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HomeMy WebLinkAboutItem 2g: Accept Work by Palm Springs Pump and Drilling for Destruction of Longely Well No. 2 and Camino Real Well No. 1DATE: December 15, 2009 TO: Mayor and City Council STAFF REPORT Public Works Services Department FROM: Pat Malloy, Assistant City Manager /Public Works Services Direct Prepared by: Lubomir Tomaier, Principal Civil Engineer Ken Herman, Associate Civil Engineer SUBJECT: ACCEPT ALL WORK PERFORMED BY PALM SPRINGS PUMP & DRILLING FOR THE DESTRUCTION OF LONGLEY WELL NO. 2 AND CAMINO REAL WELL NO. 1 PROJECT AS COMPLETE AND AUTHORIZE THE FINAL PAYMENT TO BE MADE IN ACCORDANCE WITH CONTRACT DOCUMENTS Recommendation: Approve SUMMARY On September 1, 2009, the City Council awarded a contract to Palm Springs Pump & Drilling in the amount of $28,500 for the Destruction of Longley Well No. 2 and Camino Real Well No.1 Project, plus a 10% contingency for a total project cost of $31,350. The terms and conditions of this project have been complied with and the work has been performed to staff's satisfaction for a total project cost of $35,890.30. This amount reflects the original contract amount of $28,500 plus one Change Order totaling $7,390.30 or 25.9% above the original contract amount. Staff recommends that the City Council accept all work performed by Palm Springs Pump & Drilling as complete and authorize the final payment to be made in accordance with the contract documents. BACKGROUND Longley Well No. 2 was constructed in March of 1949 and production of the well was stopped in 1977 due to nitrate contamination. Camino Real Well No. 1 was constructed in December of 1949. In the later years of its production the well developed sanding problems and collapsed in 1993. Both wells are also in the process of being replaced with the construction of Longley Well No. 3 and Camino Well No. 3. Page 1 of 3 Mayor and City Council December 15, 2009 DISCUSSION Both wells were destroyed in compliance with California Department of Public Health requirements intended to limit contamination of ground water aquifers through out -of- service wells. The destruction process for both wells was witnessed by a representative (inspector) for the Los Angeles County Department of Environmental Health. Destruction of a well involves cleaning out all loose or deleterious material from the well casing, filling the lower section of casing with concrete slurry, perforating the upper section of blank casing, and filling that section with concrete. The weight of the concrete in the casing pushes the concrete slurry out through the louvers and perforations into any voids that may exist outside the casing (see attachment for pre and post well destruction process). It is difficult to project the amount of concrete and concrete slurry necessary to fill a well. The amount of underground voids behind the casing wall is generally unknown and can be difficult and costly to determine. For the purposes of bidding, the volume of the well casing is used as the volume of fill material required to fill the well. Payment is based on the actual volume of material used to fill the well which is determined from material delivery tickets. This volume may vary based on the voids which may be present beyond the well casing. Per Health Department inspector direction and due to the large amount of underground voids, the contractor had to install additional concrete at the Camino Real facility (39 cubic yards) and at the Longley facility (27 cubic yards). These amounts exceeded the amount of concrete reflected in the original bid quantity. The change order reflects the cost for the extra concrete required to fill the two wells. Public works staff negotiated the extra cost with the contractor to pay only for material, but not for extra labor and equipment cost to place the extra material. Project Cost Original Contract Amount Change Order No.1 Additional 66 cubic yards of concrete installed per California Public Health Department requirement to seal underground voids around decommissioned wells $ 28,500.00 $ 7,390.30 Total Contract Cost $ 35,890.30 The terms and conditions of this contract have been complied with and the work has been performed to staff's satisfaction. Therefore, staff recommends that the City Council accept all work performed by Palm Springs Pump & Drilling as complete and authorize the final payment to be made in accordance with the contract documents, subject to retention of $3,589.03. Page 2 of 3 Mayor and City Council December 15, 2009 ENVIRONMENTAL IMPACT: On November 18, 2008 the City Council adopted Mitigated Negative Declaration for the project satisfying all CEQA requirements. FISCAL IMPACT Water Funds in the amount of $3,400,000 are budgeted in the '2008-2009 Capital Improvement Program for the Longley and Camino Well Construction Project. Well destruction is included as a part of this work. RECOMMENDATIONS 1. Accept all work performed by Palm Springs Pump & Drilling for the Destruction of Longley Well No. 2 and Camino Real Well No.1 Project as complete. 2. Authorize final payment to be made in accordance with the contract documents, subject to retention of $3,589.03. PM:LT:KH Approved by: Page 3 of 3 Donald Penman, City Manager GROUND LEVEL GRAVEU SAND WATER BEARING STRATA GRAVEL/ SAND WATER BEARING STRATA PRE - DESTRUCTION 1 WELL PEDESTAL GROUND LEVEL 23 SACKS NEAT CEMENT NEW PERFORATIONS 23 SACKS NEAT CEMENT POST - DESTRUCTION WELL PEDESTAL EW PERFORATIONS 23 SACKS NEAT CEMENT GRAVEU SAND WATER BEARING STRATA GRAVED SAND WATER BEARING STRATA NEW PERFORATIONS