final Moisture Content (%) 18.5 18.1 DIRECT SHEAR TEST RESULTS 150 N. Santa Anita Avenue Arcadia, CaliforniaConsolidated Drained ASTM D-3080 Checked by: PZ 18.1 March 2021 Figure B3 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Sh e a r S t r e s s ( k s f ) Normal Stress (ksf) Project No.: W1304-06-01 4.69 Boring No. B1 Normal Strest (kip/ft2) 1 3 5 Sample No. B1@20'Peak Shear Stress (kip/ft²) 1.17 3.03 0.05 Depth (ft) 20 Shear Stress @ End of Test (ksf) 1.01 2.63 4.05 Sample Type:Ring Deformation Rate (in./min.) 0.05 0.05 Soil Identification:Initial Sample Height (in.) 1.0 1.0 1.0 Light Brown Sand (SP)Ring Inside Diameter (in.) 2.375 2.375 2.375 Initial Moisture Content (%) 6.2 6.4 8.3 Strength Parameters Initial Dry Density (pcf) 96.8 95.0 100.3 22.4 32.8 Peak 318 41.4 Soil Height Before Shearing (in.) 1.2 1.2 1.2 C (psf)Initial Degree of Saturation (%) 22.5 Ultimate 280 37.3 Final Moisture Content (%) 22.6 17.1 DIRECT SHEAR TEST RESULTS 150 N. Santa Anita Avenue Arcadia, CaliforniaConsolidated Drained ASTM D-3080 Checked by: PZ 20.7 March 2021 Figure B4 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Sh e a r S t r e s s ( k s f ) Normal Stress (ksf) Project No.: W1304-06-01 5.03 Boring No. B1 Normal Strest (kip/ft2) 1 3 5 Sample No. B1@25'Peak Shear Stress (kip/ft²) 1.43 3.07 0.05 Depth (ft) 25 Shear Stress @ End of Test (ksf) 1.09 2.79 4.93 Sample Type:Ring Deformation Rate (in./min.) 0.05 0.05 Soil Identification:Initial Sample Height (in.) 1.0 1.0 1.0 Brown Sand (SP)Ring Inside Diameter (in.) 2.375 2.375 2.375 Initial Moisture Content (%) 8.7 0.0 11.1 Strength Parameters Initial Dry Density (pcf) 98.1 105.3 96.7 0.1 40.1 Peak 474 42.0 Soil Height Before Shearing (in.) 1.2 1.2 1.2 C (psf)Initial Degree of Saturation (%) 32.8 Ultimate 61 43.8 Final Moisture Content (%) 17.8 16.2 DIRECT SHEAR TEST RESULTS 150 N. Santa Anita Avenue Arcadia, CaliforniaConsolidated Drained ASTM D-3080 Checked by: PZ 15.5 March 2021 Figure B5 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Sh e a r S t r e s s ( k s f ) Normal Stress (ksf) Project No.: W1304-06-01 4.20 Boring No. B1 Normal Strest (kip/ft2) 1 3 5 Sample No. B1@30'Peak Shear Stress (kip/ft²) 1.37 3.01 0.05 Depth (ft) 30 Shear Stress @ End of Test (ksf) 0.91 2.88 3.60 Sample Type:Ring Deformation Rate (in./min.) 0.05 0.05 Soil Identification:Initial Sample Height (in.) 1.0 1.0 1.0 Brown Sand (SP)Ring Inside Diameter (in.) 2.375 2.375 2.375 Initial Moisture Content (%) 9.1 10.0 15.6 Strength Parameters Initial Dry Density (pcf) 98.7 104.2 92.1 43.5 50.8 Peak 650 35.3 Soil Height Before Shearing (in.) 1.2 1.2 1.2 C (psf)Initial Degree of Saturation (%) 34.8 Ultimate 250 34.0 Final Moisture Content (%) 19.8 18.5 DIRECT SHEAR TEST RESULTS 150 N. Santa Anita Avenue Arcadia, CaliforniaConsolidated Drained ASTM D-3080 Checked by: PZ 17.2 March 2021 Figure B6 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Sh e a r S t r e s s ( k s f ) Normal Stress (ksf) Project No.: W1304-06-01 4.35 Boring No. B1 Normal Strest (kip/ft2) 1 3 5 Sample No. B1@35'Peak Shear Stress (kip/ft²) 1.09 2.72 0.05 Depth (ft) 35 Shear Stress @ End of Test (ksf) 0.81 2.47 3.76 Sample Type:Ring Deformation Rate (in./min.) 0.05 0.05 Soil Identification:Initial Sample Height (in.) 1.0 1.0 1.0 Brown Sand (SW)Ring Inside Diameter (in.) 2.375 2.375 2.375 Initial Moisture Content (%) 8.0 7.6 11.2 Strength Parameters Initial Dry Density (pcf) 99.9 101.6 102.5 31.3 46.8 Peak 280 39.1 Soil Height Before Shearing (in.) 1.2 1.2 1.2 C (psf)Initial Degree of Saturation (%) 31.2 Ultimate 130 36.5 Final Moisture Content (%) 19.5 18.6 DIRECT SHEAR TEST RESULTS 150 N. Santa Anita Avenue Arcadia, CaliforniaConsolidated Drained ASTM D-3080 Checked by: PZ 17.5 March 2021 Figure B7 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Sh e a r S t r e s s ( k s f ) Normal Stress (ksf) Project No.: W1304-06-01 WATER ADDED AT 2.0 KSF SAMPLE ID. B3@10 SOIL TYPE DRY DENSITY (PCF) INITIAL MOISTURE (%) FINAL MOISTURE (%) Brown Sand (SP) 103.4 3.7 17.8 CONSOLIDATION TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California Checked by: PZ ASTM D-2435 March 2021 Figure B8 0 1 2 3 4 5 6 7 8 9 10 0.1 1.0 10.0 Pe r c e n t C o n s o l i d a t i o n Consolidation Pressure (ksf) Project No.: W1304-06-01 CONSOLIDATION TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California Checked by: PZ ASTM D-2435 March 2021 Figure B9 WATER ADDED AT 2.0 KSF SAMPLE ID. B4@12.5 SOIL TYPE DRY DENSITY (PCF) INITIAL MOISTURE (%) FINAL MOISTURE (%) Brown Sand (SP) 105.4 3.7 17.1 0 1 2 3 4 5 6 7 8 9 10 0.1 1.0 10.0 Pe r c e n t C o n s o l i d a t i o n Consolidation Pressure (ksf) Project No.: W1304-06-01 WATER ADDED AT 2.0 KSF SAMPLE ID. B3@15 SOIL TYPE DRY DENSITY (PCF) INITIAL MOISTURE (%) FINAL MOISTURE (%) Brown Sand (SP) 110.9 4.9 14.0 CONSOLIDATION TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California Checked by: PZ ASTM D-2435 March 2021 Figure B10 0 1 2 3 4 5 6 7 8 9 10 0.1 1.0 10.0 Pe r c e n t C o n s o l i d a t i o n Consolidation Pressure (ksf) Project No.: W1304-06-01 CONSOLIDATION TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California Checked by: PZ ASTM D-2435 March 2021 Figure B11 WATER ADDED AT 2.0 KSF SAMPLE ID. B4@17.5 SOIL TYPE DRY DENSITY (PCF) INITIAL MOISTURE (%) FINAL MOISTURE (%) Brown Sand (SP) 83.5 7.4 26.5 0 1 2 3 4 5 6 7 8 9 10 0.1 1.0 10.0 Pe r c e n t C o n s o l i d a t i o n Consolidation Pressure (ksf) Project No.: W1304-06-01 WATER ADDED AT 2.0 KSF SAMPLE ID. B3@20 SOIL TYPE DRY DENSITY (PCF) INITIAL MOISTURE (%) FINAL MOISTURE (%) Dark Brown Silty Sand (SM)118.1 14.0 15.0 CONSOLIDATION TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California Checked by: PZ ASTM D-2435 March 2021 Figure B12 0 1 2 3 4 5 6 7 8 9 10 0.1 1.0 10.0 Pe r c e n t C o n s o l i d a t i o n Consolidation Pressure (ksf) Project No.: W1304-06-01 WATER ADDED AT 2.0 KSF SAMPLE ID. B4@22.5 SOIL TYPE DRY DENSITY (PCF) INITIAL MOISTURE (%) FINAL MOISTURE (%) Reddish Brown Sand (SP)107.9 4.5 18.5 CONSOLIDATION TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California Checked by: PZ ASTM D-2435 March 2021 Figure B13 0 1 2 3 4 5 6 7 8 9 10 0.1 1.0 10.0 Pe r c e n t C o n s o l i d a t i o n Consolidation Pressure (ksf) Project No.: W1304-06-01 WATER ADDED AT 2.0 KSF SAMPLE ID. B2@25 SOIL TYPE DRY DENSITY (PCF) INITIAL MOISTURE (%) FINAL MOISTURE (%) Brown Sand (SP) 96.7 6.4 22.0 CONSOLIDATION TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California Checked by: PZ ASTM D-2435 March 2021 Figure B14 0 1 2 3 4 5 6 7 8 9 10 0.1 1.0 10.0 Pe r c e n t C o n s o l i d a t i o n Consolidation Pressure (ksf) Project No.: W1304-06-01 WATER ADDED AT 2.0 KSF SAMPLE ID. B1@27.5 SOIL TYPE DRY DENSITY (PCF) INITIAL MOISTURE (%) FINAL MOISTURE (%) BrownSand (SP) 117.7 5.3 12.7 CONSOLIDATION TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California Checked by: PZ ASTM D-2435 March 2021 Figure B15 0 1 2 3 4 5 6 7 8 9 10 0.1 1.0 10.0 Pe r c e n t C o n s o l i d a t i o n Consolidation Pressure (ksf) Project No.: W1304-06-01 WATER ADDED AT 2.0 KSF SAMPLE ID. B2@30 SOIL TYPE DRY DENSITY (PCF) INITIAL MOISTURE (%) FINAL MOISTURE (%) Light Brown Sand (SP)103.1 3.6 18.7 CONSOLIDATION TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California Checked by: PZ ASTM D-2435 March 2021 Figure B16 0 1 2 3 4 5 6 7 8 9 10 0.1 1.0 10.0 Pe r c e n t C o n s o l i d a t i o n Consolidation Pressure (ksf) Project No.: W1304-06-01 WATER ADDED AT 2.0 KSF SAMPLE ID. B1@32.5 SOIL TYPE DRY DENSITY (PCF) INITIAL MOISTURE (%) FINAL MOISTURE (%) Brown Sand (SP) 102.3 5.6 18.1 CONSOLIDATION TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California Checked by: PZ ASTM D-2435 March 2021 Figure B17 0 1 2 3 4 5 6 7 8 9 10 0.1 1.0 10.0 Pe r c e n t C o n s o l i d a t i o n Consolidation Pressure (ksf) Project No.: W1304-06-01 CONSOLIDATION TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California Checked by: PZ ASTM D-2435 March 2021 Figure B18 WATER ADDED AT 2.0 KSF SAMPLE ID. B2@35 SOIL TYPE DRY DENSITY (PCF) INITIAL MOISTURE (%) FINAL MOISTURE (%) Brown Sand (SW) 101.9 4.4 17.7 0 1 2 3 4 5 6 7 8 9 10 0.1 1.0 10.0 Pe r c e n t C o n s o l i d a t i o n Consolidation Pressure (ksf) Project No.: W1304-06-01 WATER ADDED AT 2.0 KSF SAMPLE ID. B1@40 SOIL TYPE DRY DENSITY (PCF) INITIAL MOISTURE (%) FINAL MOISTURE (%) Brown Sand (SW) 112.3 4.7 15.3 CONSOLIDATION TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California Checked by: PZ ASTM D-2435 March 2021 Figure B19 0 1 2 3 4 5 6 7 8 9 10 0.1 1.0 10.0 Pe r c e n t C o n s o l i d a t i o n Consolidation Pressure (ksf) Project No.: W1304-06-01 Sample No. SUMMARY OF LABORATORY WATER SOLUBLE SULFATE TEST RESULTS CALIFORNIA TEST NO. 417 Sample No.Water Soluble Sulfate (% SQ4)Sulfate Exposure* Chloride Ion Content (%) 0.002 0.004 SUMMARY OF LABORATORY CHLORIDE CONTENT TEST RESULTS EPA NO. 325.3 B3@5-10' B1@20-25' B3@5-10 0.000 S0 B1@20-25' 0.000 S0 SUMMARY OF LABORATORY POTENTIAL OF HYDROGEN (pH) AND RESISTIVITY TEST RESULTS CALIFORNIA TEST NO. 643 Sample No. B3@5-10' B1@20-25' pH 8.4 7.9 Resistivity (ohm centimeters) 21000 (Mildly Corrosive) 26000 (Mildly Corrosive) Checked by: PZ CORROSIVITY TEST RESULTS 150 N. Santa Anita Avenue Arcadia, California March 2021 Figure B20 Alexan Arcadia 52 December 2023 Appendix D: SWPPP Amendment Certifications Alexan Arcadia 53 December 2023 SWPPP Amendment No. Project Name: Alexan Arcadia Project Number: Qualified SWPPP Developer’s Certification of the Stormwater Pollution Prevention Plan Amendment “This Stormwater Pollution Prevention Plan and its appendices were prepared under my direction to meet the requirements of the California Construction General Permit (SWRCB Order No. 2009-009-DWQ as amended by 2010-0014-DWQ and 2012-0006-DWQ). I certify that I am a Qualified SWPPP Developer in good standing as of the date signed below.” QSD’s Signature Leah Isidro Date C78541 QSD Name PE, QSD QSD Certificate Number 661-705-4425 Title and Affiliation 27220 Turnberry Lane, Ste 190, Valencia CA 91355 Telephone Lisidro@psomas.com Address Email Alexan Arcadia 54 December 2023 Appendix E: Submitted Changes to PRDs Alexan Arcadia 55 December 2023 Log of Updated PRDs The General Permit allows for the reduction or increase of the total acreage covered under the General Permit when a portion of the project is complete and/or conditions for termination of coverage have been met; when ownership of a portion of the project is purchased by a different entity; or when new acreage is added to the project. Modified PRDs shall be filed electronically within 30 days of a reduction or increase in total disturbed area if a change in permit covered acreage is to be sought. The SWPPP shall be modified appropriately, with revisions and amendments recorded in Appendix C. Updated PRDs submitted electronically via SMARTS can be found in this Appendix. This appendix includes all of the following updated PRDs (check all that apply): Revised Notice of Intent (NOI); Revised Site Map; Revised Risk Assessment; New landowner’s information (name, address, phone number, email address); and New signed certification statement. Trammell Crow Residential Legally Responsible Person Signature of Legally Responsible Person or Approved Signatory Date Todd Phillips (760) 431 3366 Name of Legally Responsible Person or Approved Signatory Telephone Number Alexan Arcadia 56 December 2023 Appendix F: Construction Schedule Alexan Arcadia 57 December 2023 Appendix G: Construction Activities, Materials Used, and Associated Pollutants Alexan Arcadia 58 December 2023 General Work Activity/ Products With Potential Stormwater Pollutants Specific Work Activity/Products With Potential Stormwater Pollutants Pollutant Categories Concrete / Masonry Cement and brick dust Concrete curing compounds Metals, Synthetic Organics Liquid waste · Wash waters · Irrigation line testing/flushing Metals, Synthetic Organics Painting · Paint thinners, acetone, methyl ethyl ketone, stripper paints, lacquers, varnish, enamels, turpentine, gum spirit, solvents, dyes, stripping pigments and sanding Metals, Synthetic Organics Planting / Vegetation Management · Vegetation control (pesticides/herbicides) · Planting · Plant maintenance · Vegetation removal Nutrients, Metals, Synthetic Organics Soil preparation/amendments · Use of soil additives/amendments Nutrients Solid waste · Litter, trash and debris · Vegetation Gross Pollutants Utility line testing and flushing · Hydrostatic test water · Pipe flushing Synthetic Organics Vehicle and equipment use · Equipment operation · Equipment maintenance · Equipment washing · Equipment fueling Oil and Grease Alexan Arcadia 59 December 2023 Table G.1 Construction Activities and Associated Pollutants Phase Activity Associated Materials or Pollutants Pollutant Category(1) Gr a d i n g a n d L a n d De v e l o p m e n t Demolition Building rubble, concrete, paint, asphalt, sediment Sediment, Metals, Oil & Grease Vehicle and Equipment Use -Equipment Operation -Equipment maintenance -Equipment Washing -Equipment fueling Oil & Grease Solid Waste Litter, trash, debris Gross Pollutants Asphalt Paving, Curbs Hot and Cold Mix Asphalt Oil and Grease Sanitary Waste Portable Toilets Nutrients, Bacteria St r e e t s a n d U t i l i t i e s Ph a s e Asphalt Paving, Curbs Hot and Cold Mix Asphalt Oil and Grease Utility Line testing and Flushing Hydrostatic Test Water Pipe Flushing Synthetic Organics Sanitary Waste Disturbance of existing sewer lines Nutrients, Bacteria Liquid Waste Wash waters Irrigation line testing/flushing Metals, Synthetic Organics Ve r t i c a l Co n s t r u c t i o n Ph a s e N/A La n d s c a p i n g a n d S i t e St a b i l i z a t i o n P h a s e Planting/ Vegetation Management Vegetation Control Planting Plant Maintenance Vegetation Removal Nutrients, Metal, Synthetic Organics Soil Preparation/Amendments Use of soil additives/amendments Nutrients (1) Categories per CASQA BMP Handbook (i.e., Sediment, Nutrients, Bacteria and Viruses, Oil and Grease, Metals, Synthetic Organics, Pesticides, Gross Pollutants, and Vector Production) Alexan Arcadia 60 December 2023 Appendix H: CASQA Stormwater BMP Handbook Portal: Construction Fact Sheets Scheduling EC-1 November 2009 California Stormwater BMP Handbook 1 of 3 Construction www.casqa.org Description and Purpose Scheduling is the development of a written plan that includes sequencing of construction activities and the implementation of BMPs such as erosion control and sediment control while taking local climate (rainfall, wind, etc.) into consideration. The purpose is to reduce the amount and duration of soil exposed to erosion by wind, rain, runoff, and vehicle tracking, and to perform the construction activities and control practices in accordance with the planned schedule. Suitable Applications Proper sequencing of construction activities to reduce erosion potential should be incorporated into the schedule of every construction project especially during rainy season. Use of other, more costly yet less effective, erosion and sediment control BMPs may often be reduced through proper construction sequencing. Limitations Environmental constraints such as nesting season prohibitions reduce the full capabilities of this BMP. Implementation Avoid rainy periods. Schedule major grading operations during dry months when practical. Allow enough time before rainfall begins to stabilize the soil with vegetation or physical means or to install sediment trapping devices. Plan the project and develop a schedule showing each phase of construction. Clearly show how the rainy season relates Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Scheduling EC-1 November 2009 California Stormwater BMP Handbook 2 of 3 Construction www.casqa.org to soil disturbing and re-stabilization activities. Incorporate the construction schedule into the SWPPP. Include on the schedule, details on the rainy season implementation and deployment of: -Erosion control BMPs -Sediment control BMPs -Tracking control BMPs -Wind erosion control BMPs -Non-stormwater BMPs -Waste management and materials pollution control BMPs Include dates for activities that may require non-stormwater discharges such as dewatering, sawcutting, grinding, drilling, boring, crushing, blasting, painting, hydro-demolition, mortar mixing, pavement cleaning, etc. Work out the sequencing and timetable for the start and completion of each item such as site clearing and grubbing, grading, excavation, paving, foundation pouring utilities installation, etc., to minimize the active construction area during the rainy season. -Sequence trenching activities so that most open portions are closed before new trenching begins. -Incorporate staged seeding and re-vegetation of graded slopes as work progresses. -Schedule establishment of permanent vegetation during appropriate planting time for specified vegetation. Non-active areas should be stabilized as soon as practical after the cessation of soil disturbing activities or one day prior to the onset of precipitation. Monitor the weather forecast for rainfall. When rainfall is predicted, adjust the construction schedule to allow the implementation of soil stabilization and sediment treatment controls on all disturbed areas prior to the onset of rain. Be prepared year round to deploy erosion control and sediment control BMPs. Erosion may be caused during dry seasons by un-seasonal rainfall, wind, and vehicle tracking. Keep the site stabilized year round, and retain and maintain rainy season sediment trapping devices in operational condition. Apply permanent erosion control to areas deemed substantially complete during the project’s defined seeding window. Costs Construction scheduling to reduce erosion may increase other construction costs due to reduced economies of scale in performing site grading. The cost effectiveness of scheduling techniques should be compared with the other less effective erosion and sedimentation controls to achieve a cost effective balance. Scheduling EC-1 November 2009 California Stormwater BMP Handbook 3 of 3 Construction www.casqa.org Inspection and Maintenance Verify that work is progressing in accordance with the schedule. If progress deviates, take corrective actions. Amend the schedule when changes are warranted. Amend the schedule prior to the rainy season to show updated information on the deployment and implementation of construction site BMPs. References Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Stormwater Management for Construction Activities Developing Pollution Prevention Plans and Best Management Practices (EPA 832-R-92-005), U.S. Environmental Protection Agency, Office of Water, September 1992. Preservation Of Existing Vegetation EC-2 November 2009 California Stormwater BMP Handbook 1 of 4 Construction www.casqa.org Description and Purpose Carefully planned preservation of existing vegetation minimizes the potential of removing or injuring existing trees, vines, shrubs, and grasses that protect soil from erosion. Suitable Applications Preservation of existing vegetation is suitable for use on most projects. Large project sites often provide the greatest opportunity for use of this BMP. Suitable applications include the following: Areas within the site where no construction activity occurs, or occurs at a later date. This BMP is especially suitable to multi year projects where grading can be phased. Areas where natural vegetation exists and is designated for preservation. Such areas often include steep slopes, watercourse, and building sites in wooded areas. Areas where local, state, and federal government require preservation, such as vernal pools, wetlands, marshes, certain oak trees, etc. These areas are usually designated on the plans, or in the specifications, permits, or environmental documents. Where vegetation designated for ultimate removal can be temporarily preserved and be utilized for erosion control and sediment control. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Preservation Of Existing Vegetation EC-2 November 2009 California Stormwater BMP Handbook 2 of 4 Construction www.casqa.org Limitations Requires forward planning by the owner/developer, contractor, and design staff. Limited opportunities for use when project plans do not incorporate existing vegetation into the site design. For sites with diverse topography, it is often difficult and expensive to save existing trees while grading the site satisfactory for the planned development. Implementation The best way to prevent erosion is to not disturb the land. In order to reduce the impacts of new development and redevelopment, projects may be designed to avoid disturbing land in sensitive areas of the site (e.g., natural watercourses, steep slopes), and to incorporate unique or desirable existing vegetation into the site’s landscaping plan. Clearly marking and leaving a buffer area around these unique areas during construction will help to preserve these areas as well as take advantage of natural erosion prevention and sediment trapping. Existing vegetation to be preserved on the site must be protected from mechanical and other injury while the land is being developed. The purpose of protecting existing vegetation is to ensure the survival of desirable vegetation for shade, beautification, and erosion control. Mature vegetation has extensive root systems that help to hold soil in place, thus reducing erosion. In addition, vegetation helps keep soil from drying rapidly and becoming susceptible to erosion. To effectively save existing vegetation, no disturbances of any kind should be allowed within a defined area around the vegetation. For trees, no construction activity should occur within the drip line of the tree. Timing Provide for preservation of existing vegetation prior to the commencement of clearing and grubbing operations or other soil disturbing activities in areas where no construction activity is planned or will occur at a later date. Design and Layout Mark areas to be preserved with temporary fencing. Include sufficient setback to protect roots. Orange colored plastic mesh fencing works well. Use appropriate fence posts and adequate post spacing and depth to completely support the fence in an upright position. Locate temporary roadways, stockpiles, and layout areas to avoid stands of trees, shrubs, and grass. Consider the impact of grade changes to existing vegetation and the root zone. Maintain existing irrigation systems where feasible. Temporary irrigation may be required. Instruct employees and subcontractors to honor protective devices. Prohibit heavy equipment, vehicular traffic, or storage of construction materials within the protected area. Preservation Of Existing Vegetation EC-2 November 2009 California Stormwater BMP Handbook 3 of 4 Construction www.casqa.org Costs There is little cost associated with preserving existing vegetation if properly planned during the project design, and these costs may be offset by aesthetic benefits that enhance property values. During construction, the cost for preserving existing vegetation will likely be less than the cost of applying erosion and sediment controls to the disturbed area. Replacing vegetation inadvertently destroyed during construction can be extremely expensive, sometimes in excess of $10,000 per tree. Inspection and Maintenance During construction, the limits of disturbance should remain clearly marked at all times. Irrigation or maintenance of existing vegetation should be described in the landscaping plan. If damage to protected trees still occurs, maintenance guidelines described below should be followed: Verify that protective measures remain in place. Restore damaged protection measures immediately. Serious tree injuries shall be attended to by an arborist. Damage to the crown, trunk, or root system of a retained tree shall be repaired immediately. Trench as far from tree trunks as possible, usually outside of the tree drip line or canopy. Curve trenches around trees to avoid large roots or root concentrations. If roots are encountered, consider tunneling under them. When trenching or tunneling near or under trees to be retained, place tunnels at least 18 in. below the ground surface, and not below the tree center to minimize impact on the roots. Do not leave tree roots exposed to air. Cover exposed roots with soil as soon as possible. If soil covering is not practical, protect exposed roots with wet burlap or peat moss until the tunnel or trench is ready for backfill. Cleanly remove the ends of damaged roots with a smooth cut. Fill trenches and tunnels as soon as possible. Careful filling and tamping will eliminate air spaces in the soil, which can damage roots. If bark damage occurs, cut back all loosened bark into the undamaged area, with the cut tapered at the top and bottom and drainage provided at the base of the wood. Limit cutting the undamaged area as much as possible. Aerate soil that has been compacted over a trees root zone by punching holes 12 in. deep with an iron bar, and moving the bar back and forth until the soil is loosened. Place holes 18 in. apart throughout the area of compacted soil under the tree crown. Fertilization Fertilize stressed or damaged broadleaf trees to aid recovery. Fertilize trees in the late fall or early spring. Preservation Of Existing Vegetation EC-2 November 2009 California Stormwater BMP Handbook 4 of 4 Construction www.casqa.org -Apply fertilizer to the soil over the feeder roots and in accordance with label instructions, but never closer than 3 ft to the trunk. Increase the fertilized area by one-fourth of the crown area for conifers that have extended root systems. Retain protective measures until all other construction activity is complete to avoid damage during site cleanup and stabilization. References County of Sacramento Tree Preservation Ordinance, September 1981. Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Stormwater Management of the Puget Sound Basin, Technical Manual, Publication #91-75, Washington State Department of Ecology, February 1992. Water Quality Management Plan for The Lake Tahoe Region, Volume II, Handbook of Management Practices, Tahoe Regional Planning Agency, November 1988. Hydraulic Mulch EC-3 July 2012 California Stormwater BMP Handbook 1 of 5 Construction www.casqa.org Description and Purpose Hydraulic Mulch consists of various types of fibrous materials mixed with water and sprayed onto the soil surface in slurry form to provide a layer of temporary protection from wind and water erosion. Suitable Applications Hydraulic mulch as a temporary, stand alone, erosion control BMP is suitable for disturbed areas that require temporary protection from wind and water erosion until permanent soil stabilization activities commence. Examples include: Rough-graded areas that will remain inactive for longer than permit-required thresholds (e.g., 14 days) or otherwise require stabilization to minimize erosion or prevent sediment discharges. Soil stockpiles. Slopes with exposed soil between existing vegetation such as trees or shrubs. Slopes planted with live, container-grown vegetation or plugs. Slopes burned by wildfire. