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Former Discovery Chevrolet December 7, 1994 Soil Boring and Sampling . Three onsite soil borings were drilled and groundwater monitoring wells (MW-1 MW-2, and .MW-3) were installed on September 10, 1994. The borings were situated to evaluate the soil and groundwater in and around the former UST locations. The borings were drilled and the monitoring wells installed using a truck-mounted hollow-stem auger rig by Geo-Environmental Drilling of Yuba City, California (license #C57-676923). A GSI geologist observed the drilling of the borings, described the encountered soil, and prepared a log of each boring. Logs of Borings .are presented in Appendix B. Well borings MW-1 , MW-2, and MW-3 were drilled to 20 feet bgs with 8-inch diameter hollow-stem augers. Soil samples were collected with a split spoon sampler at approximately 5 foot intervals in each boring. Soil samples were evaluated with a photoionization detector (PID) and selected soils samples were transported to the laboratory for requested analyses. Procedures used for collecting and handling samples are presented in Appendix A. Groundwater monitoring wells were constructed in the borings, as discussed below. Mr. Steve Sasson of the SJCEHD was present to observe the sampling of the borings and placement of well. seals. '.Monitoring Well Installation Monitoring wells were constructed of two-inch diameter Schedule 40 polyvinyl chloride (PVC) casing and 0.02-inch machine-slotted screen. The annular space around the screen was packed with Lonestar #3 graded sand. A one- to two-foot thick bentonite seal was placed above the sandpack, and the remaining annular space sealed with neat cement. The top of each well is protected by.a water- resistant vault box set in concrete, a locking waterproof well cap, and a lock. Well construction details are presented with the Logs of Boring in Appendix B. Well Development The monitoring wells were developed by G-R on September 14, 1994. G-R well development procedures are presented in Appendix A. Each well was alternately surged with a bailer, then purged to remove accumulated sediments and improve hydraulic communication between the well and the surrounding aquifer. Approximately 50 gallons of groundwater were removed from each well. Development water was stored in properly labeled 55 gallon Department of Transportation (DOT) approved drums pending proper disposal. Well development Report Na.8146701.1 3 GeoStrategies Inc.