HomeMy WebLinkAboutItem 11h - Accept Live Oak Well TCE Treatment Construction Project
DATE: August 4, 2020
TO: Honorable Mayor and City Council
FROM: Tom Tait, Public Works Services Director
By: Eddie Chan, P.E., Principal Civil Engineer
SUBJECT: ACCEPT ALL WORK PERFORMED BY PACIFIC HYDROTECH
CORPORATION FOR THE LIVE OAK WELL TCE TREATMENT
CONSTRUCTION PROJECT AS COMPLETE
Recommendation: Approve
SUMMARY
On April 2, 2019, the City Council approved a contract with Pacific Hydrotech
Corporation in the amount of $836,800 for the Live Oak Well TCE Treatment
Construction Project. The terms and conditions of this project have been complied with
and the work has been performed to the satisfaction of the Project Manager for a total
project cost of $887,602.72. This amount reflects the original contract amount of
$836,800 plus quantity changes totaling $50,802.72, or 6.07% more than the original
contract amount.
It is recommended that the City Council accept all work performed by Pacific Hydrotech
Corporation for the Live Oak Well TCE Treatment Construction Project as complete;
and authorize the final payment to be made in accordance with the contract documents,
subject to the retention of $44,380.14.
BACKGROUND
The Public Works Services Department (“PWSD”) is responsible for the daily operation
of City wells and the water that is distributed to the community. Water quality samples
are taken regularly to ensure that the City’s water supply meets state and federal
drinking water standards. Water quality samples taken at Live Oak Well indicated that
levels of Trichloroethylene (“TCE”), a volatile organic compound were increasing. TCE
is a federal and state regulated contaminant with a Maximum Contaminant Level
(“MCL”) of 5 parts per billion. In October 2018, TCE concentrations at Live Oak Well
exceeded the allowable MCL. Consequently, the Live Oak Well was taken out of
service. The Fiscal Year 2018-19 Capital Improvement Program allocated funding for
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August 4, 2020
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the construction of a water treatment system to treat TCE at the Live Oak Well. This
project was separated into two phases to help reduce project costs and cut down on the
construction time period.
On June 19, 2018, the City Council approved a Professional Services Agreement with
ES Engineering Services, LLC for engineering services to design a treatment system at
the Live Oak Well. ES Engineering Services, LLC determined that a Granular Activated
Carbon (“GAC”) adsorption system would be the best method to remove TCE from the
City’s water supply. To keep costs to a minimum and to deal with the anticipated long
lead-time in getting a GAC adsorption system, the PWSD purchased eight GAC
treatment vessels separately and supplied them to Pacific Hydrotech Corporation for
installation. Each GAC treatment vessel is 20 feet high and weighs approximately 52
tons when full of water (shown on Exhibit “A”).
DISCUSSION
On April 2, 2019, the City Council approved a contract with Pacific Hydrotech
Corporation for the Live Oak Well TCE Treatment Construction Project. The work
performed included the demolition of an existing block wall, construction of a concrete
foundation pad to support the GAC vessels, construction and installation of
underground and aboveground piping, fittings, and valves, and installation of the eight
treatment vessels.
During the course of work, it was determined by the structural engineer that due to
changes in the building code, it was necessary to install additional anchor bolts and
larger steel plates at each leg support of the GAC vessels. Four leg supports for each
vessel were installed for a total of 32 leg supports. This resulted in a change order.
Below is a description of the contract change order.
Description Amount
1. Install additional anchor bolts and larger steel plates at each leg
support of the GAC vessels per Building Code requirement $50,802.72
Total: $50,802.72
The terms and conditions of this contract have been complied with and the work has
been performed to the satisfaction of the Project Manager. Pacific Hydrotech
Corporation completed the work as defined in the project plans and specifications in an
efficient and timely manner.
FISCAL IMPACT
Funds in the amount of $2,000,000 were budgeted in the Fiscal Year 2018-19 Capital
Improvement Program for this project. In an effort to keep costs to a minimum and deal
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August 4, 2020
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with the anticipated long lead-time, a portion of the budgeted funds were used to
purchase the eight GAC treatment vessels, leaving $928,720 for the construction phase
of the project. The total cost for construction of the Live Oak Well TCE Treatment is
$887,602.72. The amount reflects the original contract amount of $836,800 plus
quantity changes totaling $50,802.72, or 6.07% more than the original contract amount.
RECOMMENDATION
It is recommended that the City Council accept all work performed by Pacific Hydrotech
Corporation for the Live Oak Well TCE Treatment Construction Project as complete;
and authorize the final payment to be made in accordance with the contract documents,
subject to the retention of $44,380.14.
Attachment: Exhibit “A” – Photographs of GAC Treatment Vessels
EXHIBIT “A”
Live Oak Well GAC Treatment Vessels