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Category Secondary Category Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives EC-4 Hydroseeding EC-5 Soil Binders EC-6 Straw Mulch EC-7 Geotextiles and Mats EC-8 Wood Mulching EC-14 Compost Blanket EC-16 Non-Vegetative Stabilization If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Hydraulic Mulch EC-3 July 2012 California Stormwater BMP Handbook 2 of 5 Construction www.casqa.org Hydraulic mulch can also be applied to augment other erosion control BMPs such as: In conjunction with straw mulch (see EC-6 Straw Mulch) where the rate of hydraulic mulch is reduced to 100-500 lbs per acre and the slurry is applied over the straw as a tackifying agent to hold the straw in place. Supplemental application of soil amendments, such as fertilizer, lime, gypsum, soil bio- stimulants or compost. Limitations In general,hydraulic mulch is not limited by slope length, gradient or soil type.However, the following limitations typically apply: Most hydraulic mulch applications, particularly bonded fiber matrices (BFMs),require at least 24 hours to dry before rainfall occurs. Temporary applications (i.e., without a vegetative component) may require a second application in order to remain effective for an entire rainy season. Treatment areas must be accessible to hydraulic mulching equipment. Availability of water sources in remote areas for mixing and application. As a stand-alone temporary BMP, hydraulic mulches may need to be re-applied to maintain their erosion control effectiveness, typically after 6-12 months depending on the type of mulch used. Availability of hydraulic mulching equipment may be limited just prior to the rainy season and prior to storms due to high demand. Cellulose fiber mulches alone may not perform well on steep slopes or in course soils. This BMP consists of a mixture of several constituents (e.g., fibers/mulches, tackifiers, and other chemical constituents), some of which may be proprietary and may come pre-mixed by the manufacturer.The water quality impacts of these constituents are relatively unknown and some may have water quality impacts due to their chemical makeup.Refer to specific chemical properties identified in the product Material Safety Data Sheet; products should be evaluated for project-specific implementation by the SWPPP Preparer.Refer to factsheet EC-05 for further guidance on selecting soil binders. Implementation Where feasible,it is preferable to prepare soil surfaces prior to application by roughening embankments and fill areas with a crimping or punching type roller or by track walking. The majority of hydraulic mulch applications do not necessarily require surface/soil preparation (See EC-15 Soil Preparation) although in almost every case where re-vegetation is included as part of the practice, soil preparation can be beneficial.One of the advantages of hydraulic mulch over other erosion control methods is that it can be applied in areas where soil preparation is precluded by site conditions, such as steep slopes, rocky soils, or inaccessibility. Hydraulic Mulch EC-3 July 2012 California Stormwater BMP Handbook 3 of 5 Construction www.casqa.org Avoid mulch over spray onto roads, sidewalks, drainage channels, existing vegetation, etc. Hydraulic mulching is generally performed utilizing specialized machines that have a large water-holding/mixing tank and some form of mechanical agitation or other recirculation method to keep water, mulch and soil amendments in suspension. The mixed hydraulic slurry can be applied from a tower sprayer on top of the machine or by extending a hose to areas remote from the machine. Where possible apply hydraulic mulch from multiple directions to adequately cover the soil. Application from a single direction can result in shadowing, uneven coverage and failure of the BMP. Hydraulic mulch can also include a vegetative component, such as seed, rhizomes,or stolons (see EC-4 Hydraulic Seed). Typical hydraulic mulch application rates range from 2,000 pounds per acre for standard mulches (SMs) to 3,500 pounds per acre for BFMs. However, the required amount of hydraulic mulch to provide adequate coverage of exposed topsoil may appear to exceed the standard rates when the roughness of the soil surface is changed due to soil preparation methods (see EC-15 Soil Preparation) or by slope gradient. Other factors such as existing soil moisture and soil texture can have a profound effect on the amount of hydraulic mulch required (i.e. application rate) applied to achieve an erosion- resistant covering. Avoid use of mulch without a tackifier component, especially on slopes. Mulches used in the hydraulic mulch slurry can include: -Cellulose fiber -Thermally-processed wood fibers -Cotton -Synthetics -Compost (see EC-14, Compost Blanket) Additional guidance on the comparison and selection of temporary slope stabilization methods is provided in Appendix F of the Handbook. Categories of Hydraulic Mulches Standard Hydraulic Mulch (SM) Standard hydraulic mulches are generally applied at a rate of 2,000 pounds per acre and are manufactured containing around 5% tackifier (i.e. soil binder), usually a plant-derived guar or psyllium type. Most standard mulches are green in color derived from food-color based dyes. Hydraulic Mulch EC-3 July 2012 California Stormwater BMP Handbook 4 of 5 Construction www.casqa.org Hydraulic Matrices (HM) and Stabilized Fiber Matrices (SFM) Hydraulic matrices and stabilized fiber matrices are slurries which contain increased levels of tackifiers/soil binders; usually 10% or more by weight. HMs and SFMs have improved performance compared to a standard hydraulic mulch (SM) because of the additional percentage of tackifier and because of their higher application rates, typically 2,500 –4,000 pounds per acre. Hydraulic matrices can include a mixture of fibers, for example, a 50/50 blend of paper and wood fiber. In the case of an SFM, the tackifier/soil binder is specified as a polyacrylamide (PAM). Bonded Fiber Matrix (BFM) Bonded fiber matrices (BFMs) are hydraulically-applied systems of fibers, adhesives (typically guar based) and chemical cross-links. Upon drying,the slurry forms an erosion-resistant blanket that prevents soil erosion and promotes vegetation establishment. The cross-linked adhesive in the BFM should be biodegradable and should not dissolve or disperse upon re- wetting. BFMs are typically applied at rates from 3,000 to 4,000 lbs/acre based on the manufacturer’s recommendation. BFMs should not be applied immediately before, during or immediately after rainfall or if the soil is saturated. Depending on the product, BFMs typically require 12 to 24 hours to dry and become effective. Mechanically-Bonded Fiber Matrices (MBFM) Mechanically-bonded fiber matrices (MBFMs)are hydraulically applied systems similar to BFM that use crimped synthetic fibers and PAM and are typically applied to a slope at a higher application rate than a standard BFM. Hydraulic Compost Matrix (HCM) Hydraulic compost matrix (HCM) is a field-derived practice whereby finely graded or sifted compost is introduced into the hydraulic mulch slurry. A guar-type tackifier can be added for steeper slope applications as well as any specified seed mixtures. A HCM can help to accelerate seed germination and growth. HCMs are particularly useful as an in-fill for three-dimensional re-vegetation geocomposites, such as turf reinforcement mats (TRM)(see EC-7 Geotextiles and Mats). Costs Average installed costs for hydraulic mulch categories are is provided in Table 1, below. Table 1 HYDRAULIC MULCH BMPs INSTALLED COSTS BMP Installed Cost/Acre Standard Hydraulic Mulching (SM)$1,700 -$3,600 per acre Hydraulic Matrices (HM)and Stabilized Fiber Matrices Guar-based PAM-based $2,000 -$4,000 per acre $2,500 -$5,610 per acre Bonded Fiber Matrix (BFM)$3,900 -$6,900 per acre Mechanically Bonded Fiber Matrix (MBFM)$4,500 -$6,000 per acre Hydraulic Compost Matrix (HCM)$3,000 -$3,500 per acre Hydraulic Mulch EC-3 July 2012 California Stormwater BMP Handbook 5 of 5 Construction www.casqa.org Source: Cost information received from individual product manufacturers solicited by Geosyntec Consultants (2004) Inspection and Maintenance Maintain an unbroken, temporary mulched ground cover throughout the period of construction when the soils are not being reworked. BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Areas where erosion is evident should be repaired and BMPs re-applied as soon as possible. Care should be exercised to minimize the damage to protected areas while making repairs, as any area damaged will require re-application of BMPs. Compare the number of bags or weight of applied mulch to the area treated to determine actual application rates and compliance with specifications. References Soil Stabilization BMP Research for Erosion and Sediment Controls: Cost Survey Technical Memorandum, State of California Department of Transportation (Caltrans), July 2007. Controlling Erosion of Construction Sites,Agricultural Information #347, U.S. Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS) (formerly Soil Conservation Service –SCS). Guides for Erosion and Sediment Control in California, USDA Soils Conservation Service, January 1991. Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995. Sedimentation and Erosion Control, An Inventory of Current Practices Draft, US EPA, April 1990. Soil Erosion by Water, Agriculture Information Bulletin #513, U.S. Department of Agriculture, Soil Conservation Service. Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003. Guidance Document: Soil Stabilization for Temporary Slopes, State of California Department of Transportation (Caltrans), November 1999 Stormwater Management of the Puget Sound Basin, Technical Manual, Publication #91-75, Washington State Department of Ecology, February 1992. Water Quality Management Plan for the Lake Tahoe Region, Volume II, Handbook of Management Practices, Tahoe Regional Planning Agency, November 1988. Silt Fence SE-1 July 2012 California Stormwater BMP Handbook Portal 1 of 9 Construction www.casqa.org Description and Purpose A silt fence is made of a woven geotextile that has been entrenched, attached to supporting poles, and sometimes backed by a plastic or wire mesh for support. The silt fence detains water, promoting sedimentation of coarse sediment behind the fence. Silt fence does not retain soil fine particles like clays or silts. Suitable Applications Silt fences are suitable for perimeter control, placed below areas where sheet flows discharge from the site. They could also be used as interior controls below disturbed areas where runoff may occur in the form of sheet and rill erosion and around inlets within disturbed areas (SE-10). Silt fences should not be used in locations where the flow is concentrated. Silt fences should always be used in combination with erosion controls. Suitable applications include: At perimeter of a project. Below the toe or down slope of exposed and erodible slopes. Along streams and channels. Around temporary spoil areas and stockpiles. Around inlets. Below other small cleared areas. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Category Secondary Category Targeted Constituents Sediment (coarse sediment) Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives SE-5 Fiber Rolls SE-6 Gravel Bag Berm SE-12 Manufactured Linear Sediment Controls SE-13 Compost Socks and Berms SE-14 Biofilter Bags If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Silt Fence SE-1 July 2012 California Stormwater BMP Handbook Portal 2 of 9 Construction www.casqa.org Limitations Do not use in streams, channels, drain inlets, or anywhere flow is concentrated. Do not use in locations where ponded water may cause a flooding hazard. Do not use silt fence to divert water flows or place across any contour line. Improperly installed fences are subject to failure from undercutting, overtopping, or collapsing. Must be trenched and keyed in. Not intended for use as a substitute for Fiber Rolls (SE-5), when fiber rolls are being used as a slope interruption device. Do not use on slopes subject to creeping, slumping, or landslides. Implementation General A silt fence is a temporary sediment barrier consisting of woven geotextile stretched across and attached to supporting posts, trenched-in, and, depending upon the strength of fabric used, supported with plastic or wire mesh fence. Silt fences trap coarse sediment by intercepting and detaining sediment-laden runoff from disturbed areas in order to promote sedimentation behind the fence. The following layout and installation guidance can improve performance and should be followed: Silt fence should be used in combination with erosion controls up-slope in order to provide the most effective sediment control. Silt fence alone is not effective at reducing turbidity. (Barrett and Malina, 2004) Designers should consider diverting sediment laden water to a temporary sediment basin or trap. (EPA, 2012) Use principally in areas where sheet flow occurs. Install along a level contour, so water does not pond more than 1.5 ft at any point along the silt fence. Provide sufficient room for runoff to pond behind the fence and to allow sediment removal equipment to pass between the silt fence and toes of slopes or other obstructions. About 1200 ft2 of ponding area should be provided for every acre draining to the fence. Efficiency of silt fences is primarily dependent on the detention time of the runoff behind the control. (Barrett and Malina, 2004) The drainage area above any fence should not exceed a quarter of an acre. (Rule of Thumb- 100-feet of silt fence per 10,000 square feet of disturbed area.) (EPA 2012) Silt Fence SE-1 July 2012 California Stormwater BMP Handbook Portal 3 of 9 Construction www.casqa.org The maximum length of slope draining to any point along the silt fence should be 100 ft per foot of silt fence. Turn the ends of the filter fence uphill to prevent stormwater from flowing around the fence. Leave an undisturbed or stabilized area immediately down slope from the fence where feasible. Silt fences should remain in place until the disturbed area draining to the silt fence is permanently stabilized, after which, the silt fence fabric and posts should be removed and properly disposed. J-Hooks, which have ends turning up the slope to break up long runs of fence and provide multiple storage areas that work like mini-retention areas, may be used to increase the effectiveness of silt fence. Be aware of local regulations regarding the type and installation requirements of silt fence, which may differ from those presented in this fact sheet. Design and Layout In areas where high winds are anticipated the fence should be supported by a plastic or wire mesh. The geotextile fabric of the silt fence should contain ultraviolet inhibitors and stabilizers to provide longevity equivalent to the project life or replacement schedule. Layout in accordance with the attached figures. For slopes that contain a high number of rocks or large dirt clods that tend to dislodge, it may be necessary to protect silt fence from rocks (e.g., rockfall netting) ensure the integrity of the silt fence installation. Standard vs. Heavy Duty Silt Fence Standard Silt Fence Generally applicable in cases where the area draining to fence produces moderate sediment loads. Heavy Duty Silt Fence Heavy duty silt fence usually has 1 or more of the following characteristics, not possessed by standard silt fence. o Fabric is reinforced with wire backing or additional support. o Posts are spaced closer than pre-manufactured, standard silt fence products. Use is generally limited to areas affected by high winds. Area draining to fence produces moderate sediment loads. Materials Standard Silt Fence Silt fence material should be woven geotextile with a minimum width of 36 in. The fabric should conform to the requirements in ASTM designation D6461. Wooden stakes should be commercial quality lumber of the size and shape shown on the plans. Each stake should be free from decay, splits or cracks longer than the Silt Fence SE-1 July 2012 California Stormwater BMP Handbook Portal 4 of 9 Construction www.casqa.org thickness of the stake or other defects that would weaken the stakes and cause the stakes to be structurally unsuitable. Staples used to fasten the fence fabric to the stakes should be not less than 1.75 in. long and should be fabricated from 15 gauge or heavier wire. The wire used to fasten the tops of the stakes together when joining two sections of fence should be 9 gauge or heavier wire. Galvanizing of the fastening wire will not be required. Heavy-Duty Silt Fence Some silt fence has a wire backing to provide additional support, and there are products that may use prefabricated plastic holders for the silt fence and use metal posts instead of wood stakes. Installation Guidelines Traditional Method Silt fences are to be constructed on a level contour. Sufficient area should exist behind the fence for ponding to occur without flooding or overtopping the fence. A trench should be excavated approximately 6 in. wide and 6 in. deep along the line of the proposed silt fence (trenches should not be excavated wider or deeper than necessary for proper silt fence installation). Bottom of the silt fence should be keyed-in a minimum of 12 in. Posts should be spaced a maximum of 6 ft apart and driven securely into the ground a minimum of 18 in. or 12 in. below the bottom of the trench. When standard strength geotextile is used, a plastic or wire mesh support fence should be fastened securely to the upslope side of posts using heavy duty wire staples at least 1 in. long. The mesh should extend into the trench. When extra-strength geotextile and closer post spacing are used, the mesh support fence may be eliminated. Woven geotextile should be purchased in a long roll, then cut to the length of the barrier. When joints are necessary, geotextile should be spliced together only at a support post, with a minimum 6 in. overlap and both ends securely fastened to the post. The trench should be backfilled with native material and compacted. Construct the length of each reach so that the change in base elevation along the reach does not exceed 1/3 the height of the barrier; in no case should the reach exceed 500 ft. Cross barriers should be a minimum of 1/3 and a maximum of ½ the height of the linear barrier. See typical installation details at the end of this fact sheet. Silt Fence SE-1 July 2012 California Stormwater BMP Handbook Portal 5 of 9 Construction www.casqa.org Installation Guidelines - Static Slicing Method Static Slicing is defined as insertion of a narrow blade pulled behind a tractor, similar to a plow blade, at least 10 inches into the soil while at the same time pulling silt geotextile fabric into the ground through the opening created by the blade to the depth of the blade. Once the geotextile is installed, the soil is compacted using tractor tires. This method will not work with pre-fabricated, wire backed silt fence. Benefits: o Ease of installation (most often done with a 2 person crew). o Minimal soil disturbance. o Better level of compaction along fence, less susceptible to undercutting o Uniform installation. Limitations: o Does not work in shallow or rocky soils. o Complete removal of geotextile material after use is difficult. o Be cautious when digging near potential underground utilities. Costs It should be noted that costs vary greatly across regions due to available supplies and labor costs. Average annual cost for installation using the traditional silt fence installation method (assumes 6 month useful life) is $7 per linear foot based on vendor research. Range of cost is $3.50 - $9.10 per linear foot. Inspection and Maintenance BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Repair undercut silt fences. Repair or replace split, torn, slumping, or weathered fabric. The lifespan of silt fence fabric is generally 5 to 8 months. Silt fences that are damaged and become unsuitable for the intended purpose should be removed from the site of work, disposed, and replaced with new silt fence barriers. Sediment that accumulates in the BMP should be periodically removed in order to maintain BMP effectiveness. Sediment should be removed when the sediment accumulation reaches 1/3 of the barrier height. Silt fences should be left in place until the upgradient area is permanently stabilized. Until then, the silt fence should be inspected and maintained regularly. Silt Fence SE-1 July 2012 California Stormwater BMP Handbook Portal 6 of 9 Construction www.casqa.org Remove silt fence when upgradient areas are stabilized. Fill and compact post holes and anchor trench, remove sediment accumulation, grade fence alignment to blend with adjacent ground, and stabilize disturbed area. References Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995. Monitoring Data on Effectiveness of Sediment Control Techniques, Proceedings of World Water and Environmental Resources Congress, Barrett M. and Malina J. 2004. National Management Measures to Control Nonpoint Source Pollution from Urban Areas, United States Environmental Protection Agency, 2002. Proposed Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters, Work Group-Working Paper, USEPA, April 1992. Sedimentation and Erosion Control Practices, and Inventory of Current Practices (Draft), USEPA, 1990. Southeastern Wisconsin Regional Planning Commission (SWRPC). Costs of Urban Nonpoint Source Water Pollution Control Measures. Technical Report No. 31. Southeastern Wisconsin Regional Planning Commission, Waukesha, WI. 1991. Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003. Stormwater Management Manual for The Puget Sound Basin, Washington State Department of Ecology, Public Review Draft, 1991. U.S. Environmental Protection Agency (USEPA). Stormwater Best Management Practices: Silt Fences. U.S. Environmental Protection Agency, Office of Water, Washington, DC, 2012. U.S. Environmental Protection Agency (USEPA). Stormwater Management for Industrial Activities: Developing Pollution Prevention Plans and Best Management Practices. U.S. Environmental Protection Agency, Office of Water, Washington, DC, 1992. Water Quality Management Plan for the Lake Tahoe Region, Volume II, Handbook of Management Practices, Tahoe Regional Planning Agency, November 1988. Soil Stabilization BMP Research for Erosion and Sediment Controls: Cost Survey Technical Memorandum, State of California Department of Transportation (Caltrans), July 2007. Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005. Silt Fence SE-1 July 2012 California Stormwater BMP Handbook Portal 7 of 9 Construction www.casqa.org Silt Fence SE-1 July 2012 California Stormwater BMP Handbook Portal 8 of 9 Construction www.casqa.org Silt Fence SE-1 July 2012 California Stormwater BMP Handbook Portal 9 of 9 Construction www.casqa.org Check Dams SE-4 July 2012 California Stormwater BMP Handbook Portal 1 of 7 Construction www.casqa.org Description and Purpose A check dam is a small barrier constructed of rock, gravel bags, sandbags, fiber rolls, or other proprietary products, placed across a constructed swale or drainage ditch. Check dams reduce the effective slope of the channel, thereby reducing scour and channel erosion by reducing flow velocity and increasing residence time within the channel, allowing sediment to settle. Suitable Applications Check dams may be appropriate in the following situations: To promote sedimentation behind the dam. To prevent erosion by reducing the velocity of channel flow in small intermittent channels and temporary swales. In small open channels that drain 10 acres or less. In steep channels where stormwater runoff velocities exceed 5 ft/s. During the establishment of grass linings in drainage ditches or channels. In temporary ditches where the short length of service does not warrant establishment of erosion-resistant linings. To act as a grade control structure. