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tv C o A S S O C f A T E 5 1 14 C The cored soil samples were collected at five-foot intervals or significant changes in lzthology using a 2-inch diameter split-spoon sampler containing three brass tubes The cored samples and drill cuttings were characterized for soil type, moisture content, and visual evidence of petroleum hydrocarbons A flame ionization detection meter (FID) was used as a field-screening device for the detection of petroleum hydrocarbon vapors in drill cuttings and cored samples Drill cuttings were temporarily stored on site in 55-gallon DOT approved steel drums ' 2_3 Soil Sample Analysis ' Selected soil samples were placed on ice, and transported under chain-of-custody to State- certified Argon Laboratories Inc (ELAP Cert No 2359) in Ceres, California for analysis Selected soil samples were analyzed for total petroleum hydrocarbons as gasoline (TPHg) ' utilizing EPA Method 8015, BTEX utilizing EPA Method 8020, and oxygenate fuel additives including methyl tertiary butyl ether (MTBE), tertiary amyl ether (TAME), ethyl tertiary butyl ether (ETBE), di-isopropyl ether (DIPE), tertiary butyl alcohol (TBA) utilizing EPA Method ' 8260 The analytical results for soil samples are summarized in Table I Laboratory data sheets and chain-of-custody documentation are included in Appendix C 224 Groundwater Monitoring Well Construction Soil borings MW4, MWS, MW6, MW7, and MW8 were subsequently completed as groundwater monitoring wells to assess impacted groundwater beneath the site, and to provide measurement points for the determination of groundwater flow direction and hydraulic gradient The wells were surveyed on December 14, 2000 and tied into the elevations of the existing groundwater wells Survey results are contained in Table 3 ' Each well was constructed with 2-inch PVC casing The screened interval of wells MW4, MW5, MW6, and MW7 was positioned from approximately 5 feet above to 15 feet below the encountered water table (60 to 80 feet bgs) to allow for seasonal water level fluctuations The screened interval of well MW8 was placed from 85 to 100 feet bgs The screen slot size is 0 020- inch Well construction details are depicted on the well logs contained in Appendix B ' 25 Monitoring Well Development Groundwater monitoring wells MW4, MW5, MW6, MW7, and MW8 were developed on ' December 14 and 15, 2000 Each well was purged until the extracted water was relatively sediment free Development logs are included in Appendix D Purgewater was temporarily stored on site in 55-gallon drums Fluid levels were taken on December 14, 2000, utilizing an ' electronic water probe capable of measuring with an accuracy of 11100 of a foot Groundwater elevation data are presented in Table 3 1 w 1163931reportslsumii doc 3