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BACKGROUND West Las Positas Boulevard between Tassajara Creek (east of Hacienda Drive) and Fiesta Drive (west of Stoneridge Drive) has been settling over time. In the past, the City has provided maintenance repairs in an effort to remediate the uneven roadways and sidewalks that are experiencing pavement distress and/or settlement. In November 2011, the curb lane in the eastbound direction had settled to a point that it created a safety concern and required the lane to be closed to vehicular traffic. In 2010, a geotechnical investigation was performed by Kleinfelder to determine the possible causes of the on-going settlement. Numerous potential causes of the settlement were presented. However, no definitive cause of the settlement was identified and a second opinion by a different geotechnical consultant was deemed necessary. In 2012, ENGEO Incorporated, a geotechnical consultant, was asked for a second opinion and was authorized by the City to provide engineering and construction recommendations for the repair. ENGEO's opinion is that this section of roadway was constructed over a former "marsh and lagoon" area. The "marsh and lagoon" deposits consist of soft, compressible soils with high moisture content that are leading to the damage as the deep soil layers swell and compress. Roadway construction has applied additional loads over the deep soft, soils, causing localized soil swelling and settlement. It is recommended by ENGEO that the distress area should be repaired by replacing the existing soil under the pavement surface with light-weight engineering fill material (cellular concrete). Replacing the existing soils with light-weight material should eliminate or reduce the severity of future settlement in the area currently showing distress. The project will restore the roadway section to the design grade. Approximately 500 cubic yards of existing soil under the severely distressed area will be replaced by light- weight cellular concrete material and approximately 1,200 square feet of less severely distressed area will be repaired by conventional base repair construction method. This project will also include: replacing existing concrete curb and gutter (340 feet), sidewalk (2,200 square feet), non-compliant ADA curb ramps, as well as resurfacing existing roadway surface with asphalt concrete, installing pavement markers, and striping. DISCUSSION Bids Sealed bids for this slurry sealing project were opened on March 26, 2013. There was only one bid received from Fanfa, Inc. in the bid amount of $220,000, which was $12,000 less than the Engineer's estimate of $232,000. Although only one bid was received, the correct public works bidding procedure was followed. Since the bid amount was similar to the engineer's estimate, staff is confident the bid is acceptable. Past work performed by Fanfa, Inc. was verified to be satisfactory. Therefore, staff recommends award of the construction contract to Fanfa, Inc. Budget The project was authorized under the FY 2011-12 Capital Improvement Program (CIP) budget for design and construction with an approved budget of$200,000. Additionally, Page 2 of 3