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Category Secondary Category Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives SE-5 Fiber Rolls SE-6 Gravel Bag Berm SE-8 Sandbag Barrier SE-12 Manufactured Linear Sediment Controls SE-14 Biofilter Bags If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Check Dams SE-4 July 2012 California Stormwater BMP Handbook Portal 2 of 7 Construction www.casqa.org Limitations Not to be used in live streams or in channels with extended base flows. Not appropriate in channels that drain areas greater than 10 acres. Not appropriate in channels that are already grass-lined unless erosion potential or sediment-laden flow is expected, as installation may damage vegetation. Require extensive maintenance following high velocity flows. Promotes sediment trapping which can be re-suspended during subsequent storms or removal of the check dam. Do not construct check dams with straw bales or silt fence. Water suitable for mosquito production may stand behind check dams, particularly if subjected to daily non-stormwater discharges. Implementation General Check dams reduce the effective slope and create small pools in swales and ditches that drain 10 acres or less. Using check dams to reduce channel slope reduces the velocity of stormwater flows, thus reducing erosion of the swale or ditch and promoting sedimentation. Thus, check dams are dual-purpose and serve an important role as erosion controls as well as as sediment controls. Note that use of 1-2 isolated check dams for sedimentation will likely result in little net removal of sediment because of the small detention time and probable scour during longer storms. Using a series of check dams will generally increase their effectiveness. A sediment trap (SE-3) may be placed immediately upstream of the check dam to increase sediment removal efficiency. Design and Layout Check dams work by decreasing the effective slope in ditches and swales. An important consequence of the reduced slope is a reduction in capacity of the ditch or swale. This reduction in capacity should be considered when using this BMP, as reduced capacity can result in overtopping of the ditch or swale and resultant consequences. In some cases, such as a construction flows, the ditch or swale may have sufficient capacity such that the temporary reduction in capacity due to check dams is acceptable. When check dams reduce capacities beyond acceptable limits, either: e BMPs, or. Increase the size of the ditch or swale to restore capacity. Maximum slope and velocity reduction is achieved when the toe of the upstream dam is at the same elevation as the top of the downstream dam pacing Between Check the end of this fact sheet). The center section of the dam should be lower than the edge sections (at least 6 inches), acting as a spillway, so that the check dam will direct flows to the center of Check Dams SE-4 July 2012 California Stormwater BMP Handbook Portal 3 of 7 Construction www.casqa.org the ditch or swale at the end of this fact sheet). Bypass or side-cutting can occur if a sufficient spillway is not provided in the center of the dam. Check dams are usually constructed of rock, gravel bags, sandbags, and fiber rolls. A number of products can also be used as check dams (e.g. HDPE check dams, temporary silt dikes (SE-12)), and some of these products can be removed and reused. Check dams can also be constructed of logs or lumber, and have the advantage of a longer lifespan when compared to gravel bags, sandbags, and fiber rolls. Check dams should not be constructed from straw bales or silt fences, since concentrated flows quickly wash out these materials. Rock check dams are usually constructed of 8 to 12 in. rock. The rock is placed either by hand or mechanically, but never just dumped into the channel. The dam should completely span the ditch or swale to prevent washout. The rock used should be large enough to stay in place given the expected design flow through the channel. It is recommended that abutments be extended 18 in. into the channel bank. Rock can be graded such that smaller diameter rock (e.g. 2-4 in) is located on the upstream side of larger rock (holding the smaller rock in place); increasing residence time. Log check dams are usually constructed of 4 to 6 in. diameter logs, installed vertically. The logs should be embedded into the soil at least 18 in. Logs can be bolted or wired to vertical support logs that have been driven or buried into the soil. See fiber rolls, SE-5, for installation of fiber roll check dams. Gravel bag and sand bag check dams are constructed by stacking bags across the ditch or swale, shaped as shown in the drawings at the end of this fact sheet at the end of this fact sheet). Manufactured products, such as temporary silt dikes (SE-12), should be installed in accordance Installation typically requires anchoring or trenching of products, as well as regular maintenance to remove accumulated sediment and debris. If grass is planted to stabilize the ditch or swale, the check dam should be removed when the grass has matured (unless the slope of the swales is greater than 4%). The following guidance should be followed for the design and layout of check dams: Install the first check dam approximately 16 ft from the outfall device and at regular intervals based on slope gradient and soil type. Check dams should be placed at a distance and height to allow small pools to form between each check dam. For multiple check dam installation, backwater from a downstream check dam should reach the toes of the upstream check dam. A sediment trap provided immediately upstream of the check dam will help capture sediment. Due to the potential for this sediment to be resuspended in subsequent storms, the sediment trap should be cleaned following each storm event. Check Dams SE-4 July 2012 California Stormwater BMP Handbook Portal 4 of 7 Construction www.casqa.org High flows (typically a 2-year storm or larger) should safely flow over the check dam without an increase in upstream flooding or damage to the check dam. Where grass is used to line ditches, check dams should be removed when grass has matured sufficiently to protect the ditch or swale. Materials Rock used for check dams should typically be 8-12 in rock and be sufficiently sized to stay in place given expected design flows in the channel. Smaller diameter rock (e.g. 2 to 4 in) can be placed on the upstream side of larger rock to increase residence time. Gravel bags used for check dams should conform to the requirements of SE-6, Gravel Bag Berms. Sandbags used for check dams should conform to SE-8, Sandbag Barrier. Fiber rolls used for check dams should conform to SE-5, Fiber Rolls. Temporary silt dikes used for check dams should conform to SE-12, Temporary Silt Dikes. Installation Rock should be placed individually by hand or by mechanical methods (no dumping of rock) to achieve complete ditch or swale coverage. Tightly abut bags and stack according to detail shown in the figure at the end of this section (pyramid approach). Gravel bags and sandbags should not be stacked any higher than 3 ft. Upper rows or gravel and sand bags shall overlap joints in lower rows. Fiber rolls should be trenched in, backfilled, and firmly staked in place. Install along a level contour. HDPE check dams, temporary silt dikes, and other manufactured products should be used and installed per manufacturer specifications. Costs Cost consists of labor costs if materials are readily available (such as gravel on-site). If material must be imported, costs will increase. For other material and installation costs, see SE-5, SE-6, SE-8, SE-12, and SE-14. Inspection and Maintenance BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Replace missing rock, bags, rolls, etc. Replace bags or rolls that have degraded or have become damaged. Check Dams SE-4 July 2012 California Stormwater BMP Handbook Portal 5 of 7 Construction www.casqa.org If the check dam is used as a sediment capture device, sediment that accumulates behind the BMP should be periodically removed in order to maintain BMP effectiveness. Sediment should be removed when the sediment accumulation reaches one-third of the barrier height. If the check dam is used as a grade control structure, sediment removal is not required as long as the system continues to control the grade. Inspect areas behind check dams for pools of standing water, especially if subjected to daily non-stormwater discharges. Remove accumulated sediment prior to permanent seeding or soil stabilization. Remove check dam and accumulated sediment when check dams are no longer needed. References Draft Sedimentation and Erosion Control, and Inventory of Current Practices, USEPA, April 1990. Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995. Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003. Stormwater Management of the Puget Sound Basin, Technical Manual, Publication #91-75, Washington State Department of Ecology, February 1992. Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005. Metzger, M.E. 2004. Managing mosquitoes in stormwater treatment devices. University of California Division of Agriculture and Natural Resources, Publication 8125. On-line: http:// anrcatalog.ucdavis.edu/pdf/8125.pdf Check Dams SE-4 July 2012 California Stormwater BMP Handbook Portal 6 of 7 Construction www.casqa.org Check Dams SE-4 July 2012 California Stormwater BMP Handbook Portal 7 of 7 Construction www.casqa.org Gravel Bag Berm SE-6 May 2011 California Stormwater BMP Handbook Portal 1 of 4 Construction www.casqa.org Description and Purpose A gravel bag berm is a series of gravel-filled bags placed on a level contour to intercept sheet flows. Gravel bags pond sheet flow runoff, allowing sediment to settle out, and release runoff slowly as sheet flow, preventing erosion. Suitable Applications Gravel bag berms may be suitable: As a linear sediment control measure: -Below the toe of slopes and erodible slopes -As sediment traps at culvert/pipe outlets -Below other small cleared areas -Along the perimeter of a site -Down slope of exposed soil areas -Around temporary stockpiles and spoil areas -Parallel to a roadway to keep sediment off paved areas -Along streams and channels As a linear erosion control measure: -Along the face and at grade breaks of exposed and erodible slopes to shorten slope length and spread runoff as sheet flow. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Category Secondary Category Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives SE-1 Silt Fence SE-5 Fiber Roll SE-8 Sandbag Barrier SE-12 Temporary Silt Dike SE-14 Biofilter Bags If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Gravel Bag Berm SE-6 May 2011 California Stormwater BMP Handbook Portal 2 of 4 Construction www.casqa.org -At the top of slopes to divert runoff away from disturbed slopes. -As chevrons (small check dams)across mildly sloped construction roads. For use check dam use in channels, see SE-4, Check Dams. Limitations Gravel berms may be difficult to remove. Removal problems limit their usefulness in landscaped areas. Gravel bag berm may not be appropriate for drainage areas greater than 5 acres. Runoff will pond upstream of the berm, possibly causing flooding if sufficient space does not exist. Degraded gravel bags may rupture when removed, spilling contents. Installation can be labor intensive. Durability of gravel bags is somewhat limited and bags may need to be replaced when installation is required for longer than 6 months. Easily damaged by construction equipment. When used to detain concentrated flows, maintenance requirements increase. Implementation General A gravel bag berm consists of a row of open graded gravel-filled bags placed on a level contour. When appropriately placed, a gravel bag berm intercepts and slows sheet flow runoff, causing temporary ponding. The temporary ponding allows sediment to settle. The open graded gravel in the bags is porous, which allows the ponded runoff to flow slowly through the bags, releasing the runoff as sheet flows. Gravel bag berms also interrupt the slope length and thereby reduce erosion by reducing the tendency of sheet flows to concentrate into rivulets, which erode rills, and ultimately gullies, into disturbed, sloped soils. Gravel bag berms are similar to sand bag barriers, but are more porous.Generally, gravel bag berms should be used in conjunction with temporary soil stabilization controls up slope to provide effective erosion and sediment control. Design and Layout Locate gravel bag berms on level contours. When used for slope interruption, the following slope/sheet flow length combinations apply: -Slope inclination of 4:1 (H:V) or flatter: Gravel bags should be placed at a maximum interval of 20 ft, with the first row near the slope toe. -Slope inclination between 4:1 and 2:1 (H:V): Gravel bags should be placed at a maximum interval of 15 ft. (a closer spacing is more effective), with the first row near the slope toe. Gravel Bag Berm SE-6 May 2011 California Stormwater BMP Handbook Portal 3 of 4 Construction www.casqa.org Slope inclination 2:1 (H:V) or greater: Gravel bags should be placed at a maximum interval of 10 ft. (a closer spacing is more effective), with the first row near the slope toe. Turn the ends of the gravel bag barriers up slope to prevent runoff from going around the berm. Allow sufficient space up slope from the gravel bag berm to allow ponding, and to provide room for sediment storage. For installation near the toe of the slope, gravel bag barriers should be set back from the slope toe to facilitate cleaning. Where specific site conditions do not allow for a set-back, the gravel bag barrier may be constructed on the toe of the slope. To prevent flows behind the barrier, bags can be placed perpendicular to a berm to serve as cross barriers. Drainage area should not exceed 5 acres. In Non-Traffic Areas: -Height = 18 in. maximum -Top width = 24 in. minimum for three or more layer construction -Top width =12 in. minimum for one or two layer construction -Side slopes = 2:1 (H:V) or flatter In Construction Traffic Areas: -Height = 12 in. maximum -Top width = 24 in. minimum for three or more layer construction. -Top width = 12 in. minimum for one or two layer construction. -Side slopes = 2:1 (H:V) or flatter. Butt ends of bags tightly. On multiple row, or multiple layer construction, overlap butt joints of adjacent row and row beneath. Use a pyramid approach when stacking bags. Materials Bag Material:Bags should be woven polypropylene, polyethylene or polyamide fabric or burlap, minimum unit weight of 4 ounces/yd2, Mullen burst strength exceeding 300 lb/in2 in conformance with the requirements in ASTM designation D3786, and ultraviolet stability exceeding 70% in conformance with the requirements in ASTM designation D4355. Gravel Bag Berm SE-6 May 2011 California Stormwater BMP Handbook Portal 4 of 4 Construction www.casqa.org Bag Size:Each gravel-filled bag should have a length of 18 in., width of 12 in., thickness of 3 in., and mass of approximately 33 lbs. Bag dimensions are nominal, and may vary based on locally available materials. Fill Material:Fill material should be 0.5 to 1 in. crushed rock, clean and free from clay, organic matter, and other deleterious material, or other suitable open graded, non-cohesive, porous gravel. Costs Material costs for gravel bags are average and are dependent upon material availability. $2.50- 3.00 per filled gravel bag is standard based upon vendor research. Inspection and Maintenance BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Gravel bags exposed to sunlight will need to be replaced every two to three months due to degrading of the bags. Reshape or replace gravel bags as needed. Repair washouts or other damage as needed. Sediment that accumulates in the BMP should be periodically removed in order to maintain BMP effectiveness. Sediment should be removed when the sediment accumulation reaches one-third of the barrier height. Remove gravel bag berms when no longer needed and recycle gravel fill whenever possible and properly dispose of bag material. Remove sediment accumulation and clean, re-grade, and stabilize the area. References Handbook of Steel Drainage and Highway Construction, American Iron and Steel Institute, 1983. Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003. Stormwater Pollution Plan Handbook, First Edition, State of California, Department of Transportation Division of New Technology, Materials and Research, October 1992. Erosion and Sediment Control Manual,Oregon Department of Environmental Quality, February 2005. Street Sweeping and Vacuuming SE-7 January 2011 California Stormwater BMP Handbook 1 of 2 Construction www.casqa.org Description and Purpose Street sweeping and vacuuming includes use of self-propelled and walk-behind equipment to remove sediment from streets and roadways, and to clean paved surfaces in preparation for final paving. Sweeping and vacuuming prevents sediment from the project site from entering storm drains or receiving waters. Suitable Applications Sweeping and vacuuming are suitable anywhere sediment is tracked from the project site onto public or private paved streets and roads, typically at points of egress. Sweeping and vacuuming are also applicable during preparation of paved surfaces for final paving. Limitations Sweeping and vacuuming may not be effective when sediment is wet or when tracked soil is caked (caked soil may need to be scraped loose). Implementation Controlling the number of points where vehicles can leave the site will allow sweeping and vacuuming efforts to be focused, and perhaps save money. Inspect potential sediment tracking locations daily. Visible sediment tracking should be swept or vacuumed on a daily basis. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Street Sweeping and Vacuuming SE-7 January 2011 California Stormwater BMP Handbook 2 of 2 Construction www.casqa.org Do not use kick brooms or sweeper attachments. These tend to spread the dirt rather than remove it. If not mixed with debris or trash, consider incorporating the removed sediment back into the project Costs Rental rates for self-propelled sweepers vary depending on hopper size and duration of rental. Expect rental rates from $58/hour (3 yd3 hopper) to $88/hour (9 yd3 hopper), plus operator costs. Hourly production rates vary with the amount of area to be swept and amount of sediment. Match the hopper size to the area and expect sediment load to minimize time spent dumping. Inspection and Maintenance Inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. When actively in use, points of ingress and egress must be inspected daily. When tracked or spilled sediment is observed outside the construction limits, it must be removed at least daily. More frequent removal, even continuous removal, may be required in some jurisdictions. Be careful not to sweep up any unknown substance or any object that may be potentially hazardous. Adjust brooms frequently; maximize efficiency of sweeping operations. After sweeping is finished, properly dispose of sweeper wastes at an approved dumpsite. References Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Labor Surcharge and Equipment Rental Rates, State of California Department of Transportation (Caltrans), April 1, 2002 –March 31, 2003. Storm Drain Inlet Protection SE-10 July 2012 California Stormwater BMP Handbook 1 of 10 Construction www.casqa.org Description and Purpose Storm drain inlet protection consists of a sediment filter or an impounding area in, around or upstream of a storm drain, drop inlet, or curb inlet. Storm drain inlet protection measures temporarily pond runoff before it enters the storm drain, allowing sediment to settle. Some filter configurations also remove sediment by filtering, but usually the ponding action results in the greatest sediment reduction. Temporary geotextile storm drain inserts attach underneath storm drain grates to capture and filter storm water. Suitable Applications Every storm drain inlet receiving runoff from unstabilized or otherwise active work areas should be protected. Inlet protection should be used in conjunction with other erosion and sediment controls to prevent sediment-laden stormwater and non-stormwater discharges from entering the storm drain system. Limitations Drainage area should not exceed 1 acre. In general straw bales should not be used as inlet protection. Requires an adequate area for water to pond without encroaching into portions of the roadway subject to traffic. Sediment removal may be inadequate to prevent sediment discharges in high flow conditions or if runoff is heavily sediment laden. If high flow conditions are expected, use Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Category Secondary Category Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives SE-1 Silt Fence SE-5 Fiber Rolls SE-6 Gravel Bag Berm SE-8 Sandbag Barrier SE-14 Biofilter Bags SE-13 Compost Socks and Berms If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Storm Drain Inlet Protection SE-10 July 2012 California Stormwater BMP Handbook 2 of 10 Construction www.casqa.org other onsite sediment trapping techniques in conjunction with inlet protection. Frequent maintenance is required. Limit drainage area to 1 acre maximum. For drainage areas larger than 1 acre, runoff should be routed to a sediment-trapping device designed for larger flows. See BMPs SE-2, Sediment Basin, and SE-3, Sediment Traps. Excavated drop inlet sediment traps are appropriate where relatively heavy flows are expected, and overflow capability is needed. Implementation General Inlet control measures presented in this handbook should not be used for inlets draining more than one acre. Runoff from larger disturbed areas should be first routed through SE-2, Sediment Basin or SE-3, Sediment Trap and/or used in conjunction with other drainage control, erosion control, and sediment control BMPs to protect the site. Different types of inlet protection are appropriate for different applications depending on site conditions and the type of inlet. Alternative methods are available in addition to the methods described/shown herein such as prefabricated inlet insert devices, or gutter protection devices. Design and Layout Identify existing and planned storm drain inlets that have the potential to receive sediment- laden surface runoff. Determine if storm drain inlet protection is needed and which method to use. The key to successful and safe use of storm drain inlet protection devices is to know where runoff that is directed toward the inlet to be protected will pond or be diverted as a result of installing the protection device. - Determine the acceptable location and extent of ponding in the vicinity of the drain inlet. The acceptable location and extent of ponding will influence the type and design of the storm drain inlet protection device. - Determine the extent of potential runoff diversion caused by the storm drain inlet protection device. Runoff ponded by inlet protection devices may flow around the device and towards the next downstream inlet. In some cases, this is acceptable; in other cases, serious erosion or downstream property damage can be caused by these diversions. The possibility of runoff diversions will influence whether or not storm drain inlet protection is suitable; and, if suitable, the type and design of the device. The location and extent of ponding, and the extent of diversion, can usually be controlled through appropriate placement of the inlet protection device. In some cases, moving the inlet protection device a short distance upstream of the actual inlet can provide more efficient sediment control, limit ponding to desired areas, and prevent or control diversions. Seven types of inlet protection are presented below. However, it is recognized that other effective methods and proprietary devices exist and may be selected. Storm Drain Inlet Protection SE-10 July 2012 California Stormwater BMP Handbook 3 of 10 Construction www.casqa.org - Silt Fence: Appropriate for drainage basins with less than a 5% slope, sheet flows, and flows under 0.5 cfs. - Excavated Drop Inlet Sediment Trap: An excavated area around the inlet to trap sediment (SE-3). - Gravel bag barrier: Used to create a small sediment trap upstream of inlets on sloped, paved streets. Appropriate for sheet flow or when concentrated flow may exceed 0.5 cfs, and where overtopping is required to prevent flooding. - Block and Gravel Filter: Appropriate for flows greater than 0.5 cfs. - Temporary Geotextile Storm drain Inserts: Different products provide different features. Refer to manufacturer details for targeted pollutants and additional features. - Biofilter Bag Barrier: Used to create a small retention area upstream of inlets and can be located on pavement or soil. Biofilter bags slowly filter runoff allowing sediment to settle out. Appropriate for flows under 0.5 cfs. - Compost Socks: Allow filtered run-off to pass through the compost while retaining sediment and potentially other pollutants (SE-13). Appropriate for flows under 1.0 cfs. Select the appropriate type of inlet protection and design as referred to or as described in this fact sheet. Provide area around the inlet for water to pond without flooding structures and property. Grates and spaces around all inlets should be sealed to prevent seepage of sediment-laden water. Excavate sediment sumps (where needed) 1 to 2 ft with 2:1 side slopes around the inlet. Installation DI Protection Type 1 - Silt Fence - Similar to constructing a silt fence; see BMP SE-1, Silt Fence. Do not place fabric underneath the inlet grate since the collected sediment may fall into the drain inlet when the fabric is removed or replaced and water flow through the grate will be blocked resulting in flooding. See typical Type 1 installation details at the end of this fact sheet. 1. Excavate a trench approximately 6 in. wide and 6 in. deep along the line of the silt fence inlet protection device. 2. Place 2 in. by 2 in. wooden stakes around the perimeter of the inlet a maximum of 3 ft apart and drive them at least 18 in. into the ground or 12 in. below the bottom of the trench. The stakes should be at least 48 in. 3. Lay fabric along bottom of trench, up side of trench, and then up stakes. See SE-1, Silt Fence, for details. The maximum silt fence height around the inlet is 24 in. 4. Staple the filter fabric (for materials and specifications, see SE-1, Silt Fence) to wooden stakes. Use heavy-duty wire staples at least 1 in. in length. Storm Drain Inlet Protection SE-10 July 2012 California Stormwater BMP Handbook 4 of 10 Construction www.casqa.org 5. Backfill the trench with gravel or compacted earth all the way around. DI Protection Type 2 - Excavated Drop Inlet Sediment Trap - Install filter fabric fence in accordance with DI Protection Type 1. Size excavated trap to provide a minimum storage capacity calculated at the rate 67 yd3/acre of drainage area. See typical Type 2 installation details at the end of this fact sheet. DI Protection Type 3 - Gravel bag - Flow from a severe storm should not overtop the curb. In areas of high clay and silts, use filter fabric and gravel as additional filter media. Construct gravel bags in accordance with SE-6, Gravel Bag Berm. Gravel bags should be used due to their high permeability. See typical Type 3 installation details at the end of this fact sheet. 1. Construct on gently sloping street. 2. Leave room upstream of barrier for water to pond and sediment to settle. 3. Place several layers of gravel bags overlapping the bags and packing them tightly together. 4. Leave gap of one bag on the top row to serve as a spillway. Flow from a severe storm (e.g., 10 year storm) should not overtop the curb. DI Protection Type 4 Block and Gravel Filter - Block and gravel filters are suitable for curb inlets commonly used in residential, commercial, and industrial construction. See typical Type 4 installation details at the end of this fact sheet. 1. Place hardware cloth or comparable wire mesh with 0.5 in. openings over the drop inlet so that the wire extends a minimum of 1 ft beyond each side of the inlet structure. If more than one strip is necessary, overlap the strips. Place woven geotextile over the wire mesh. 2. Place concrete blocks lengthwise on their sides in a single row around the perimeter of the inlet, so that the open ends face outward, not upward. The ends of adjacent blocks should abut. The height of the barrier can be varied, depending on design needs, by stacking combinations of blocks that are 4 in., 8 in., and 12 in. wide. The row of blocks should be at least 12 in. but no greater than 24 in. high. 3. Place wire mesh over the outside vertical face (open end) of the concrete blocks to prevent stone from being washed through the blocks. Use hardware cloth or comparable wire mesh with 0.5 in. opening. 