Laserfiche WebLink
Supplemental Investigation Work Plan <br /> BP Oil Site No. 11193 + <br /> C A M B R I A Stockton, California <br /> February 25, 2000 <br /> PROPOSED SCOPE OF WORK <br /> Our proposed scope of work includes replacement of wells MW-1 and MW-2 with 4-inch diameter <br /> wells, installation of three monitoring wells for lateral and vertical definition, evaluation of the <br /> nearby Caltrans well, estimation of hydrocarbon and MTBE mass remaining, and continued <br /> quarterly groundwater monitoring. We understand that TOSCO will provide a proposal for <br /> groundwater extraction under separate cover. j <br /> Monitoring Well Replacement and Installation <br /> Utility Location: The proposed drilling locations will be marked and Underground Service Alert <br /> will be notified of our site activities to identify utilities in the site vicinity. In addition, available as- <br /> built diagrams will be reviewed to evaluate subsurface obstructions in the vicinity of the proposed ! <br /> drilling locations. <br /> ' Access Agreement: An access agreement will be acquired from the car wash property located south <br /> of the site where a monitoring well is proposed. SJCEHD assistance with determining the owner <br /> i 1 of the car wash property will expedite acquisition of the access agreement. <br /> {I. Site Health and Safety Plan: A comprehensive site safety plan will be prepared for the benefit of <br /> site workers. The plan will be kept on site during field activities and signed by each site worker. j <br /> Permits: Well installation and abandonment permits will be acquired from the SJCEHD. <br /> Monitoring Well Replacement: During tank replacement activities, well MW-1 was destroyed and <br /> well MW-2 was apparently damaged (see Figure 2). Well MW-2 will be destroyed by overdrilhng <br /> with 10-inch diameter hollow-stem augers and the borehole will be converted to a 4-inch diameter <br /> well (see Appendices C and D). A second 4-inch diameter well will be installed adjacent to well <br /> { 2MW=1. These wells will screen from ]0 to 30 feet bgs: <br /> Monitoring Well Installation: Two 2-inch diameter monitoring wells, one located near boring CB-G <br /> and the other located south of boring CB-2 at the adjacent car wash property, will be used to monitor <br /> the lateral extent of hydrocarbons and MTBE in groundwater (see Figure 2). The wells will be <br /> drilled using 8-inch diameter hollow-stem augers and screen from 10 to 30 feet bgs. <br /> I <br /> 6 <br />