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1 09 April 2002 <br /> . AGE-NC Project No 98-0497 <br /> 1 Page 3 of 6 <br /> i Control District and Water Control District) dating back to 1971 suggests that ground water depth <br /> near the site has fluctuated between 60 and 100 feet bsg <br /> Based on the ground water elevation data collected from the three on-site ground water monitoring <br /> wells over the last four quarters, groundwater flow direction at the site is generally toward the east <br /> to east northeast <br /> 1 <br /> 3.0 PROCEDURES <br /> 1 Two ground water monitoring wells (MW-4 and MW-5)were Installed and developed in February <br /> 2002, the two wells were surveyed in March 2002 Field work was performed in accordance with <br /> CVRWQCB guidelines and in accordance with the EHD-approved Monitoring Well Installation <br /> Work Plan Addendum, dated 10 September 2001 <br /> 3 1 DRILLING AND SAMPLING <br /> �. On 14 and 15 February 2002,one soil boring(MW-4)was advanced at the site and two soil borings <br /> (B-1 and MW-5)were advanced at 2900 Loomis Road,Stockton,California(neighboring property) <br /> 1 The soil borings were advanced using a CME-75 drill ng,equipped with 8 25-inch diameter hollow- <br /> stem augers The drill ng and three-man crew were supplied by Mitchell Drilling Environmental <br /> Auger returns generated by drilling were containerized and stored on-site in Department of <br /> ' Transportation (DOT)-approved 55-gallon drums, pending laboratory analysis <br /> Soil samples were collected ahead of the drill bit using a California modified split-spoon sampler <br /> loaded with three pre-cleaned 2-inch by 6-inch brass sleeves The samples were collected from soil <br /> bonngs B-1,MW-4 and MW-5 at five-foot intervals,beginning at 15 feet,20 feet and 30 feet below <br /> surface grade (bsg), respectively, using a 140-pound hammer to advance the sampler The number <br /> of blows required to advance the sampler over each 6-Inch increment of the 18-inch sampling <br /> interval was recorded on the boring logs The sampling equipment was washed in an Alconox <br /> solution and rinsed with water prior to each sampling run to minimize cross-contamination For each <br /> sample, both ends of the leading or other selected sleeve were covered with Teflon sheets, capped <br /> and sealed with tape The samples were labeled,stored on ice and transported under chain-of-custody <br /> to McCampbell Analytical Laboratories (MAI), a State of California Department of Health <br /> I - Services-certified analytical laboratory Selected soil samples were analyzed for <br /> • TPH-g and TPH-d in accordance with EPA Method 8015M, <br /> ' 0 BTEX and MTBE in accordance with EPA Method 8020, and <br /> ' Advanced GeoEnvlronmental,Inc <br />