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A S S O C I A T E S I N C ' boring/well construction logs contained in Appendix A Soil borings MW1 through MW3 were advanced and completed as groundwater monitoring wells ' 2.2 Soil Sample Analysis ' Selected soil samples were placed on ice, and transported under chain-of-custody to Argon Laboratories, Inc (DHS Certification No 2359) of Ceres, California for chemical analysis All soil samples were analyzed for TPHg and BTEX utilizing EPA 8015 and 8020 methodologies, and oxygenate fuel additives utilizing EPA 8260 methodology The analytical results for soil samples are summarized in Table 1 Laboratory data sheets and chain-of-custody documentation are included in Appendix B t2.3 Groundwater Monitoring Well Construction tSoil borings MW1 through MW3 were subsequently completed as groundwater monitoring wells to assess groundwater beneath the site ' The wells were constructed with 2-inch PVC casing to depths of approximately 91 feet bgs The screened intervals of the wells were positioned from approximately 5 feet above to 15 feet below the encountered water table to allow for seasonal water level fluctuations The screen slot size utilized is 0 020-inch The wells were completed with traffic rated utility boxes and the well casings were secured with keyed locks Well construction details are depicted on the well logs contained in Appendix A The three new wells were surveyed on June 25, 1999 to an arbitrary elevation Survey data is contained in Table 3 2,.4 Monitoring Well Development and Sampling ' On June 25, 1999, depth to water measurements in all on-site monitoring wells were collected to evaluate the direction and magnitude of the groundwater gradient beneath the site The new wells were subsequently developed using surge and bail techniques until the produced water is ' relatively sediment free Prior to the collection of groundwater samples, a minimum of three well volumes (casing and sand pack) were purged Temperature, pH, and electric conductivity were measured and allowed to stabilize Water samples were collected using disposable bailers, one dedicated to each well Groundwater elevation data are presented in Table 3 ' Additionally, as requested in PHS/EHD's October 9, 1998 correspondence, ATC sampled the on- site domestic well The well was sampled from an existing sampling port located near the wellhead Approximately 150 gallons of water was purged from the domestic well prior to sampling Field development/purge logs are presented in Appendix C ' w 1148851reports\Supp1 Invest doe 3