Laserfiche WebLink
� v � <br /> SITE BACKGROUND <br /> Site Description <br /> The Site is located in the Central Valley, at the foot of the eastern edge of the Diablo <br /> Range. The Site is located within a farmed field and topographically slopes toward the <br /> northeast. Soils underlying the site consist of clays, silts, sands, and gravels, deposited <br /> as alluvial fans. The average depth to groundwater is approximately 35 feet below <br /> ground surface(ft bgs). <br /> A surface water feature noted on maps of the area and titled "Upper Main Canal', <br /> belongs to the West Side Irrigation District. It is not currently known if the canal is <br /> lined. This canal is approximately one quarter mile northeast of the former pipelines. A <br /> larger canal, the Delta-Mendota Canal, is located to the southwest of the site, almost a <br /> mile from the former pipelines. <br /> Site History and Current and Future Land Use <br /> The Central Valley Crude Pipelines carried crude oil from the Central Valley to the Bay <br /> Area. The pipelines are located in the western portion of the Central Valley and the <br /> subject Site is located within the city limits of Tracy. The Site consists of an <br /> approximately 2 mile section of the former Shell Oil Company (Shell) pipelines located <br /> extending southeast of Interstate 205 across Hansen Road and north of Schulte Road. At <br /> this Site, Shell operated two pipelines, running in a northwest-southeastern direction <br /> through a farmed property. The area is currently underdeveloped and used seasonally <br /> for farming. There are conceptual plans to re-develop the property for commercial <br /> building use. <br /> During 2001, Shell agreed to remove the pipeline in advance of the scheduled <br /> development. The pipelines were buried at a depth of approximately 4 ft bgs. During <br /> pipeline removal, six areas surrounding the pipelines were observed to be impacted by <br /> petroleum hydrocarbons. These areas are referred to as Trenches 1 through 6 or Areas 1 <br /> through 6. Shell performed over-excavation activities at Trenches 1 and 2, and removed <br /> impacted soils to depths between 15 and 20 ft bgs. Trenches 3 through 6 were <br /> approximately 4 feet deep, corresponding with the depth of the pipeline burial and no <br /> overexcavation was performed. <br /> 060223(33) A-1 <br /> CONESTOGA-ROVERS&ASSOCIATES <br />