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BACKGROUND Sanitary sewer pump station S-6 was constructed in the 1960's. It is located at the northeast corner of the intersection of the Arroyo Mocho and Alamo Canal in northwest Pleasanton. It is adjacent to the West Las Positas Boulevard over-crossing of Interstate 1-680. This pump station consisted of a "metal can" dry well configuration pumping from an adjacent concrete wet well into a force main that runs northerly to the Dublin San Ramon Services District (DSRSD) treatment plant. The pumping equipment, electrical systems, and pump station building were all in poor condition. The pumps operated with capacity problems under both dry weather and wet weather flow conditions. On March 1, 2011, City Council approved the construction contract to Anderson Pacific Engineering Construction, Inc. in the amount of $2,083,000. A new 7.6 MGD pump station was constructed and then the existing 3.9 MGD pump station was removed. The project included the purchase of the pump station parcel from Caltrans for $160,200. In addition, the contract with the design engineer, Carollo Engineers, was amended to provide construction support services. The project has since been completed and is ready for acceptance. DISCUSSION This project is part of the City's preventative maintenance program to repair and replace the aging infrastructure, reducing long-term operation and maintenance costs. The project increased the capacity of the pump station and is designed to accommodate the remaining future growth of the pump station service area. There were twenty construction change orders issued for the project resulting in a net increase of $91,351, approximately 4% of the original contract and within the approved project contingency. Major change orders included: the undergrounding of the phone line that had to be removed from the poles because of utility conflicts, installation of a new water service for additional capacity, epoxy injection to repair leaks in the existing wet well, additional modifications to the motor control center, material escalation costs, change in the coating system for piping, and modifications to the slide gates to accommodate existing conditions in the old wet well. Carrollo Engineers, the designer, was back-charged for a change order associated with an error on the coordinates shown on the drawings. Total project expenditures are $3,101,339 (see Attachment 1 for a Funding and Expenditure Summary). A project balance of $1,095,870 is remaining and staff recommends the balance be returned to the Sewer and Replacement Fund balance. All of the contract work has been completed to the City's satisfaction. This project is now complete and ready for City Council acceptance. Page 2 of 3