4. Pile washed stone against the wire mesh to the top of the blocks. Use 0.75 to 3 in. DI Protection Type 5 Temporary Geotextile Insert (proprietary) Many types of temporary inserts are available. Most inserts fit underneath the grate of a drop inlet or inside of a curb inlet and are fastened to the outside of the grate or curb. These inserts are removable and many can be cleaned and reused. Installation of these inserts differs between manufacturers. Please refer to manufacturer instruction for installation of proprietary devices. Storm Drain Inlet Protection SE-10 July 2012 California Stormwater BMP Handbook 5 of 10 Construction www.casqa.org DI Protection Type 6 - Biofilter bags Biofilter bags may be used as a substitute for gravel bags in low-flow situations. Biofilter bags should conform to specifications detailed in SE-14, Biofilter bags. 1. Construct in a gently sloping area. 2. Biofilter bags should be placed around inlets to intercept runoff flows. 3. All bag joints should overlap by 6 in. 4. Leave room upstream for water to pond and for sediment to settle out. 5. Stake bags to the ground as described in the following detail. Stakes may be omitted if bags are placed on a paved surface. DI Protection Type 7 Compost Socks A compost sock can be assembled on site by filling a mesh sock (e.g., with a pneumatic blower). Compost socks do not require special trenching compared to other sediment control methods (e.g., silt fence). Compost socks should conform to specification detailed in SE-13, Compost Socks and Berms. Costs Average annual cost for installation and maintenance of DI Type 1-4 and 6 (one year useful life) is $200 per inlet. Temporary geotextile inserts are proprietary and cost varies by region. These inserts can often be reused and may have greater than 1 year of use if maintained and kept undamaged. Average cost per insert ranges from $50-75 plus installation, but costs can exceed $100. This cost does not include maintenance. See SE-13 for Compost Sock cost information. Inspection and Maintenance BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Silt Fences. If the fabric becomes clogged, torn, or degrades, it should be replaced. Make sure the stakes are securely driven in the ground and are in good shape (i.e., not bent, cracked, or splintered, and are reasonably perpendicular to the ground). Replace damaged stakes. At a minimum, remove the sediment behind the fabric fence when accumulation reaches one-third the height of the fence or barrier height. Gravel Filters. If the gravel becomes clogged with sediment, it should be carefully removed from the inlet and either cleaned or replaced. Since cleaning gravel at a construction site may be difficult, consider using the sediment-laden stone as fill material and put fresh stone around the inlet. Inspect bags for holes, gashes, and snags, and replace bags as needed. Check gravel bags for proper arrangement and displacement. Storm Drain Inlet Protection SE-10 July 2012 California Stormwater BMP Handbook 6 of 10 Construction www.casqa.org Sediment that accumulates in the BMP should be periodically removed in order to maintain BMP effectiveness. Sediment should be removed when the sediment accumulation reaches one-third of the barrier height. Inspect and maintain temporary geotextile specifications. Remove storm drain inlet protection once the drainage area is stabilized. - Clean and regrade area around the inlet and clean the inside of the storm drain inlet, as it should be free of sediment and debris at the time of final inspection. References Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003. Stormwater Management Manual for The Puget Sound Basin, Washington State Department of Ecology, Public Review Draft, 1991. Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005. Storm Drain Inlet Protection SE-10 July 2012 California Stormwater BMP Handbook 7 of 10 Construction www.casqa.org Storm Drain Inlet Protection SE-10 June 2012 California Stormwater BMP Handbook 8 of 10 Construction www.casqa.org Storm Drain Inlet Protection SE-10 June 2012 California Stormwater BMP Handbook 9 of 10 Construction www.casqa.org Gravel bags Gravel bags 6. Protection can be effective even if it is not immediately adjacent to the inlet provided that the inlet is protected from potential sources of pollution. Storm Drain Inlet Protection SE-10 June 2012 California Stormwater BMP Handbook 10 of 10 Construction www.casqa.org Stabilized Construction Entrance/Exit TC-1 July 2012 California Stormwater BMP Handbook 1 of 6 Construction www.casqa.org Description and Purpose A stabilized construction access is defined by a point of entrance/exit to a construction site that is stabilized to reduce the tracking of mud and dirt onto public roads by construction vehicles. Suitable Applications Use at construction sites: Where dirt or mud can be tracked onto public roads. Adjacent to water bodies. Where poor soils are encountered. Where dust is a problem during dry weather conditions. Limitations Entrances and exits require periodic top dressing with additional stones. This BMP should be used in conjunction with street sweeping on adjacent public right of way. Entrances and exits should be constructed on level ground only. Stabilized construction entrances are rather expensive to construct and when a wash rack is included, a sediment trap of some kind must also be provided to collect wash water runoff. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Stabilized Construction Entrance/Exit TC-1 July 2012 California Stormwater BMP Handbook 2 of 6 Construction www.casqa.org Implementation General A stabilized construction entrance is a pad of aggregate underlain with filter cloth located at any point where traffic will be entering or leaving a construction site to or from a public right of way, street, alley, sidewalk, or parking area. The purpose of a stabilized construction entrance is to reduce or eliminate the tracking of sediment onto public rights of way or streets. Reducing tracking of sediments and other pollutants onto paved roads helps prevent deposition of sediments into local storm drains and production of airborne dust. Where traffic will be entering or leaving the construction site, a stabilized construction entrance should be used. NPDES permits require that appropriate measures be implemented to prevent tracking of sediments onto paved roadways, where a significant source of sediments is derived from mud and dirt carried out from unpaved roads and construction sites. Stabilized construction entrances are moderately effective in removing sediment from equipment leaving a construction site. The entrance should be built on level ground. Advantages of the Stabilized Construction Entrance/Exit is that it does remove some sediment from equipment and serves to channel construction traffic in and out of the site at specified locations. Efficiency is greatly increased when a washing rack is included as part of a stabilized construction entrance/exit. Design and Layout Construct on level ground where possible. Select 3 to 6 in. diameter stones. Use minimum depth of stones of 12 in. or as recommended by soils engineer. Construct length of 50 ft or maximum site will allow, and 10 ft minimum width or to accommodate traffic. Rumble racks constructed of steel panels with ridges and installed in the stabilized entrance/exit will help remove additional sediment and to keep adjacent streets clean. Provide ample turning radii as part of the entrance. Limit the points of entrance/exit to the construction site. Limit speed of vehicles to control dust. Properly grade each construction entrance/exit to prevent runoff from leaving the construction site. Route runoff from stabilized entrances/exits through a sediment trapping device before discharge. Design stabilized entrance/exit to support heaviest vehicles and equipment that will use it. Stabilized Construction Entrance/Exit TC-1 July 2012 California Stormwater BMP Handbook 3 of 6 Construction www.casqa.org Select construction access stabilization (aggregate, asphaltic concrete, concrete) based on longevity, required performance, and site conditions. Do not use asphalt concrete (AC) grindings for stabilized construction access/roadway. If aggregate is selected, place crushed aggregate over geotextile fabric to at least 12 in. depth, or place aggregate to a depth recommended by a geotechnical engineer. A crushed aggregate greater than 3 in. but smaller than 6 in. should be used. Designate combination or single purpose entrances and exits to the construction site. Require that all employees, subcontractors, and suppliers utilize the stabilized construction access. Implement SE-7, Street Sweeping and Vacuuming, as needed. All exit locations intended to be used for more than a two-week period should have stabilized construction entrance/exit BMPs. Inspection and Maintenance Inspect and verify that activity–based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMPs are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Inspect local roads adjacent to the site daily. Sweep or vacuum to remove visible accumulated sediment. Remove aggregate, separate and dispose of sediment if construction entrance/exit is clogged with sediment. Keep all temporary roadway ditches clear. Check for damage and repair as needed. Replace gravel material when surface voids are visible. Remove all sediment deposited on paved roadways within 24 hours. Remove gravel and filter fabric at completion of construction Costs Average annual cost for installation and maintenance may vary from $1,200 to $4,800 each, averaging $2,400 per entrance. Costs will increase with addition of washing rack, and sediment trap. With wash rack, costs range from $1,200 -$6,000 each, averaging $3,600 per entrance. References Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995. Stabilized Construction Entrance/Exit TC-1 July 2012 California Stormwater BMP Handbook 4 of 6 Construction www.casqa.org National Management Measures to Control Nonpoint Source Pollution from Urban Areas, USEPA Agency, 2002. Proposed Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters, Work Group Working Paper, USEPA, April 1992. Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Stormwater Management of the Puget Sound Basin,Technical Manual, Publication #91-75, Washington State Department of Ecology, February 1992. Virginia Erosion and Sedimentation Control Handbook, Virginia Department of Conservation and Recreation, Division of Soil and Water Conservation, 1991. Guidance Specifying Management Measures for Nonpoint Pollution in Coastal Waters,EPA 840-B-9-002,USEPA, Office of Water, Washington, DC,1993. Water Quality Management Plan for the Lake Tahoe Region, Volume II, Handbook of Management Practices, Tahoe Regional Planning Agency,November 1988. Stabilized Construction Entrance/Exit TC-1 July 2012 California Stormwater BMP Handbook 5 of 6 Construction www.casqa.org 50’ Typical (1) Length should be extended to 12 times the diameter of the largest construction vehicle tire. (2) On small sites length should be the maximum allowed by site. Stabilized Construction Entrance/Exit TC-1 July 2012 California Stormwater BMP Handbook 6 of 6 Construction www.casqa.org 50’ Typical (1) Length should be extended to 12 times the diameter of the largest construction vehicle tire. (2) On small sites length should be the maximum allowed by site. Entrance/Outlet Tire Wash TC-3 January 2011 California Stormwater BMP Handbook 1 of 3 Construction www.casqa.org Description and Purpose A tire wash is an area located at stabilized construction access points to remove sediment from tires and under carriages and to prevent sediment from being transported onto public roadways. Suitable Applications Tire washes may be used on construction sites where dirt and mud tracking onto public roads by construction vehicles may occur. Limitations The tire wash requires a supply of wash water. A turnout or doublewide exit is required to avoid having entering vehicles drive through the wash area. Do not use where wet tire trucks leaving the site leave the road dangerously slick. Implementation Incorporate with a stabilized construction entrance/exit. See TC-1, Stabilized Construction Entrance/Exit. Construct on level ground when possible, on a pad of coarse aggregate greater than 3 in. but smaller than 6 in. A geotextile fabric should be placed below the aggregate. Wash rack should be designed and constructed/manufactured for anticipated traffic loads. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives TC-1 Stabilized Construction Entrance/Exit If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Entrance/Outlet Tire Wash TC-3 January 2011 California Stormwater BMP Handbook 2 of 3 Construction www.casqa.org Provide a drainage ditch that will convey the runoff from the wash area to a sediment trapping device. The drainage ditch should be of sufficient grade, width, and depth to carry the wash runoff. Use hoses with automatic shutoff nozzles to prevent hoses from being left on. Require that all employees, subcontractors, and others that leave the site with mud caked tires and undercarriages to use the wash facility. Implement SC-7, Street Sweeping and Vacuuming, as needed. Costs Costs are low for installation of wash rack. Inspection and Maintenance Inspect and verify that activity based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Inspect BMPs subject to non-stormwater discharge daily while non-stormwater discharges occur. Remove accumulated sediment in wash rack and/or sediment trap to maintain system performance. Inspect routinely for damage and repair as needed. References Blueprint for a Clean Bay: Best Management Practices to Prevent Stormwater Pollution from Construction Related Activities; Santa Clara Valley Nonpoint Source Pollution Control Program, 1995. Coastal Nonpoint Pollution Control Program; Program Development and Approval Guidance, Working Group, Working Paper; USEPA, April 1992. Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995. Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Stormwater Management for Construction Activities, Developing Pollution Prevention Plans and Best Management Practices, EPA 832-R-92005; USEPA, April 1992. Entrance/Outlet Tire Wash TC-3 January 2011 California Stormwater BMP Handbook 3 of 3 Construction www.casqa.org Wind Erosion Control WE-1 May 2011 California Stormwater BMP Handbook 1 of 5 Construction www.casqa.org Description and Purpose Wind erosion or dust control consists of applying water or other chemical dust suppressants as necessary to prevent or alleviate dust nuisance generated by construction activities. Covering small stockpiles or areas is an alternative to applying water or other dust palliatives. California’s Mediterranean climate, with a short “wet”season and a typically long,hot “dry”season, allows the soils to thoroughly dry out. During the dry season, construction activities are at their peak, and disturbed and exposed areas are increasingly subject to wind erosion, sediment tracking and dust generated by construction equipment. Site conditions and climate can make dust control more of an erosion problem than water based erosion. Additionally, many local agencies, including Air Quality Management Districts,require dust control and/or dust control permits in order to comply with local nuisance laws, opacity laws (visibility impairment) and the requirements of the Clean Air Act. Wind erosion control is required to be implemented at all construction sites greater than 1 acre by the General Permit. Suitable Applications Most BMPs that provide protection against water-based erosion will also protect against wind-based erosion and dust control requirements required by other agencies will generally meet wind erosion control requirements for water quality protection. Wind erosion control BMPs are suitable during the following construction activities: Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Category Secondary Category Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives EC-5 Soil Binders If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Wind Erosion Control WE-1 May 2011 California Stormwater BMP Handbook 2 of 5 Construction www.casqa.org Construction vehicle traffic on unpaved roads Drilling and blasting activities Soils and debris storage piles Batch drop from front-end loaders Areas with unstabilized soil Final grading/site stabilization Limitations Watering prevents dust only for a short period (generally less than a few hours) and should be applied daily (or more often) to be effective. Over watering may cause erosion and track-out. Oil or oil-treated subgrade should not be used for dust control because the oil may migrate into drainageways and/or seep into the soil. Chemical dust suppression agents may have potential environmental impacts. Selected chemical dust control agents should be environmentally benign. Effectiveness of controls depends on soil, temperature, humidity, wind velocity and traffic. Chemical dust suppression agents should not be used within 100 feet of wetlands or water bodies. Chemically treated subgrades may make the soil water repellant, interfering with long-term infiltration and the vegetation/re-vegetation of the site. Some chemical dust suppressants may be subject to freezing and may contain solvents and should be handled properly. In compacted areas, watering and other liquid dust control measures may wash sediment or other constituents into the drainage system. If the soil surface has minimal natural moisture, the affected area may need to be pre-wetted so that chemical dust control agents can uniformly penetrate the soil surface. Implementation Dust Control Practices Dust control BMPs generally stabilize exposed surfaces and minimize activities that suspend or track dust particles. The following table presents dust control practices that can be applied to varying site conditions that could potentially cause dust. For heavily traveled and disturbed areas,wet suppression (watering), chemical dust suppression, gravel asphalt surfacing, temporary gravel construction entrances, equipment wash-out areas, and haul truck covers can be employed as dust control applications. Permanent or temporary vegetation and mulching can be employed for areas of occasional or no construction traffic. Preventive measures include minimizing surface areas to be disturbed, limiting onsite vehicle traffic to 15 mph or less, and controlling the number and activity of vehicles on a site at any given time. Wind Erosion Control WE-1 May 2011 California Stormwater BMP Handbook 3 of 5 Construction www.casqa.org Chemical dust suppressants include: mulch and fiber based dust palliatives (e.g. paper mulch with gypsum binder), salts and brines (e.g. calcium chloride, magnesium chloride), non- petroleum based organics (e.g. vegetable oil, lignosulfonate), petroleum based organics (e.g. asphalt emulsion, dust oils, petroleum resins), synthetic polymers (e.g. polyvinyl acetate, vinyls, acrylic), clay additives (e.g. bentonite, montimorillonite) and electrochemical products (e.g. enzymes, ionic products). Site Condition Dust Control Practices Permanent Vegetation Mulching Wet Suppression (Watering) Chemical Dust Suppression Gravel or Asphalt Temporary Gravel Construction Entrances/Equipment Wash Down Synthetic Covers Minimize Extent of Disturbed Area Disturbed Areas not Subject to Traffic X X X X X X Disturbed Areas Subject to Traffic X X X X X Material Stockpiles X X X X X Demolition X X X Clearing/ Excavation X X X Truck Traffic on Unpaved Roads X X X X X Tracking X X Additional preventive measures include: Schedule construction activities to minimize exposed area (see EC-1, Scheduling). Quickly treat exposed soils using water, mulching, chemical dust suppressants,or stone/gravel layering. Identify and stabilize key access points prior to commencement of construction. Minimize the impact of dust by anticipating the direction of prevailing winds. Restrict construction traffic to stabilized roadways within the project site, as practicable. Water should be applied by means of pressure-type distributors or pipelines equipped with a spray system or hoses and nozzles that will ensure even distribution. All distribution equipment should be equipped with a positive means of shutoff. Unless water is applied by means of pipelines, at least one mobile unit should be available at all times to apply water or dust palliative to the project. If reclaimed waste water is used, the sources and discharge must meet California Department of Health Services water reclamation criteria and the Regional Water Quality Wind Erosion Control WE-1 May 2011 California Stormwater BMP Handbook 4 of 5 Construction www.casqa.org Control Board (RWQCB) requirements. Non-potable water should not be conveyed in tanks or drain pipes that will be used to convey potable water and there should be no connection between potable and non-potable supplies. Non-potable tanks, pipes, and other conveyances should be marked, “NON-POTABLE WATER -DO NOT DRINK.” Pave or chemically stabilize access points where unpaved traffic surfaces adjoin paved roads. Provide covers for haul trucks transporting materials that contribute to dust. Provide for rapid clean up of sediments deposited on paved roads. Furnish stabilized construction road entrances and wheel wash areas. Stabilize inactive areas of construction sites using temporary vegetation or chemical stabilization methods. For chemical stabilization, there are many products available for chemically stabilizing gravel roadways and stockpiles. If chemical stabilization is used, the chemicals should not create any adverse effects on stormwater, plant life, or groundwater and should meet all applicable regulatory requirements. Costs Installation costs for water and chemical dust suppression vary based on the method used and the length of effectiveness. Annual costs may be high since some of these measures are effective for only a few hours to a few days. Inspection and Maintenance Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities. BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Check areas protected to ensure coverage. Most water-based dust control measures require frequent application,often daily or even multiple times per day. Obtain vendor or independent information on longevity of chemical dust suppressants. References Best Management Practices and Erosion Control Manual for Construction Sites, Flood Control District of Maricopa County, Arizona, September 1992. California Air Pollution Control Laws, California Air Resources Board, updated annually. Construction Manual, Chapter 4,Section 10, “Dust Control”; Section 17, “Watering”; and Section 18, “Dust Palliative”, California Department of Transportation (Caltrans), July 2001. Wind Erosion Control WE-1 May 2011 California Stormwater BMP Handbook 5 of 5 Construction www.casqa.org Prospects for Attaining the State Ambient Air Quality Standards for Suspended Particulate Matter (PM10), Visibility Reducing Particles, Sulfates, Lead, and Hydrogen Sulfide, California Air Resources Board, April 1991. Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003. Material Delivery and Storage WM-1 November 2009 California Stormwater BMP Handbook 1 of 5 Construction www.casqa.org Description and Purpose Prevent, reduce, or eliminate the discharge of pollutants from material delivery and storage to the stormwater system or watercourses by minimizing the storage of hazardous materials onsite, storing materials in watertight containers and/or a completely enclosed designated area, installing secondary containment, conducting regular inspections, and training employees and subcontractors. This best management practice covers only material delivery and storage. For other information on materials, see WM-2, Material Use, or WM-4, Spill Prevention and Control. For information on wastes, see the waste management BMPs in this section. Suitable Applications These procedures are suitable for use at all construction sites with delivery and storage of the following materials: Soil stabilizers and binders Pesticides and herbicides Fertilizers Detergents Plaster Petroleum products such as fuel, oil, and grease Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Category Secondary Category Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Material Delivery and Storage WM-1 November 2009 California Stormwater BMP Handbook 2 of 5 Construction www.casqa.org Asphalt and concrete components Hazardous chemicals such as acids, lime, glues, adhesives, paints, solvents, and curing compounds Concrete compounds Other materials that may be detrimental if released to the environment Limitations Space limitation may preclude indoor storage. Storage sheds often must meet building and fire code requirements. Implementation The following steps should be taken to minimize risk: Chemicals must be stored in water tight containers with appropriate secondary containment or in a storage shed. When a material storage area is located on bare soil, the area should be lined and bermed. Use containment pallets or other practical and available solutions, such as storing materials within newly constructed buildings or garages, to meet material storage requirements. Stack erodible landscape material on pallets and cover when not in use. Contain all fertilizers and other landscape materials when not in use. Temporary storage areas should be located away from vehicular traffic. Material Safety Data Sheets (MSDS) should be available on-site for all materials stored that have the potential to effect water quality. Construction site areas should be designated for material delivery and storage. Material delivery and storage areas should be located away from waterways, if possible. -Avoid transport near drainage paths or waterways. -Surround with earth berms or other appropriate containment BMP. See EC-9, Earth Dikes and Drainage Swales. -Place in an area that will be paved. Storage of reactive, ignitable, or flammable liquids must comply with the fire codes of your area. Contact the local Fire Marshal to review site materials, quantities, and proposed storage area to determine specific requirements. See the Flammable and Combustible Liquid Code, NFPA30. An up to date inventory of materials delivered and stored onsite should be kept. Material Delivery and Storage WM-1 November 2009 California Stormwater BMP Handbook 3 of 5 Construction www.casqa.org Hazardous materials storage onsite should be minimized. Hazardous materials should be handled as infrequently as possible. Keep ample spill cleanup supplies appropriate for the materials being stored. Ensure that cleanup supplies are in a conspicuous, labeled area. Employees and subcontractors should be trained on the proper material delivery and storage practices. Employees trained in emergency spill cleanup procedures must be present when dangerous materials or liquid chemicals are unloaded. If significant residual materials remain on the ground after construction is complete, properly remove and dispose of materials and any contaminated soil. See WM-7, Contaminated Soil Management. If the area is to be paved, pave as soon as materials are removed to stabilize the soil. Material Storage Areas and Practices Liquids, petroleum products, and substances listed in 40 CFR Parts 110, 117, or 302 should be stored in approved containers and drums and should not be overfilled. Containers and drums should be placed in temporary containment facilities for storage. A temporary containment facility should provide for a spill containment volume able to contain precipitation from a 25 year storm event, plus the greater of 10% of the aggregate volume of all containers or 100% of the capacity of the largest container within its boundary, whichever is greater. A temporary containment facility should be impervious to the materials stored therein for a minimum contact time of 72 hours. A temporary containment facility should be maintained free of accumulated rainwater and spills. In the event of spills or leaks, accumulated rainwater and spills should be collected and placed into drums. These liquids should be handled as a hazardous waste unless testing determines them to be non-hazardous. All collected liquids or non-hazardous liquids should be sent to an approved disposal site. Sufficient separation should be provided between stored containers to allow for spill cleanup and emergency response access. Incompatible materials, such as chlorine and ammonia, should not be stored in the same temporary containment facility. Materials should be covered prior to, and during rain events. Materials should be stored in their original containers and the original product labels should be maintained in place in a legible condition. Damaged or otherwise illegible labels should be replaced immediately. Material Delivery and Storage WM-1 November 2009 California Stormwater BMP Handbook 4 of 5 Construction www.casqa.org Bagged and boxed materials should be stored on pallets and should not be allowed to accumulate on the ground. To provide protection from wind and rain throughout the rainy season, bagged and boxed materials should be covered during non-working days and prior to and during rain events. Stockpiles should be protected in accordance with WM-3, Stockpile Management. Materials should be stored indoors within existing structures or completely enclosed storage sheds when available. Proper storage instructions should be posted at all times in an open and conspicuous location. An ample supply of appropriate spill clean up material should be kept near storage areas. Also see WM-6, Hazardous Waste Management, for storing of hazardous wastes. Material Delivery Practices Keep an accurate, up-to-date inventory of material delivered and stored onsite. Arrange for employees trained in emergency spill cleanup procedures to be present when dangerous materials or liquid chemicals are unloaded. Spill Cleanup Contain and clean up any spill immediately. Properly remove and dispose of any hazardous materials or contaminated soil if significant residual materials remain on the ground after construction is complete. See WM-7, Contaminated Soil Management. See WM-4, Spill Prevention and Control, for spills of chemicals and/or hazardous materials. If spills or leaks of materials occur that are not contained and could discharge to surface waters, non-visible sampling of site discharge may be required. Refer to the General Permit or to your project specific Construction Site Monitoring Plan to determine if and where sampling is required. Cost The largest cost of implementation may be in the construction of a materials storage area that is covered and provides secondary containment. Inspection and Maintenance BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Keep storage areas clean and well organized, including a current list of all materials onsite. Inspect labels on containers for legibility and accuracy. Material Delivery and Storage WM-1 November 2009 California Stormwater BMP Handbook 5 of 5 Construction www.casqa.org Repair or replace perimeter controls, containment structures, covers, and liners as needed to maintain proper function. References Blueprint for a Clean Bay: Best Management Practices to Prevent Stormwater Pollution from Construction Related Activities; Santa Clara Valley Nonpoint Source Pollution Control Program, 1995. Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance, Working Group Working Paper; USEPA, April 1992. Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003. Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992. Material Use WM-2 November 2009 California Stormwater BMP Handbook 1 of 4 Construction www.casqa.org Description and Purpose Prevent or reduce the discharge of pollutants to the storm drain system or watercourses from material use by using alternative products, minimizing hazardous material use onsite, and training employees and subcontractors. Suitable Applications This BMP is suitable for use at all construction projects. These procedures apply when the following materials are used or prepared onsite: Pesticides and herbicides Fertilizers Detergents Petroleum products such as fuel, oil, and grease Asphalt and other concrete components Other hazardous chemicals such as acids, lime, glues, adhesives, paints, solvents, and curing compounds Other materials that may be detrimental if released to the environment Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Category Secondary Category Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Material Use WM-2 November 2009 California Stormwater BMP Handbook 2 of 4 Construction www.casqa.org Limitations Safer alternative building and construction products may not be available or suitable in every instance. Implementation The following steps should be taken to minimize risk: Minimize use of hazardous materials onsite. Follow manufacturer instructions regarding uses, protective equipment, ventilation, flammability, and mixing of chemicals. Train personnel who use pesticides. The California Department of Pesticide Regulation and county agricultural commissioners license pesticide dealers, certify pesticide applicators, and conduct onsite inspections. The preferred method of termiticide application is soil injection near the existing or proposed structure foundation/slab; however, if not feasible, soil drench application of termiticides should follow EPA label guidelines and the following recommendations (most of which are applicable to most pesticide applications): Do not treat soil that is water-saturated or frozen. Application shall not commence within 24-hours of a predicted precipitation event with a 40% or greater probability. Weather tracking must be performed on a daily basis prior to termiticide application and during the period of termiticide application. Do not allow treatment chemicals to runoff from the target area. Apply proper quantity to prevent excess runoff. Provide containment for and divert stormwater from application areas using berms or diversion ditches during application. Dry season: Do not apply within 10 feet of storm drains. Do not apply within 25 feet of aquatic habitats (such as, but not limited to, lakes; reservoirs; rivers; permanent streams; marshes or ponds; estuaries; and commercial fish farm ponds). Wet season: Do not apply within 50 feet of storm drains or aquatic habitats (such as, but not limited to, lakes; reservoirs; rivers; permanent streams; marshes or ponds; estuaries; and commercial fish farm ponds) unless a vegetative buffer is present (if so, refer to dry season requirements). Do not make on-grade applications when sustained wind speeds are above 10 mph (at application site) at nozzle end height. Cover treatment site prior to a rain event in order to prevent run-off of the pesticide into non-target areas. The treated area should be limited to a size that can be backfilled and/or covered by the end of the work shift. Backfilling or covering of the treated area shall be done by the end of the same work shift in which the application is made. The applicator must either cover the soil him/herself or provide written notification of the above requirement to the contractor on site and to the person commissioning the Material Use WM-2 November 2009 California Stormwater BMP Handbook 3 of 4 Construction www.casqa.org application (if different than the contractor). If notice is provided to the contractor or the person commissioning the application, then they are responsible under the Federal Insecticide Fungicide, and Rodenticide Act (FIFRA) to ensure that: 1) if the concrete slab cannot be poured over the treated soil within 24 hours of application, the treated soil is covered with a waterproof covering (such as polyethylene sheeting), and 2) the treated soil is covered if precipitation is predicted to occur before the concrete slab is scheduled to be poured. Do not over-apply fertilizers, herbicides, and pesticides. Prepare only the amount needed. Follow the recommended usage instructions. Over-application is expensive and environmentally harmful. Unless on steep slopes, till fertilizers into the soil rather than hydraulic application. Apply surface dressings in several smaller applications, as opposed to one large application, to allow time for infiltration and to avoid excess material being carried offsite by runoff. Do not apply these chemicals before predicted rainfall. Train employees and subcontractors in proper material use. Supply Material Safety Data Sheets (MSDS) for all materials. Dispose of latex paint and paint cans, used brushes, rags, absorbent materials, and drop cloths, when thoroughly dry and are no longer hazardous, with other construction debris. Do not remove the original product label; it contains important safety and disposal information. Use the entire product before disposing of the container. Mix paint indoors or in a containment area. Never clean paintbrushes or rinse paint containers into a street, gutter, storm drain, or watercourse. Dispose of any paint thinners, residue, and sludge(s) that cannot be recycled, as hazardous waste. For water-based paint, clean brushes to the extent practicable, and rinse to a drain leading to a sanitary sewer where permitted, or contain for proper disposal off site. For oil-based paints, clean brushes to the extent practicable, and filter and reuse thinners and solvents. Use recycled and less hazardous products when practical. Recycle residual paints, solvents, non-treated lumber, and other materials. Use materials only where and when needed to complete the construction activity. Use safer alternative materials as much as possible. Reduce or eliminate use of hazardous materials onsite when practical. Document the location, time, chemicals applied, and applicator’s name and qualifications. Keep an ample supply of spill clean up material near use areas. Train employees in spill clean up procedures. Avoid exposing applied materials to rainfall and runoff unless sufficient time has been allowed for them to dry. Discontinue use of erodible landscape material within 2 days prior to a forecasted rain event and materials should be covered and/or bermed. Material Use WM-2 November 2009 California Stormwater BMP Handbook 4 of 4 Construction www.casqa.org Provide containment for material use areas such as masons’areas or paint mixing/preparation areas to prevent materials/pollutants from entering stormwater. Costs All of the above are low cost measures. Inspection and Maintenance Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities. BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Ensure employees and subcontractors throughout the job are using appropriate practices. References Blueprint for a Clean Bay: Best Management Practices to Prevent Stormwater Pollution from Construction Related Activities; Santa Clara Valley Nonpoint Source Pollution Control Program, 1995. Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance, Working Group Working Paper; USEPA, April 1992. Comments on Risk Assessments Risk Reduction Options for Cypermethrin: Docket No. OPP– 2005–0293; California Stormwater Quality Association (CASQA) letter to USEPA, 2006.Environmental Hazard and General Labeling for Pyrethroid Non-Agricultural Outdoor Products, EPA-HQ-OPP-2008-0331-0021; USEPA, 2008. Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003. Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992. Stockpile Management WM-3 July 2012 California Stormwater BMP Handbook 1 of 3 Construction www.casqa.org Description and Purpose Stockpile management procedures and practices are designed to reduce or eliminate air and stormwater pollution from stockpiles of soil, soil amendments, sand, paving materials such as portland cement concrete (PCC) rubble, asphalt concrete (AC), asphalt concrete rubble, aggregate base, aggregate sub base or pre-mixed aggregate, asphalt minder (so called “cold mix” asphalt), and pressure treated wood. Suitable Applications Implement in all projects that stockpile soil and other loose materials. Limitations Plastic sheeting as a stockpile protection is temporary and hard to manage in windy conditions. Where plastic is used, consider use of plastic tarps with nylon reinforcement which may be more durable than standard sheeting. Plastic sheeting can increase runoff volume due to lack of infiltration and potentially cause perimeter control failure. Plastic sheeting breaks down faster in sunlight. The use of Plastic materials and photodegradable plastics should be avoided. Implementation Protection of stockpiles is a year-round requirement. To properly manage stockpiles: Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Category Secondary Category Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Stockpile Management WM-3 July 2012 California Stormwater BMP Handbook 2 of 3 Construction www.casqa.org On larger sites, a minimum of 50 ft separation from concentrated flows of stormwater, drainage courses, and inlets is recommended. After 14 days of inactivity, a stockpile is non-active and requires further protection described below. All stockpiles are required to be protected as non-active stockpiles immediately if they are not scheduled to be used within 14 days. Protect all stockpiles from stormwater runon using temporary perimeter sediment barriers such as compost berms (SE-13),temporary silt dikes (SE-12), fiber rolls (SE-5), silt fences (SE-1), sandbags (SE-8), gravel bags (SE-6),or biofilter bags (SE-14).Refer to the individual fact sheet for each of these controls for installation information. Implement wind erosion control practices as appropriate on all stockpiled material. For specific information, see WE-1, Wind Erosion Control. Manage stockpiles of contaminated soil in accordance with WM-7, Contaminated Soil Management. Place bagged materials on pallets and under cover. Ensure that stockpile coverings are installed securely to protect from wind and rain. Some plastic covers withstand weather and sunlight better than others.Select cover materials or methods based on anticipated duration of use. Protection of Non-Active Stockpiles A stockpile is considered non-active if it either is not used for 14 days or if it is scheduled not to be used for 14 days or more. Stockpiles need to be protected immediately if they are not scheduled to be used within 14 days. Non-active stockpiles of the identified materials should be protected as follows: Soil stockpiles Soil stockpiles should be covered or protected with soil stabilization measures and a temporary perimeter sediment barrier at all times. Temporary vegetation should be considered for topsoil piles that will be stockpiled for extended periods. Stockpiles of Portland cement concrete rubble, asphalt concrete, asphalt concrete rubble, aggregate base, or aggregate sub base Stockpiles should be covered and protected with a temporary perimeter sediment barrier at all times. Stockpiles of “cold mix” Cold mix stockpiles should be placed on and covered with plastic sheeting or comparable material at all times and surrounded by a berm. Stockpiles of fly ash, stucco, hydrated lime Stockpile Management WM-3 July 2012 California Stormwater BMP Handbook 3 of 3 Construction www.casqa.org Stockpiles of materials that may raise the pH of runoff (i.e., basic materials)should be covered with plastic and surrounded by a berm. Stockpiles/Storage of wood (Pressure treated with chromated copper arsenate or ammoniacal copper zinc arsenate Treated wood should be covered with plastic sheeting or comparable material at all times and surrounded by a berm. Protection of Active Stockpiles A stockpile is active when it is being used or is scheduled to be used within 14 days of the previous use. Active stockpiles of the identified materials should be protected as follows: All stockpiles should be covered and protected with a temporary linear sediment barrier prior to the onset of precipitation. Stockpiles of “cold mix” and treated wood, and basic materials should be placed on and covered with plastic sheeting or comparable material and surrounded by a berm prior to the onset of precipitation. The downstream perimeter of an active stockpile should be protected with a linear sediment barrier or berm and runoff should be diverted around or away from the stockpile on the upstream perimeter. Costs For cost information associated with stockpile protection refer to the individual erosion or sediment control BMP fact sheet considered for implementation (For example, refer to SE-1 Silt Fence for installation of silt fence around the perimeter of a stockpile.) Inspection and Maintenance Stockpiles must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. It may be necessary to inspect stockpiles covered with plastic sheeting more frequently during certain conditions (for example, high winds or extreme heat). Repair and/or replace perimeter controls and covers as needed to keep them functioning properly. Sediment shall be removed when it reaches one-third of the barrier height. References Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003. Spill Prevention and Control WM-4 January 2011 California Stormwater BMP Handbook 1 of 6 Construction www.casqa.org Description and Purpose Prevent or reduce the discharge of pollutants to drainage systems or watercourses from leaks and spills by reducing the chance for spills, stopping the source of spills, containing and cleaning up spills, properly disposing of spill materials, and training employees. This best management practice covers only spill prevention and control. However, WM-1, Materials Delivery and Storage, and WM-2, Material Use, also contain useful information, particularly on spill prevention. For information on wastes, see the waste management BMPs in this section. Suitable Applications This BMP is suitable for all construction projects. Spill control procedures are implemented anytime chemicals or hazardous substances are stored on the construction site, including the following materials: Soil stabilizers/binders Dust palliatives Herbicides Growth inhibitors Fertilizers Deicing/anti-icing chemicals Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Spill Prevention and Control WM-4 January 2011 California Stormwater BMP Handbook 2 of 6 Construction www.casqa.org Fuels Lubricants Other petroleum distillates Limitations In some cases it may be necessary to use a private spill cleanup company. This BMP applies to spills caused by the contractor and subcontractors. Procedures and practices presented in this BMP are general. Contractor should identify appropriate practices for the specific materials used or stored onsite Implementation The following steps will help reduce the stormwater impacts of leaks and spills: Education Be aware that different materials pollute in different amounts. Make sure that each employee knows what a “significant spill” is for each material they use, and what is the appropriate response for “significant” and “insignificant” spills. Educate employees and subcontractors on potential dangers to humans and the environment from spills and leaks. Hold regular meetings to discuss and reinforce appropriate disposal procedures (incorporate into regular safety meetings). Establish a continuing education program to indoctrinate new employees. Have contractor’s superintendent or representative oversee and enforce proper spill prevention and control measures. General Measures To the extent that the work can be accomplished safely, spills of oil, petroleum products, substances listed under 40 CFR parts 110,117, and 302, and sanitary and septic wastes should be contained and cleaned up immediately. Store hazardous materials and wastes in covered containers and protect from vandalism. Place a stockpile of spill cleanup materials where it will be readily accessible. Train employees in spill prevention and cleanup. Designate responsible individuals to oversee and enforce control measures. Spills should be covered and protected from stormwater runon during rainfall to the extent that it doesn’t compromise clean up activities. Do not bury or wash spills with water. Spill Prevention and Control WM-4 January 2011 California Stormwater BMP Handbook 3 of 6 Construction www.casqa.org Store and dispose of used clean up materials, contaminated materials, and recovered spill material that is no longer suitable for the intended purpose in conformance with the provisions in applicable BMPs. Do not allow water used for cleaning and decontamination to enter storm drains or watercourses. Collect and dispose of contaminated water in accordance with WM-10, Liquid Waste Management. Contain water overflow or minor water spillage and do not allow it to discharge into drainage facilities or watercourses. Place proper storage, cleanup, and spill reporting instructions for hazardous materials stored or used on the project site in an open, conspicuous, and accessible location. Keep waste storage areas clean, well organized, and equipped with ample cleanup supplies as appropriate for the materials being stored. Perimeter controls, containment structures, covers, and liners should be repaired or replaced as needed to maintain proper function. Cleanup Clean up leaks and spills immediately. Use a rag for small spills on paved surfaces, a damp mop for general cleanup, and absorbent material for larger spills. If the spilled material is hazardous, then the used cleanup materials are also hazardous and must be sent to either a certified laundry (rags) or disposed of as hazardous waste. Never hose down or bury dry material spills. Clean up as much of the material as possible and dispose of properly. See the waste management BMPs in this section for specific information. Minor Spills Minor spills typically involve small quantities of oil, gasoline, paint, etc. which can be controlled by the first responder at the discovery of the spill. Use absorbent materials on small spills rather than hosing down or burying the spill. Absorbent materials should be promptly removed and disposed of properly. Follow the practice below for a minor spill: -Contain the spread of the spill. -Recover spilled materials. -Clean the contaminated area and properly dispose of contaminated materials. Semi-Significant Spills Semi-significant spills still can be controlled by the first responder along with the aid of other personnel such as laborers and the foreman, etc. This response may require the cessation of all other activities. Spill Prevention and Control WM-4 January 2011 California Stormwater BMP Handbook 4 of 6 Construction www.casqa.org Spills should be cleaned up immediately: -Contain spread of the spill. -Notify the project foreman immediately. -If the spill occurs on paved or impermeable surfaces, clean up using "dry" methods (absorbent materials, cat litter and/or rags). Contain the spill by encircling with absorbent materials and do not let the spill spread widely. -If the spill occurs in dirt areas, immediately contain the spill by constructing an earthen dike. Dig up and properly dispose of contaminated soil. -If the spill occurs during rain, cover spill with tarps or other material to prevent contaminating runoff. Significant/Hazardous Spills For significant or hazardous spills that cannot be controlled by personnel in the immediate vicinity, the following steps should be taken: -Notify the local emergency response by dialing 911. In addition to 911, the contractor will notify the proper county officials. It is the contractor's responsibility to have all emergency phone numbers at the construction site. -Notify the Governor's Office of Emergency Services Warning Center, (916) 845-8911. -For spills of federal reportable quantities, in conformance with the requirements in 40 CFR parts 110,119, and 302, the contractor should notify the National Response Center at (800) 424-8802. -Notification should first be made by telephone and followed up with a written report. -The services of a spills contractor or a Haz-Mat team should be obtained immediately. Construction personnel should not attempt to clean up until the appropriate and qualified staffs have arrived at the job site. -Other agencies which may need to be consulted include, but are not limited to, the Fire Department, the Public Works Department, the Coast Guard, the Highway Patrol, the City/County Police Department, Department of Toxic Substances, California Division of Oil and Gas, Cal/OSHA, etc. Reporting Report significant spills to local agencies, such as the Fire Department; they can assist in cleanup. Federal regulations require that any significant oil spill into a water body or onto an adjoining shoreline be reported to the National Response Center (NRC) at 800-424-8802 (24 hours). Use the following measures related to specific activities: Spill Prevention and Control WM-4 January 2011 California Stormwater BMP Handbook 5 of 6 Construction www.casqa.org Vehicle and Equipment Maintenance If maintenance must occur onsite, use a designated area and a secondary containment, located away from drainage courses, to prevent the runon of stormwater and the runoff of spills. Regularly inspect onsite vehicles and equipment for leaks and repair immediately Check incoming vehicles and equipment (including delivery trucks, and employee and subcontractor vehicles) for leaking oil and fluids. Do not allow leaking vehicles or equipment onsite. Always use secondary containment, such as a drain pan or drop cloth, to catch spills or leaks when removing or changing fluids. Place drip pans or absorbent materials under paving equipment when not in use. Use absorbent materials on small spills rather than hosing down or burying the spill. Remove the absorbent materials promptly and dispose of properly. Promptly transfer used fluids to the proper waste or recycling drums. Don’t leave full drip pans or other open containers lying around Oil filters disposed of in trashcans or dumpsters can leak oil and pollute stormwater. Place the oil filter in a funnel over a waste oil-recycling drum to drain excess oil before disposal. Oil filters can also be recycled. Ask the oil supplier or recycler about recycling oil filters. Store cracked batteries in a non-leaking secondary container. Do this with all cracked batteries even if you think all the acid has drained out. If you drop a battery, treat it as if it is cracked. Put it into the containment area until you are sure it is not leaking. Vehicle and Equipment Fueling If fueling must occur onsite, use designate areas, located away from drainage courses, to prevent the runon of stormwater and the runoff of spills. Discourage “topping off” of fuel tanks. Always use secondary containment, such as a drain pan, when fueling to catch spills/ leaks. Costs Prevention of leaks and spills is inexpensive. Treatment and/ or disposal of contaminated soil or water can be quite expensive. Inspection and Maintenance Inspect and verify that activity–based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Spill Prevention and Control WM-4 January 2011 California Stormwater BMP Handbook 6 of 6 Construction www.casqa.org Inspect BMPs subject to non-stormwater discharge daily while non-stormwater discharges occur. Keep ample supplies of spill control and cleanup materials onsite, near storage, unloading, and maintenance areas. Update your spill prevention and control plan and stock cleanup materials as changes occur in the types of chemicals onsite. References Blueprint for a Clean Bay: Best Management Practices to Prevent Stormwater Pollution from Construction Related Activities; Santa Clara Valley Nonpoint Source Pollution Control Program, 1995. Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992. Solid Waste Management WM-5 January 2011 California Stormwater BMP Handbook 1 of 4 Construction www.casqa.org Description and Purpose Solid waste management procedures and practices are designed to prevent or reduce the discharge of pollutants to stormwater from solid or construction waste by providing designated waste collection areas and containers, arranging for regular disposal, and training employees and subcontractors. Suitable Applications This BMP is suitable for construction sites where the following wastes are generated or stored: Solid waste generated from trees and shrubs removed during land clearing, demolition of existing structures (rubble), and building construction Packaging materials including wood, paper, and plastic Scrap or surplus building materials including scrap metals, rubber, plastic, glass pieces,and masonry products Domestic wastes including food containers such as beverage cans, coffee cups, paper bags, plastic wrappers, and cigarettes Construction wastes including brick, mortar, timber, steel and metal scraps, pipe and electrical cuttings, non- hazardous equipment parts, styrofoam and other materials used to transport and package construction materials Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Solid Waste Management WM-5 January 2011 California Stormwater BMP Handbook 2 of 4 Construction www.casqa.org Highway planting wastes, including vegetative material, plant containers, and packaging materials Limitations Temporary stockpiling of certain construction wastes may not necessitate stringent drainage related controls during the non-rainy season or in desert areas with low rainfall. Implementation The following steps will help keep a clean site and reduce stormwater pollution: Select designated waste collection areas onsite. Inform trash-hauling contractors that you will accept only watertight dumpsters for onsite use. Inspect dumpsters for leaks and repair any dumpster that is not watertight. Locate containers in a covered area or in a secondary containment. Provide an adequate number of containers with lids or covers that can be placed over the container to keep rain out or to prevent loss of wastes when it is windy. Cover waste containers at the end of each work day and when it is raining. Plan for additional containers and more frequent pickup during the demolition phase of construction. Collect site trash daily, especially during rainy and windy conditions. Remove this solid waste promptly since erosion and sediment control devices tend to collect litter. Make sure that toxic liquid wastes (used oils, solvents, and paints) and chemicals (acids, pesticides, additives, curing compounds) are not disposed of in dumpsters designated for construction debris. Do not hose out dumpsters on the construction site. Leave dumpster cleaning to the trash hauling contractor. Arrange for regular waste collection before containers overflow. Clean up immediately if a container does spill. Make sure that construction waste is collected, removed, and disposed of only at authorized disposal areas. Education Have the contractor’s superintendent or representative oversee and enforce proper solid waste management procedures and practices. Instruct employees and subcontractors on identification of solid waste and hazardous waste. Educate employees and subcontractors on solid waste storage and disposal procedures. Solid Waste Management WM-5 January 2011 California Stormwater BMP Handbook 3 of 4 Construction www.casqa.org Hold regular meetings to discuss and reinforce disposal procedures (incorporate into regular safety meetings). Require that employees and subcontractors follow solid waste handling and storage procedures. Prohibit littering by employees, subcontractors, and visitors. Minimize production of solid waste materials wherever possible. Collection, Storage, and Disposal Littering on the project site should be prohibited. To prevent clogging of the storm drainage system, litter and debris removal from drainage grates, trash racks, and ditch lines should be a priority. Trash receptacles should be provided in the contractor’s yard, field trailer areas, and at locations where workers congregate for lunch and break periods. Litter from work areas within the construction limits of the project site should be collected and placed in watertight dumpsters at least weekly, regardless of whether the litter was generated by the contractor, the public, or others. Collected litter and debris should not be placed in or next to drain inlets, stormwater drainage systems, or watercourses. Dumpsters of sufficient size and number should be provided to contain the solid waste generated by the project. Full dumpsters should be removed from the project site and the contents should be disposed of by the trash hauling contractor. Construction debris and waste should be removed from the site biweekly or more frequently as needed. Construction material visible to the public should be stored or stacked in an orderly manner. Stormwater runon should be prevented from contacting stored solid waste through the use of berms, dikes, or other temporary diversion structures or through the use of measures to elevate waste from site surfaces. Solid waste storage areas should be located at least 50 ft from drainage facilities and watercourses and should not be located in areas prone to flooding or ponding. Except during fair weather, construction and highway planting waste not stored in watertight dumpsters should be securely covered from wind and rain by covering the waste with tarps or plastic. Segregate potentially hazardous waste from non-hazardous construction site waste. Make sure that toxic liquid wastes (used oils, solvents, and paints) and chemicals (acids, pesticides, additives, curing compounds) are not disposed of in dumpsters designated for construction debris. Solid Waste Management WM-5 January 2011 California Stormwater BMP Handbook 4 of 4 Construction www.casqa.org For disposal of hazardous waste, see WM-6, Hazardous Waste Management. Have hazardous waste hauled to an appropriate disposal and/or recycling facility. Salvage or recycle useful vegetation debris, packaging and surplus building materials when practical. For example, trees and shrubs from land clearing can be used as a brush barrier, or converted into wood chips, then used as mulch on graded areas. Wood pallets, cardboard boxes, and construction scraps can also be recycled. Costs All of the above are low cost measures. Inspection and Maintenance Inspect and verify that activity–based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Inspect BMPs subject to non-stormwater discharge daily while non-stormwater discharges occur Inspect construction waste area regularly. Arrange for regular waste collection. References Processes, Procedures and Methods to Control Pollution Resulting from All Construction Activity, 430/9-73-007, USEPA, 1973. Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992. Hazardous Waste Management WM-6 January 2011 California Stormwater BMP Handbook 1 of 6 Construction www.casqa.org Description and Purpose Prevent or reduce the discharge of pollutants to stormwater from hazardous waste through proper material use, waste disposal, and training of employees and subcontractors. Suitable Applications This best management practice (BMP) applies to all construction projects. Hazardous waste management practices are implemented on construction projects that generate waste from the use of: Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. -Petroleum Products -Asphalt Products -Concrete Curing Compounds -Pesticides -Palliatives -Acids -Septic Wastes -Paints -Stains -Solvents -Wood Preservatives -Roofing Tar -Any materials deemed a hazardous waste in California, Title 22 Division 4.5, or listed in 40 CFR Parts 110, 117, 261, or 302 Hazardous Waste Management WM-6 January 2011 California Stormwater BMP Handbook 2 of 6 Construction www.casqa.org In addition, sites with existing structures may contain wastes, which must be disposed of in accordance with federal, state, and local regulations. These wastes include: Sandblasting grit mixed with lead-, cadmium-, or chromium-based paints Asbestos PCBs (particularly in older transformers) Limitations Hazardous waste that cannot be reused or recycled must be disposed of by a licensed hazardous waste hauler. Nothing in this BMP relieves the contractor from responsibility for compliance with federal, state, and local laws regarding storage, handling, transportation, and disposal of hazardous wastes. This BMP does not cover aerially deposited lead (ADL) soils. For ADL soils refer to WM-7, Contaminated Soil Management. Implementation The following steps will help reduce stormwater pollution from hazardous wastes: Material Use Wastes should be stored in sealed containers constructed of a suitable material and should be labeled as required by Title 22 CCR, Division 4.5 and 49 CFR Parts 172, 173, 178, and 179. All hazardous waste should be stored, transported, and disposed as required in Title 22 CCR, Division 4.5 and 49 CFR 261-263. Waste containers should be stored in temporary containment facilities that should comply with the following requirements: -Temporary containment facility should provide for a spill containment volume equal to 1.5 times the volume of all containers able to contain precipitation from a 25 year storm event, plus the greater of 10% of the aggregate volume of all containers or 100% of the capacity of the largest tank within its boundary, whichever is greater. -Temporary containment facility should be impervious to the materials stored there for a minimum contact time of 72 hours. -Temporary containment facilities should be maintained free of accumulated rainwater and spills. In the event of spills or leaks, accumulated rainwater and spills should be placed into drums after each rainfall. These liquids should be handled as a hazardous waste unless testing determines them to be non-hazardous. Non-hazardous liquids should be sent to an approved disposal site. -Sufficient separation should be provided between stored containers to allow for spill cleanup and emergency response access. Hazardous Waste Management WM-6 January 2011 California Stormwater BMP Handbook 3 of 6 Construction www.casqa.org -Incompatible materials, such as chlorine and ammonia, should not be stored in the same temporary containment facility. -Throughout the rainy season, temporary containment facilities should be covered during non-working days, and prior to rain events. Covered facilities may include use of plastic tarps for small facilities or constructed roofs with overhangs. Drums should not be overfilled and wastes should not be mixed. Unless watertight, containers of dry waste should be stored on pallets. Do not over-apply herbicides and pesticides. Prepare only the amount needed. Follow the recommended usage instructions. Over application is expensive and environmentally harmful. Apply surface dressings in several smaller applications, as opposed to one large application. Allow time for infiltration and avoid excess material being carried offsite by runoff. Do not apply these chemicals just before it rains. People applying pesticides must be certified in accordance with federal and state regulations. Paint brushes and equipment for water and oil based paints should be cleaned within a contained area and should not be allowed to contaminate site soils, watercourses, or drainage systems. Waste paints, thinners, solvents, residues, and sludges that cannot be recycled or reused should be disposed of as hazardous waste. When thoroughly dry, latex paint and paint cans, used brushes, rags, absorbent materials, and drop cloths should be disposed of as solid waste. Do not clean out brushes or rinse paint containers into the dirt, street, gutter, storm drain, or stream. “Paint out” brushes as much as possible. Rinse water-based paints to the sanitary sewer. Filter and reuse thinners and solvents. Dispose of excess oil-based paints and sludge as hazardous waste. The following actions should be taken with respect to temporary contaminant: -Ensure that adequate hazardous waste storage volume is available. -Ensure that hazardous waste collection containers are conveniently located. -Designate hazardous waste storage areas onsite away from storm drains or watercourses and away from moving vehicles and equipment to prevent accidental spills. -Minimize production or generation of hazardous materials and hazardous waste on the job site. -Use containment berms in fueling and maintenance areas and where the potential for spills is high. -Segregate potentially hazardous waste from non-hazardous construction site debris. -Keep liquid or semi-liquid hazardous waste in appropriate containers (closed drums or similar) and under cover. Hazardous Waste Management WM-6 January 2011 California Stormwater BMP Handbook 4 of 6 Construction www.casqa.org -Clearly label all hazardous waste containers with the waste being stored and the date of accumulation. -Place hazardous waste containers in secondary containment. -Do not allow potentially hazardous waste materials to accumulate on the ground. -Do not mix wastes. -Use all of the product before disposing of the container. -Do not remove the original product label; it contains important safety and disposal information. Waste Recycling Disposal Select designated hazardous waste collection areas onsite. Hazardous materials and wastes should be stored in covered containers and protected from vandalism. Place hazardous waste containers in secondary containment. Do not mix wastes, this can cause chemical reactions, making recycling impossible and complicating disposal. Recycle any useful materials such as used oil or water-based paint. Make sure that toxic liquid wastes (used oils, solvents, and paints) and chemicals (acids, pesticides, additives, curing compounds) are not disposed of in dumpsters designated for construction debris. Arrange for regular waste collection before containers overflow. Make sure that hazardous waste (e.g., excess oil-based paint and sludge) is collected, removed, and disposed of only at authorized disposal areas. Disposal Procedures Waste should be disposed of by a licensed hazardous waste transporter at an authorized and licensed disposal facility or recycling facility utilizing properly completed Uniform Hazardous Waste Manifest forms. A Department of Health Services certified laboratory should sample waste to determine the appropriate disposal facility. Properly dispose of rainwater in secondary containment that may have mixed with hazardous waste. Attention is directed to "Hazardous Material", "Contaminated Material", and "Aerially Deposited Lead" of the contract documents regarding the handling and disposal of hazardous materials. Hazardous Waste Management WM-6 January 2011 California Stormwater BMP Handbook 5 of 6 Construction www.casqa.org Education Educate employees and subcontractors on hazardous waste storage and disposal procedures. Educate employees and subcontractors on potential dangers to humans and the environment from hazardous wastes. Instruct employees and subcontractors on safety procedures for common construction site hazardous wastes. Instruct employees and subcontractors in identification of hazardous and solid waste. Hold regular meetings to discuss and reinforce hazardous waste management procedures (incorporate into regular safety meetings). The contractor’s superintendent or representative should oversee and enforce proper hazardous waste management procedures and practices. Make sure that hazardous waste is collected, removed, and disposed of only at authorized disposal areas. Warning signs should be placed in areas recently treated with chemicals. Place a stockpile of spill cleanup materials where it will be readily accessible. If a container does spill, clean up immediately. Costs All of the above are low cost measures. Inspection and Maintenance Inspect and verify that activity–based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way,inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.. Inspect BMPs subject to non-stormwater discharge daily while non-stormwater discharges occur Hazardous waste should be regularly collected. A foreman or construction supervisor should monitor onsite hazardous waste storage and disposal procedures. Waste storage areas should be kept clean, well organized, and equipped with ample cleanup supplies as appropriate for the materials being stored. Perimeter controls, containment structures, covers, and liners should be repaired or replaced as needed to maintain proper function. Hazardous Waste Management WM-6 January 2011 California Stormwater BMP Handbook 6 of 6 Construction www.casqa.org Hazardous spills should be cleaned up and reported in conformance with the applicable Material Safety Data Sheet (MSDS) and the instructions posted at the project site. The National Response Center, at (800) 424-8802, should be notified of spills of federal reportable quantities in conformance with the requirements in 40 CFR parts 110, 117, and 302. Also notify the Governors Office of Emergency Services Warning Center at (916) 845- 8911. A copy of the hazardous waste manifests should be provided. References Blueprint for a Clean Bay: Best Management Practices to Prevent Stormwater Pollution from Construction Related Activities; Santa Clara Valley Nonpoint Source Pollution Control Program, 1995. Processes, Procedures and Methods to Control Pollution Resulting from All Construction Activity, 430/9-73-007, USEPA, 1973. Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992. Concrete Waste Management WM-8 July 2012 California Stormwater BMP Handbook 1 of 7 Construction www.casqa.org Description and Purpose Prevent the discharge of pollutants to stormwater from concrete waste by conducting washout onsite or offsite in a designated area, and by employee and subcontractor training. The General Permit incorporates Numeric Action Levels (NAL) for pH (see Section 2 of this handbook to determine your project’s risk level and if you are subject to these requirements). Many types of construction materials, including mortar, concrete, stucco, cement and block and their associated wastes have basic chemical properties that can raise pH levels outside of the permitted range.Additional care should be taken when managing these materials to prevent them from coming into contact with stormwater flows and raising pH to levels outside the accepted range. Suitable Applications Concrete waste management procedures and practices are implemented on construction projects where: Concrete is used as a construction material or where concrete dust and debris result from demolition activities. Slurries containing portland cement concrete (PCC) are generated, such as from saw cutting, coring, grinding, grooving, and hydro-concrete demolition. Concrete trucks and other concrete-coated equipment are washed onsite. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Category Secondary Category Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Concrete Waste Management WM-8 July 2012 California Stormwater BMP Handbook 2 of 7 Construction www.casqa.org Mortar-mixing stations exist. Stucco mixing and spraying. See also NS-8, Vehicle and Equipment Cleaning. Limitations Offsite washout of concrete wastes may not always be possible. Multiple washouts may be needed to assure adequate capacity and to allow for evaporation. Implementation The following steps will help reduce stormwater pollution from concrete wastes: Incorporate requirements for concrete waste management into material supplier and subcontractor agreements. Store dry and wet materials under cover, away from drainage areas.Refer to WM-1, Material Delivery and Storage for more information. Avoid mixing excess amounts of concrete. Perform washout of concrete trucks in designated areas only, where washout will not reach stormwater. Do not wash out concrete trucks into storm drains, open ditches, streets,streams or onto the ground.Trucks should always be washed out into designated facilities. Do not allow excess concrete to be dumped onsite, except in designated areas. For onsite washout: -On larger sites, it is recommended to locate washout areas at least 50 feet from storm drains, open ditches, or water bodies. Do not allow runoff from this area by constructing a temporary pit or bermed area large enough for liquid and solid waste. -Washout wastes into the temporary washout where the concrete can set, be broken up, and then disposed properly. -Washouts shall be implemented in a manner that prevents leaching to underlying soils. Washout containers must be water tight and washouts on or in the ground must be lined with a suitable impervious liner, typically a plastic type material. Do not wash sweepings from exposed aggregate concrete into the street or storm drain. Collect and return sweepings to aggregate base stockpile or dispose in the trash. See typical concrete washout installation details at the end of this fact sheet. Education Educate employees, subcontractors, and suppliers on the concrete waste management techniques described herein. Concrete Waste Management WM-8 July 2012 California Stormwater BMP Handbook 3 of 7 Construction www.casqa.org Arrange for contractor’s superintendent or representative to oversee and enforce concrete waste management procedures. Discuss the concrete management techniques described in this BMP (such as handling of concrete waste and washout) with the ready-mix concrete supplier before any deliveries are made. Concrete Demolition Wastes Stockpile concrete demolition waste in accordance with BMP WM-3, Stockpile Management. Dispose of or recycle hardened concrete waste in accordance with applicable federal, state or local regulations. Concrete Slurry Wastes PCC and AC waste should not be allowed to enter storm drains or watercourses. PCC and AC waste should be collected and disposed of or placed in a temporary concrete washout facility (as described in Onsite Temporary Concrete Washout Facility, Concrete Transit Truck Washout Procedures, below). A foreman or construction supervisor should monitor onsite concrete working tasks, such as saw cutting, coring, grinding and grooving to ensure proper methods are implemented. Saw-cut concrete slurry should not be allowed to enter storm drains or watercourses. Residue from grinding operations should be picked up by means of a vacuum attachment to the grinding machine or by sweeping. Saw cutting residue should not be allowed to flow across the pavement and should not be left on the surface of the pavement. See also NS-3, Paving and Grinding Operations; and WM-10, Liquid Waste Management. Concrete slurry residue should be disposed in a temporary washout facility (as described in Onsite Temporary Concrete Washout Facility, Concrete Transit Truck Washout Procedures, below) and allowed to dry. Dispose of dry slurry residue in accordance with WM-5, Solid Waste Management. Onsite Temporary Concrete Washout Facility, Transit Truck Washout Procedures Temporary concrete washout facilities should be located a minimum of 50 ft from storm drain inlets, open drainage facilities, and watercourses. Each facility should be located away from construction traffic or access areas to prevent disturbance or tracking. A sign should be installed adjacent to each washout facility to inform concrete equipment operators to utilize the proper facilities. Temporary concrete washout facilities should be constructed above grade or below grade at the option of the contractor. Temporary concrete washout facilities should be constructed and maintained in sufficient quantity and size to contain all liquid and concrete waste generated by washout operations. Concrete Waste Management WM-8 July 2012 California Stormwater BMP Handbook 4 of 7 Construction www.casqa.org Temporary washout facilities should have a temporary pit or bermed areas of sufficient volume to completely contain all liquid and waste concrete materials generated during washout procedures. Temporary washout facilities should be lined to prevent discharge to the underlying ground or surrounding area. Washout of concrete trucks should be performed in designated areas only. Only concrete from mixer truck chutes should be washed into concrete wash out. Concrete washout from concrete pumper bins can be washed into concrete pumper trucks and discharged into designated washout area or properly disposed of or recycled offsite. Once concrete wastes are washed into the designated area and allowed to harden, the concrete should be broken up, removed, and disposed of per WM-5, Solid Waste Management. Dispose of or recycle hardened concrete on a regular basis. Temporary Concrete Washout Facility (Type Above Grade) -Temporary concrete washout facility (type above grade) should be constructed as shown on the details at the end of this BMP, with a recommended minimum length and minimum width of 10 ft; however, smaller sites or jobs may only need a smaller washout facility. With any washout,always maintain a sufficient quantity and volume to contain all liquid and concrete waste generated by washout operations. -Materials used to construct the washout area should conform to the provisions detailed in their respective BMPs (e.g.,SE-8 Sandbag Barrier). -Plastic lining material should be a minimum of 10 mil in polyethylene sheeting and should be free of holes, tears, or other defects that compromise the impermeability of the material. -Alternatively, portable removable containers can be used as above grade concrete washouts. Also called a “roll-off”; this concrete washout facility should be properly sealed to prevent leakage, and should be removed from the site and replaced when the container reaches 75% capacity. Temporary Concrete Washout Facility (Type Below Grade) -Temporary concrete washout facilities (type below grade) should be constructed as shown on the details at the end of this BMP, with a recommended minimum length and minimum width of 10 ft. The quantity and volume should be sufficient to contain all liquid and concrete waste generated by washout operations. -Lath and flagging should be commercial type. -Plastic lining material should be a minimum of 10 mil polyethylene sheeting and should be free of holes, tears, or other defects that compromise the impermeability of the material. Concrete Waste Management WM-8 July 2012 California Stormwater BMP Handbook 5 of 7 Construction www.casqa.org -The base of a washout facility should be free of rock or debris that may damage a plastic liner. Removal of Temporary Concrete Washout Facilities When temporary concrete washout facilities are no longer required for the work, the hardened concrete should be removed and properly disposed or recycled in accordance with federal, state or local regulations. Materials used to construct temporary concrete washout facilities should be removed from the site of the work and properly disposed or recycled in accordance with federal, state or local regulations.. Holes, depressions or other ground disturbance caused by the removal of the temporary concrete washout facilities should be backfilled and repaired. Costs All of the above are low cost measures.Roll-0ff concrete washout facilities can be more costly than other measures due to removal and replacement; however, provide a cleaner alternative to traditional washouts.The type of washout facility, size, and availability of materials will determine the cost of the washout. Inspection and Maintenance BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Temporary concrete washout facilities should be maintained to provide adequate holding capacity with a minimum freeboard of 4 in. for above grade facilities and 12 in. for below grade facilities. Maintaining temporary concrete washout facilities should include removing and disposing of hardened concrete and returning the facilities to a functional condition. Hardened concrete materials should be removed and properly disposed or recycled in accordance with federal, state or local regulations. Washout facilities must be cleaned, or new facilities must be constructed and ready for use once the washout is 75% full. Inspect washout facilities for damage (e.g. torn liner, evidence of leaks, signage, etc.). Repair all identified damage. References Blueprint for a Clean Bay: Best Management Practices to Prevent Stormwater Pollution from Construction Related Activities; Santa Clara Valley Nonpoint Source Pollution Control Program, 1995. Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000, Updated March 2003. Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992. Concrete Waste Management WM-8 July 2012 California Stormwater BMP Handbook 6 of 7 Construction www.casqa.org Concrete Waste Management WM-8 July 2012 California Stormwater BMP Handbook 7 of 7 Construction www.casqa.org Sanitary/Septic Waste Management WM-9 November 2009 California Stormwater BMP Handbook 1 of 3 Construction www.casqa.org Description and Purpose Proper sanitary and septic waste management prevent the discharge of pollutants to stormwater from sanitary and septic waste by providing convenient, well-maintained facilities,and arranging for regular service and disposal. Suitable Applications Sanitary septic waste management practices are suitable for use at all construction sites that use temporary or portable sanitary and septic waste systems. Limitations None identified. Implementation Sanitary or septic wastes should be treated or disposed of in accordance with state and local requirements. In many cases, one contract with a local facility supplier will be all that it takes to make sure sanitary wastes are properly disposed. Storage and Disposal Procedures Temporary sanitary facilities should be located away from drainage facilities, watercourses, and from traffic circulation. If site conditions allow, place portable facilities a minimum of 50 feet from drainage conveyances and traffic areas. When subjected to high winds or risk of high winds, temporary sanitary facilities should be secured to prevent overturning. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Category Secondary Category Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Sanitary/Septic Waste Management WM-9 November 2009 California Stormwater BMP Handbook 2 of 3 Construction www.casqa.org Temporary sanitary facilities must be equipped with containment to prevent discharge of pollutants to the stormwater drainage system of the receiving water. Consider safety as well as environmental implications before placing temporary sanitary facilities. Wastewater should not be discharged or buried within the project site. Sanitary and septic systems that discharge directly into sanitary sewer systems, where permissible, should comply with the local health agency, city, county, and sewer district requirements. Only reputable, licensed sanitary and septic waste haulers should be used. Sanitary facilities should be located in a convenient location. Temporary septic systems should treat wastes to appropriate levels before discharging. If using an onsite disposal system (OSDS), such as a septic system, local health agency requirements must be followed. Temporary sanitary facilities that discharge to the sanitary sewer system should be properly connected to avoid illicit discharges. Sanitary and septic facilities should be maintained in good working order by a licensed service. Regular waste collection by a licensed hauler should be arranged before facilities overflow. If a spill does occur from a temporary sanitary facility, follow federal, state and local regulations for containment and clean-up. Education Educate employees, subcontractors, and suppliers on sanitary and septic waste storage and disposal procedures. Educate employees, subcontractors, and suppliers of potential dangers to humans and the environment from sanitary and septic wastes. Instruct employees, subcontractors, and suppliers in identification of sanitary and septic waste. Hold regular meetings to discuss and reinforce the use of sanitary facilities (incorporate into regular safety meetings). Establish a continuing education program to indoctrinate new employees. Costs All of the above are low cost measures. Sanitary/Septic Waste Management WM-9 November 2009 California Stormwater BMP Handbook 3 of 3 Construction www.casqa.org Inspection and Maintenance BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Arrange for regular waste collection. If high winds are expected, portable sanitary facilities must be secured with spikes or weighed down to prevent over turning. If spills or leaks from sanitary or septic facilities occur that are not contained and discharge from the site, non-visible sampling of site discharge may be required. Refer to the General Permit or to your project specific Construction Site Monitoring Plan to determine if and where sampling is required. References Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003. Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992. Liquid Waste Management WM-10 November 2009 California Stormwater BMP Handbook 1 of 4 Construction www.casqa.org Description and Purpose Liquid waste management includes procedures and practices to prevent discharge of pollutants to the storm drain system or to watercourses as a result of the creation, collection, and disposal of non-hazardous liquid wastes. Suitable Applications Liquid waste management is applicable to construction projects that generate any of the following non-hazardous by-products, residuals, or wastes: Drilling slurries and drilling fluids Grease-free and oil-free wastewater and rinse water Dredgings Other non-stormwater liquid discharges not permitted by separate permits Limitations Disposal of some liquid wastes may be subject to specific laws and regulations or to requirements of other permits secured for the construction project (e.g., NPDES permits, Army Corps permits, Coastal Commission permits, etc.). Liquid waste management does not apply to dewatering operations (NS-2 Dewatering Operations), solid waste management (WM-5, Solid Waste Management), hazardous wastes (WM-6, Hazardous Waste Management), or Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Liquid Waste Management WM-10 November 2009 California Stormwater BMP Handbook 2 of 4 Construction www.casqa.org concrete slurry residue (WM-8, Concrete Waste Management). Typical permitted non-stormwater discharges can include: water line flushing; landscape irrigation; diverted stream flows; rising ground waters; uncontaminated pumped ground water; discharges from potable water sources; foundation drains; irrigation water; springs; water from crawl space pumps; footing drains; lawn watering; flows from riparian habitats and wetlands; and discharges or flows from emergency fire fighting activities. Implementation General Practices Instruct employees and subcontractors how to safely differentiate between non-hazardous liquid waste and potential or known hazardous liquid waste. Instruct employees, subcontractors, and suppliers that it is unacceptable for any liquid waste to enter any storm drainage device, waterway, or receiving water. Educate employees and subcontractors on liquid waste generating activities and liquid waste storage and disposal procedures. Hold regular meetings to discuss and reinforce disposal procedures (incorporate into regular safety meetings). Verify which non-stormwater discharges are permitted by the statewide NPDES permit; different regions might have different requirements not outlined in this permit. Apply NS-8, Vehicle and Equipment Cleaning for managing wash water and rinse water from vehicle and equipment cleaning operations. Containing Liquid Wastes Drilling residue and drilling fluids should not be allowed to enter storm drains and watercourses and should be disposed of. If an appropriate location is available, drilling residue and drilling fluids that are exempt under Title 23, CCR § 2511(g) may be dried by infiltration and evaporation in a containment facility constructed in conformance with the provisions concerning the Temporary Concrete Washout Facilities detailed in WM-8, Concrete Waste Management. Liquid wastes generated as part of an operational procedure, such as water-laden dredged material and drilling mud, should be contained and not allowed to flow into drainage channels or receiving waters prior to treatment. Liquid wastes should be contained in a controlled area such as a holding pit, sediment basin, roll-off bin, or portable tank. Containment devices must be structurally sound and leak free. Containment devices must be of sufficient quantity or volume to completely contain the liquid wastes generated. Liquid Waste Management WM-10 November 2009 California Stormwater BMP Handbook 3 of 4 Construction www.casqa.org Precautions should be taken to avoid spills or accidental releases of contained liquid wastes. Apply the education measures and spill response procedures outlined in WM-4, Spill Prevention and Control. Containment areas or devices should not be located where accidental release of the contained liquid can threaten health or safety or discharge to water bodies, channels, or storm drains. Capturing Liquid Wastes Capture all liquid wastes that have the potential to affect the storm drainage system (such as wash water and rinse water from cleaning walls or pavement), before they run off a surface. Do not allow liquid wastes to flow or discharge uncontrolled. Use temporary dikes or berms to intercept flows and direct them to a containment area or device for capture. Use a sediment trap (SE-3, Sediment Trap) for capturing and treating sediment laden liquid waste or capture in a containment device and allow sediment to settle. Disposing of Liquid Wastes A typical method to handle liquid waste is to dewater the contained liquid waste, using procedures such as described in NS-2, Dewatering Operations, and SE-2, Sediment Basin, and dispose of resulting solids per WM-5, Solid Waste Management. Methods of disposal for some liquid wastes may be prescribed in Water Quality Reports, NPDES permits, Environmental Impact Reports, 401 or 404 permits, and local agency discharge permits, etc. Review the SWPPP to see if disposal methods are identified. Liquid wastes, such as from dredged material, may require testing and certification whether it is hazardous or not before a disposal method can be determined. For disposal of hazardous waste, see WM-6, Hazardous Waste Management. If necessary, further treat liquid wastes prior to disposal. Treatment may include, though is not limited to, sedimentation, filtration, and chemical neutralization. Costs Prevention costs for liquid waste management are minimal. Costs increase if cleanup or fines are involved. Inspection and Maintenance Inspect and verify that activity–based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect weekly during the rainy season and of two-week intervals in the non-rainy season to verify continued BMP implementation. Inspect BMPs subject to non-stormwater discharge daily while non-stormwater discharges occur. Liquid Waste Management WM-10 November 2009 California Stormwater BMP Handbook 4 of 4 Construction www.casqa.org Remove deposited solids in containment areas and capturing devices as needed and at the completion of the task. Dispose of any solids as described in WM-5, Solid Waste Management. Inspect containment areas and capturing devices and repair as needed. References Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Water Conservation Practices NS-1 January 2011 California Stormwater BMP Handbook 1 of 2 Construction www.casqa.org Description and Purpose Water conservation practices are activities that use water during the construction of a project in a manner that avoids causing erosion and the transport of pollutants offsite.These practices can reduce or eliminate non-stormwater discharges. Suitable Applications Water conservation practices are suitable for all construction sites where water is used, including piped water, metered water, trucked water, and water from a reservoir. Limitations None identified. Implementation Keep water equipment in good working condition. Stabilize water truck filling area. Repair water leaks promptly. Washing of vehicles and equipment on the construction site is discouraged. Avoid using water to clean construction areas. If water must be used for cleaning or surface preparation, surface should be swept and vacuumed first to remove dirt. This will minimize amount of water required. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Water Conservation Practices NS-1 January 2011 California Stormwater BMP Handbook 2 of 2 Construction www.casqa.org Direct construction water runoff to areas where it can soak into the ground or be collected and reused. Authorized non-stormwater discharges to the storm drain system, channels, or receiving waters are acceptable with the implementation of appropriate BMPs. Lock water tank valves to prevent unauthorized use. Costs The cost is small to none compared to the benefits of conserving water. Inspection and Maintenance Inspect and verify that activity based BMPs are in place prior to the commencement of authorized non-stormwater discharges. Inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Inspect BMPs subject to non-stormwater discharges daily while non-stormwater discharges are occuring. Repair water equipment as needed to prevent unintended discharges. -Water trucks -Water reservoirs (water buffalos) -Irrigation systems -Hydrant connections References Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Illicit Connection/Discharge NS-6 January 2011 California Stormwater BMP Handbook 1 of 3 Construction www.casqa.org Description and Purpose Procedures and practices designed for construction contractors to recognize illicit connections or illegally dumped or discharged materials on a construction site and report incidents. Suitable Applications This best management practice (BMP) applies to all construction projects. Illicit connection/discharge and reporting is applicable anytime an illicit connection or discharge is discovered or illegally dumped material is found on the construction site. Limitations Illicit connections and illegal discharges or dumping, for the purposes of this BMP, refer to discharges and dumping caused by parties other than the contractor. If pre-existing hazardous materials or wastes are known to exist onsite, they should be identified in the SWPPP and handled as set forth in the SWPPP. Implementation Planning Review the SWPPP. Pre-existing areas of contamination should be identified and documented in the SWPPP. Inspect site before beginning the job for evidence of illicit connections, illegal dumping or discharges. Document any pre-existing conditions and notify the owner. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Illicit Connection/Discharge NS-6 January 2011 California Stormwater BMP Handbook 2 of 3 Construction www.casqa.org Inspect site regularly during project execution for evidence of illicit connections, illegal dumping or discharges. Observe site perimeter for evidence for potential of illicitly discharged or illegally dumped material, which may enter the job site. Identification of Illicit Connections and Illegal Dumping or Discharges General –unlabeled and unidentifiable material should be treated as hazardous. Solids -Look for debris, or rubbish piles. Solid waste dumping often occurs on roadways with light traffic loads or in areas not easily visible from the traveled way. Liquids -signs of illegal liquid dumping or discharge can include: -Visible signs of staining or unusual colors to the pavement or surrounding adjacent soils -Pungent odors coming from the drainage systems -Discoloration or oily substances in the water or stains and residues detained within ditches, channels or drain boxes -Abnormal water flow during the dry weather season Urban Areas -Evidence of illicit connections or illegal discharges is typically detected at storm drain outfall locations or at manholes. Signs of an illicit connection or illegal discharge can include: -Abnormal water flow during the dry weather season -Unusual flows in sub drain systems used for dewatering -Pungent odors coming from the drainage systems -Discoloration or oily substances in the water or stains and residues detained within ditches, channels or drain boxes -Excessive sediment deposits, particularly adjacent to or near active offsite construction projects Rural Areas -Illicit connections or illegal discharges involving irrigation drainage ditches are detected by visual inspections. Signs of an illicit discharge can include: -Abnormal water flow during the non-irrigation season -Non-standard junction structures -Broken concrete or other disturbances at or near junction structures Reporting Notify the owner of any illicit connections and illegal dumping or discharge incidents at the time of discovery. For illicit connections or discharges to the storm drain system, notify the local stormwater management agency. For illegal dumping, notify the local law enforcement agency. Cleanup and Removal The responsibility for cleanup and removal of illicit or illegal dumping or discharges will vary by location. Contact the local stormwater management agency for further information. Illicit Connection/Discharge NS-6 January 2011 California Stormwater BMP Handbook 3 of 3 Construction www.casqa.org Costs Costs to look for and report illicit connections and illegal discharges and dumping are low. The best way to avoid costs associated with illicit connections and illegal discharges and dumping is to keep the project perimeters secure to prevent access to the site, to observe the site for vehicles that should not be there, and to document any waste or hazardous materials that exist onsite before taking possession of the site. Inspection and Maintenance Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Inspect the site regularly to check for any illegal dumping or discharge. Prohibit employees and subcontractors from disposing of non-job related debris or materials at the construction site. Notify the owner of any illicit connections and illegal dumping or discharge incidents at the time of discovery. References Blueprint for a Clean Bay: Best Management Practices to Prevent Stormwater Pollution from Construction Related Activities; Santa Clara Valley Nonpoint Source Pollution Control Program, 1995. Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Stormwater Management for Construction Activities, Developing Pollution Prevention Plans and Best Management Practices, EPA 832-R-92005; USEPA, April 1992. Vehicle and Equipment Cleaning NS-8 January 2011 California Stormwater BMP Handbook 1 of 3 Construction www.casqa.org Description and Purpose Vehicle and equipment cleaning procedures and practices eliminate or reduce the discharge of pollutants to stormwater from vehicle and equipment cleaning operations. Procedures and practices include but are not limited to:using offsite facilities; washing in designated, contained areas only; eliminating discharges to the storm drain by infiltrating the wash water; and training employees and subcontractors in proper cleaning procedures. Suitable Applications These procedures are suitable on all construction sites where vehicle and equipment cleaning is performed. Limitations Even phosphate-free, biodegradable soaps have been shown to be toxic to fish before the soap degrades. Sending vehicles/equipment offsite should be done in conjunction with TC-1, Stabilized Construction Entrance/Exit. Implementation Other options to washing equipment onsite include contracting with either an offsite or mobile commercial washing business. These businesses may be better equipped to handle and dispose of the wash waters properly. Performing this work offsite can also be economical by eliminating the need for a separate washing operation onsite. If washing operations are to take place onsite, then: Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Vehicle and Equipment Cleaning NS-8 January 2011 California Stormwater BMP Handbook 2 of 3 Construction www.casqa.org Use phosphate-free, biodegradable soaps. Educate employees and subcontractors on pollution prevention measures. Do not permit steam cleaning onsite. Steam cleaning can generate significant pollutant concentrates. Cleaning of vehicles and equipment with soap, solvents or steam should not occur on the project site unless resulting wastes are fully contained and disposed of. Resulting wastes should not be discharged or buried, and must be captured and recycled or disposed according to the requirements of WM-10, Liquid Waste Management or WM-6, Hazardous Waste Management, depending on the waste characteristics. Minimize use of solvents. Use of diesel for vehicle and equipment cleaning is prohibited. All vehicles and equipment that regularly enter and leave the construction site must be cleaned offsite. When vehicle and equipment washing and cleaning must occur onsite, and the operation cannot be located within a structure or building equipped with appropriate disposal facilities, the outside cleaning area should have the following characteristics: -Located away from storm drain inlets, drainage facilities, or watercourses -Paved with concrete or asphalt and bermed to contain wash waters and to prevent runon and runoff -Configured with a sump to allow collection and disposal of wash water -No discharge of wash waters to storm drains or watercourses -Used only when necessary When cleaning vehicles and equipment with water: -Use as little water as possible. High-pressure sprayers may use less water than a hose and should be considered -Use positive shutoff valve to minimize water usage -Facility wash racks should discharge to a sanitary sewer, recycle system or other approved discharge system and must not discharge to the storm drainage system, watercourses, or to groundwater Costs Cleaning vehicles and equipment at an offsite facility may reduce overall costs for vehicle and equipment cleaning by eliminating the need to provide similar services onsite. When onsite cleaning is needed, the cost to establish appropriate facilities is relatively low on larger, long- duration projects, and moderate to high on small, short-duration projects. Vehicle and Equipment Cleaning NS-8 January 2011 California Stormwater BMP Handbook 3 of 3 Construction www.casqa.org Inspection and Maintenance Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Inspect BMPs subject to non-stormwater discharges daily while non-stormwater discharges occur. Inspection and maintenance is minimal, although some berm repair may be necessary. Monitor employees and subcontractors throughout the duration of the construction project to ensure appropriate practices are being implemented. Inspect sump regularly and remove liquids and sediment as needed. Prohibit employees and subcontractors from washing personal vehicles and equipment on the construction site. References Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Swisher, R.D.Surfactant Biodegradation, Marcel Decker Corporation, 1987. Vehicle and Equipment Fueling NS-9 January 2011 California Stormwater BMP Handbook 1 of 3 Construction www.casqa.org Description and Purpose Vehicle equipment fueling procedures and practices are designed to prevent fuel spills and leaks, and reduce or eliminate contamination of stormwater. This can be accomplished by using offsite facilities, fueling in designated areas only, enclosing or covering stored fuel, implementing spill controls, and training employees and subcontractors in proper fueling procedures. Suitable Applications These procedures are suitable on all construction sites where vehicle and equipment fueling takes place. Limitations Onsite vehicle and equipment fueling should only be used where it is impractical to send vehicles and equipment offsite for fueling. Sending vehicles and equipment offsite should be done in conjunction with TC-1, Stabilized Construction Entrance/ Exit. Implementation Use offsite fueling stations as much as possible. These businesses are better equipped to handle fuel and spills properly. Performing this work offsite can also be economical by eliminating the need for a separate fueling area at a site. Discourage “topping-off” of fuel tanks. Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Vehicle and Equipment Fueling NS-9 January 2011 California Stormwater BMP Handbook 2 of 3 Construction www.casqa.org Absorbent spill cleanup materials and spill kits should be available in fueling areas and on fueling trucks, and should be disposed of properly after use. Drip pans or absorbent pads should be used during vehicle and equipment fueling, unless the fueling is performed over an impermeable surface in a dedicated fueling area. Use absorbent materials on small spills. Do not hose down or bury the spill. Remove the adsorbent materials promptly and dispose of properly. Avoid mobile fueling of mobile construction equipment around the site; rather, transport the equipment to designated fueling areas. With the exception of tracked equipment such as bulldozers and large excavators, most vehicles should be able to travel to a designated area with little lost time. Train employees and subcontractors in proper fueling and cleanup procedures. When fueling must take place onsite, designate an area away from drainage courses to be used. Fueling areas should be identified in the SWPPP. Dedicated fueling areas should be protected from stormwater runon and runoff, and should be located at least 50 ft away from downstream drainage facilities and watercourses. Fueling must be performed on level-grade areas. Protect fueling areas with berms and dikes to prevent runon, runoff, and to contain spills. Nozzles used in vehicle and equipment fueling should be equipped with an automatic shutoff to control drips. Fueling operations should not be left unattended. Use vapor recovery nozzles to help control drips as well as air pollution where required by Air Quality Management Districts (AQMD). Federal, state, and local requirements should be observed for any stationary above ground storage tanks. Costs All of the above measures are low cost except for the capital costs of above ground tanks that meet all local environmental, zoning, and fire codes. Inspection and Maintenance Inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Vehicles and equipment should be inspected each day of use for leaks. Leaks should be repaired immediately or problem vehicles or equipment should be removed from the project site. Keep ample supplies of spill cleanup materials onsite. Vehicle and Equipment Fueling NS-9 January 2011 California Stormwater BMP Handbook 3 of 3 Construction www.casqa.org Immediately clean up spills and properly dispose of contaminated soil and cleanup materials. References Blueprint for a Clean Bay: Best Management Practices to Prevent Stormwater Pollution from Construction Related Activities; Santa Clara Valley Nonpoint Source Pollution Control Program, 1995. Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance, Working Group Working Paper; USEPA, April 1992. Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Stormwater Management for Construction Activities, Developing Pollution Prevention Plans and Best Management Practices, EPA 832-R-92005; USEPA, April 1992. Vehicle & Equipment Maintenance NS-10 January 2011 California Stormwater BMP Handbook 1 of 4 Construction www.casqa.org Description and Purpose Prevent or reduce the contamination of stormwater resulting from vehicle and equipment maintenance by running a “dry and clean site”.The best option would be to perform maintenance activities at an offsite facility. If this option is not available then work should be performed in designated areas only,while providing cover for materials stored outside, checking for leaks and spills,and containing and cleaning up spills immediately. Employees and subcontractors must be trained in proper procedures. Suitable Applications These procedures are suitable on all construction projects where an onsite yard area is necessary for storage and maintenance of heavy equipment and vehicles. Limitations Onsite vehicle and equipment maintenance should only be used where it is impractical to send vehicles and equipment offsite for maintenance and repair.Sending vehicles/equipment offsite should be done in conjunction with TC-1, Stabilized Construction Entrance/Exit. Outdoor vehicle or equipment maintenance is a potentially significant source of stormwater pollution. Activities that can contaminate stormwater include engine repair and service, changing or replacement of fluids, and outdoor equipment storage and parking (engine fluid leaks). For further information on vehicle or equipment servicing, see NS-8, Categories EC Erosion Control SE Sediment Control TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control WM Waste Management and Materials Pollution Control Legend: Primary Objective Secondary Objective Targeted Constituents Sediment Nutrients Trash Metals Bacteria Oil and Grease Organics Potential Alternatives None If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Vehicle & Equipment Maintenance NS-10 January 2011 California Stormwater BMP Handbook 2 of 4 Construction www.casqa.org Vehicle and Equipment Cleaning, and NS-9, Vehicle and Equipment Fueling. Implementation Use offsite repair shops as much as possible. These businesses are better equipped to handle vehicle fluids and spills properly. Performing this work offsite can also be economical by eliminating the need for a separate maintenance area. If maintenance must occur onsite, use designated areas, located away from drainage courses. Dedicated maintenance areas should be protected from stormwater runon and runoff, and should be located at least 50 ft from downstream drainage facilities and watercourses. Drip pans or absorbent pads should be used during vehicle and equipment maintenance work that involves fluids, unless the maintenance work is performed over an impermeable surface in a dedicated maintenance area. Place a stockpile of spill cleanup materials where it will be readily accessible. All fueling trucks and fueling areas are required to have spill kits and/or use other spill protection devices. Use adsorbent materials on small spills. Remove the absorbent materials promptly and dispose of properly. Inspect onsite vehicles and equipment daily at startup for leaks,and repair immediately. Keep vehicles and equipment clean; do not allow excessive build-up of oil and grease. Segregate and recycle wastes, such as greases, used oil or oil filters, antifreeze, cleaning solutions, automotive batteries, hydraulic and transmission fluids. Provide secondary containment and covers for these materials if stored onsite. Train employees and subcontractors in proper maintenance and spill cleanup procedures. Drip pans or plastic sheeting should be placed under all vehicles and equipment placed on docks, barges, or other structures over water bodies when the vehicle or equipment is planned to be idle for more than 1 hour. For long-term projects, consider using portable tents or covers over maintenance areas if maintenance cannot be performed offsite. Consider use of new, alternative greases and lubricants, such as adhesive greases, for chassis lubrication and fifth-wheel lubrication. Properly dispose of used oils, fluids, lubricants, and spill cleanup materials. Do not place used oil in a dumpster or pour into a storm drain or watercourse. Properly dispose of or recycle used batteries. Do not bury used tires. Vehicle & Equipment Maintenance NS-10 January 2011 California Stormwater BMP Handbook 3 of 4 Construction www.casqa.org Repair leaks of fluids and oil immediately. Listed below is further information if you must perform vehicle or equipment maintenance onsite. Safer Alternative Products Consider products that are less toxic or hazardous than regular products. These products are often sold under an “environmentally friendly” label. Consider use of grease substitutes for lubrication of truck fifth-wheels. Follow manufacturers label for details on specific uses. Consider use of plastic friction plates on truck fifth-wheels in lieu of grease. Follow manufacturers label for details on specific uses. Waste Reduction Parts are often cleaned using solvents such as trichloroethylene, trichloroethane, or methylene chloride. Many of these cleaners are listed in California Toxic Rule as priority pollutants. These materials are harmful and must not contaminate stormwater. They must be disposed of as a hazardous waste. Reducing the number of solvents makes recycling easier and reduces hazardous waste management costs. Often, one solvent can perform a job as well as two different solvents. Also, if possible, eliminate or reduce the amount of hazardous materials and waste by substituting non-hazardous or less hazardous materials. For example, replace chlorinated organic solvents with non-chlorinated solvents. Non-chlorinated solvents like kerosene or mineral spirits are less toxic and less expensive to dispose of properly. Check the list of active ingredients to see whether it contains chlorinated solvents. The “chlor” term indicates that the solvent is chlorinated. Also, try substituting a wire brush for solvents to clean parts. Recycling and Disposal Separating wastes allows for easier recycling and may reduce disposal costs. Keep hazardous wastes separate, do not mix used oil solvents, and keep chlorinated solvents (like,- trichloroethane) separate from non-chlorinated solvents (like kerosene and mineral spirits). Promptly transfer used fluids to the proper waste or recycling drums. Don’t leave full drip pans or other open containers lying around. Provide cover and secondary containment until these materials can be removed from the site. Oil filters can be recycled. Ask your oil supplier or recycler about recycling oil filters. Do not dispose of extra paints and coatings by dumping liquid onto the ground or throwing it into dumpsters. Allow coatings to dry or harden before disposal into covered dumpsters. Store cracked batteries in a non-leaking secondary container. Do this with all cracked batteries, even if you think all the acid has drained out. If you drop a battery, treat it as if it is cracked. Put it into the containment area until you are sure it is not leaking. Costs All of the above are low cost measures. Higher costs are incurred to setup and maintain onsite maintenance areas. Vehicle & Equipment Maintenance NS-10 January 2011 California Stormwater BMP Handbook 4 of 4 Construction www.casqa.org Inspection and Maintenance Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events. Inspect BMPs subject to non-stormwater discharges daily while non-stormwater discharges occur. Keep ample supplies of spill cleanup materials onsite. Maintain waste fluid containers in leak proof condition. Vehicles and equipment should be inspected on each day of use. Leaks should be repaired immediately or the problem vehicle(s) or equipment should be removed from the project site. Inspect equipment for damaged hoses and leaky gaskets routinely. Repair or replace as needed. References Blueprint for a Clean Bay: Best Management Practices to Prevent Stormwater Pollution from Construction Related Activities; Santa Clara Valley Nonpoint Source Pollution Control Program, 1995. Coastal Nonpoint Pollution Control Program; Program Development and Approval Guidance, Working Group, Working Paper; USEPA, April 1992. Stormwater Quality Handbooks -Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000. Alexan Arcadia 61 December 2023 Appendix I: BMP Inspection Form Alexan Arcadia 62 December 2023 BMP INSPECTION REPORT Date and Time of Inspection: Date Report Written: Inspection Type: (Circle one) Weekly Complete Parts I,II,III and VII Pre-Storm Complete Parts I,II,III,IV and VII During Rain Event Complete Parts I, II, III, V, and VII Post-Storm Complete Parts I,II,III,VI and VII Part I. General Information Site Information Construction Site Name: Construction stage and completed activities: Approximate area of site that is exposed: Photos Taken: (Circle one) Yes No Photo Reference IDs: Weather Estimate storm beginning: (date and time) Estimate storm duration: (hours) Estimate time since last storm: (days or hours) Rain gauge reading and location: (in) Is a “Qualifying Event” predicted or did one occur (i.e., 0.5” rain with 48-hrs or greater between events)? (Y/N) If yes, summarize forecast: Exemption Documentation (explanation required if inspection could not be conducted). Visual inspections are not required outside of business hours or during dangerous weather conditions such as flooding or electrical storms. Inspector Information Inspector Name: Inspector Title: Signature: Date: Part II. BMP Observations. Describe deficiencies in Part III. Alexan Arcadia 63 December 2023 Minimum BMPs for Risk Level _____ Sites Failures or other short comings (yes, no, N/A) Action Required (yes/no) Action Implemented (Date) Good Housekeeping for Construction Materials Inventory of products (excluding materials designed to be outdoors) Stockpiled construction materials not actively in use are covered and bermed All chemicals are stored in watertight containers with appropriate secondary containment, or in a completely enclosed storage shed Construction materials are minimally exposed to precipitation BMPs preventing the off-site tracking of materials are implemented and properly effective Good Housekeeping for Waste Management Wash/rinse water and materials are prevented from being disposed into the storm drain system Portable toilets are contained to prevent discharges of waste Sanitation facilities are clean and with no apparent for leaks and spills Equipment is in place to cover waste disposal containers at the end of business day and during rain events Discharges from waste disposal containers are prevented from discharging to the storm drain system / receiving water Stockpiled waste material is securely protected from wind and rain if not actively in use Procedures are in place for addressing hazardous and non- hazardous spills Appropriate spill response personnel are assigned and trained Equipment and materials for cleanup of spills is available onsite Washout areas (e.g., concrete) are contained appropriately to prevent discharge or infiltration into the underlying soil Good Housekeeping for Vehicle Storage and Maintenance Measures are in place to prevent oil, grease, or fuel from leaking into the ground, storm drains, or surface waters All equipment or vehicles are fueled, maintained, and stored in a designated area with appropriate BMPs Vehicle and equipment leaks are cleaned immediately and disposed of properly Part II. BMP Observations Continued. Describe deficiencies in Part III. Alexan Arcadia 64 December 2023 Minimum BMPs for Risk Level _____ Sites Adequately designed, implemented and effective (yes, no, N/A) Action Required (yes/no) Action Implemented (Date) Good Housekeeping for Landscape Materials Stockpiled landscape materials such as mulches and topsoil are contained and covered when not actively in use Erodible landscape material has not been applied 2 days before a forecasted rain event or during an event Erodible landscape materials are applied at quantities and rates in accordance with manufacturer recommendations Bagged erodible landscape materials are stored on pallets and covered Good Housekeeping for Air Deposition of Site Materials Good housekeeping measures are implemented onsite to control the air deposition of site materials and from site operations Non-Stormwater Management Non-Stormwater discharges are properly controlled Vehicles are washed in a manner to prevent non-stormwater discharges to surface waters or drainage systems Streets are cleaned in a manner to prevent unauthorized non- stormwater discharges to surface waters or drainage systems. Erosion Controls Wind erosion controls are effectively implemented Effective soil cover is provided for disturbed areas inactive (i.e., not scheduled to be disturbed for 14 days) as well as finished slopes, open space, utility backfill, and completed lots The use of plastic materials is limited in cases when a more sustainable, environmentally friendly alternative exists. Sediment Controls Perimeter controls are established and effective at controlling erosion and sediment discharges from the site Entrances and exits are stabilized to control erosion and sediment discharges from the site Sediment basins are properly maintained Linear sediment control along toe of slope, face of slope an at grade breaks (Risk Level 2 & 3 Only) Limit construction activity to and from site to entrances and exits that employ effective controls to prevent offsite tracking (Risk Level 2 & 3 Only) Ensure all storm, drain inlets and perimeter controls, runoff control BMPs and pollutants controls at entrances and exits are maintained and protected from activities the reduce their effectiveness (Risk Level 2 & 3 Only) Alexan Arcadia 65 December 2023 Inspect all immediate access roads daily (Risk Level 2 & 3 Only) Run-On and Run-Off Controls Run-on to the site is effectively managed and directed away from all disturbed areas. Other Are the project SWPPP and BMP plan up to date, available onsite and being properly implemented? Part III. Descriptions of BMP Deficiencies Deficiency Repairs Implemented: Note - Repairs must begin within 72 hours of identification and, complete repairs as soon as possible. Start Date Action 1. 2. 3. 4. Part IV. Additional Pre-Storm Observations. Note the presence or absence of floating and suspended materials, sheen, discoloration, turbidity, odors, and source(s) of pollutants(s). Yes, No, N/A Do stormwater storage and containment areas have adequate freeboard? If no, complete Part III. Are drainage areas free of spills, leaks, or uncontrolled pollutant sources? If no, complete Part VII and describe below. Notes: Are stormwater storage and containment areas free of leaks? If no, complete Parts III and/or VII and describe below. Notes: Alexan Arcadia 66 December 2023 Part V. Additional During Storm Observations. If BMPs cannot be inspected during inclement weather, list the results of visual inspections at all relevant outfalls, discharge points, and downstream locations. Note odors or visible sheen on the surface of discharges. Complete Part VII (Corrective Actions) as needed. Outfall, Discharge Point, or Other Downstream Location Location Description Location Description Location Description Location Description Location Description Location Description Location Description Location Description Alexan Arcadia 67 December 2023 Part VI. Additional Post-Storm Observations. Visually observe (inspect) stormwater discharges at all discharge locations within two business days (48 hours) after each qualifying rain event, and observe (inspect) the discharge of stored or contained stormwater that is derived from and discharged subsequent to a qualifying rain event producing precipitation of ½ inch or more at the time of discharge. Complete Part VII (Corrective Actions) as needed. Discharge Location, Storage or Containment Area Visual Observation Part VII. Additional Corrective Actions Required. Identify additional corrective actions not included with BMP Deficiencies (Part III) above. Note if SWPPP change is required. Required Actions Implementation Date Alexan Arcadia 68 December 2023 Appendix J: Project Specific Rain Event Action Plan Template REAP is not required for Risk Level 1 project. Alexan Arcadia 69 December 2023 Appendix K: Training Reporting Form Alexan Arcadia 70 December 2023 Trained Contractor Personnel Log Stormwater Management Training Log and Documentation Project Name: Alexan Arcadia WDID #: _______________ Stormwater Management Topic: (check as appropriate) Erosion Control Sediment Control Wind Erosion Control Tracking Control Non-Stormwater Management Waste Management and Materials Pollution Control Stormwater Sampling Specific Training Objective: Location: Date: _ Instructor: Telephone: Course Length (hours): Attendee Roster (Attach additional forms if necessary) Name Company Phone As needed, add proof of external training (e.g., course completion certificates, credentials for QSP, QSD). Alexan Arcadia 71 December 2023 Appendix L: Responsible Parties 4/26/2018 CA Storm water Multiple Applications and Report Tracking System - Ver 2015.11 Bld: 10.28.2015.8.40 https://smarts.waterboards.ca.gov/smarts/faces/Enrollment/QsdCertification.xhtml 1/1 Help Logout You are logged-in as: LEAH ISIDRO If this account does not belong to you, please log out. Navigate To: CBPELSG - QSD Acknowledgement Your CBPELS QSD registration is complete. Your CBPELS License number is now your QSD Certification number First Name:LEAH Last Name:ISIDRO Certificate No.:C78541 Effective Date:Apr 26, 2018 Return to Main Menu Alexan Arcadia 72 December 2023 Identification of QSP Project Name: Alexan Arcadia WDID #: The following are QSPs associated with this project Name of Personnel(1) Company Date (1) If additional QSPs are required on the job site add additional lines and include information here Alexan Arcadia 73 December 2023 Appendix M: Contractors and Subcontractors Alexan Arcadia 74 December 2023 Appendix N: Calculations Alexan Arcadia 75 December 2023 Appendix O: Weather Reports The discharger must obtain the precipitation forecast information from the National Weather Service Forecast Office (http://forecast.weather.gov ). A printed copy should be retained in this Appendix. Alexan Arcadia 76 December 2023 Appendix P: Monitoring Records Alexan Arcadia 77 December 2023 Appendix Q: Example Storm Event Monitoring Forms Alexan Arcadia 78 December 2023 Rain Gauge Log Sheet Construction Site Name: WDID #: 4 19C392717 Date (mm/dd/yy) Time (24-hr) Initials Rainfall Depth (Inches) Notes: Alexan Arcadia 79 December 2023 Risk Level 1, 2, 3 Visual Inspection Field Log Sheet Date and Time of Inspection: Report Date: Inspection Type: □ Weekly □ Before predicted rain □ During rain event □ Following qualifying rain event □ Contained stormwater release □ Quarterly non- stormwater Site Information Construction Site Name: Construction stage and completed activities: Approximate area of exposed site: Weather and Observations Date Rain Predicted to Occur: Predicted % chance of rain: Estimate storm beginning: (date and time) Estimate storm duration:_________ (hours) Estimate time since last storm: ________ (days or hours) Rain gauge reading: _______ (inches) Observations: If yes identify location Odors Yes □ No □ Floating material Yes □ No □ Suspended Material Yes □ No □ Sheen Yes □ No □ Discolorations Yes □ No □ Turbidity Yes □ No □ Site Inspections Outfalls or BMPs Evaluated Deficiencies Noted (add additional sheets or attached detailed BMP Inspection Checklists) Photos Taken: Yes □ No □ Photo Reference IDs: Corrective Actions Identified (note if SWPPP/REAP change is needed) Inspector Information Inspector Name: Inspector Title: Signature: Date: Risk Level 2 Alexan Arcadia 80 December 2023 Effluent Sampling Field Log Sheets Construction Site Name: Date: Time Start: Sampler: Sampling Event Type: □ Stormwater □ Non-stormwater □ Non-visible pollutant Field Meter Calibration pH Meter ID No./Desc.: Calibration Date/Time: Turbidity Meter ID No./Desc.: Calibration Date/Time: Field pH and Turbidity Measurements Discharge Location Description pH Turbidity Time Grab Samples Collected Discharge Location Description Sample Type Time Additional Sampling Notes: Time End: Alexan Arcadia 81 December 2023 Risk Level 3 Effluent Sampling Field Log Sheets Construction Site Name: Date: Time Start: Sampler: Sampling Event Type: □ Stormwater □ Non-stormwater □ Non-visible pollutant Field Meter Calibration pH Meter ID No./Desc.: Calibration Date/Time: Turbidity Meter ID No./Desc.: Calibration Date/Time: Field pH and Turbidity Measurements Discharge Location Description pH Turbidity Time Grab Samples Collected Discharge Location Description Other (specify) Time Additional Sampling Notes: Time End: Alexan Arcadia 82 December 2023 Risk Level 3 Receiving Water Sampling Field Log Sheets Construction Site Name: Date: Time Start: Sampler: Receiving Water Description and Observations Receiving Water Name/ID: Observations: Odors Yes □ No □ Floating material Yes □ No □ Suspended Material Yes □ No □ Sheen Yes □ No □ Discolorations Yes □ No □ Turbidity Yes □ No □ Field Meter Calibration pH Meter ID No./Desc.: Calibration Date/Time: Turbidity Meter ID No./Desc.: Calibration Date/Time: Field pH and Turbidity Measurements and SSC Grab Sample Upstream Location Type Result Time Notes pH Turbidity SSC Collected Yes □ No □ Downstream Location Type Result Time Notes pH Turbidity SSC Collected Yes □ No □ Additional Sampling Notes: Time End: Alexan Arcadia 83 December 2023 NAL Exceedance Evaluation Summary Report Page __ of __ Project Name Project WDID 4 19C392717 Project Location Date of Exceedance Type of Exceedance NAL Daily Average pH Turbidity Other (specify) Measurement or Analytical Method Field meter (Sensitivity: ) Lab method (specify) (Reporting Limit: ) (MDL: ) Calculated Daily Average pH pH units Turbidity NTU Rain Gauge Measurement inches Compliance Storm Event inches (5-year, 24-hour event) Visual Observations on Day of Exceedance Alexan Arcadia 84 December 2023 NAL Exceedance Evaluation Summary Report Page __ of __ Description of BMPs in Place at Time of Event Initial Assessment of Cause Corrective Actions Taken (deployed after exceedance) Additional Corrective Actions Proposed Report Completed By (Print Name, Title) Signature Alexan Arcadia 85 December 2023 CHAIN-OF-CUSTODY DATE: Lab ID: DESTINATION LAB: REQUESTED ANALYSIS Notes: ATTN: ADDRESS: Office Phone: Cell Phone: SAMPLED BY: Contact: Project Name Client Sample ID Sample Sample Sample Container Date Time Matrix # Type Pres. SENDER COMMENTS: RELINQUISHED BY Signature: Print: Company: Date: TIME: LABORATORY COMMENTS: RECEIVED BY Signature: Print: Company: Date: TIME: Alexan Arcadia 86 December 2023 Appendix R: Field Meter Instructions Alexan Arcadia 87 December 2023 Appendix S: Supplemental Information