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� A v Z A S S O C I A T E S I N C for seasonal water level fluctuations The screen slot size is 0 020-inch Well construction details are depicted on the well logs contained in Appendix A ' 22.44 Monitoring Well Development Groundwater monitoring wells MW 1, MW2, and MW3 were developed on November 16, 1998 Each well was purged until the extracted water was relatively sediment free Development/purge logs are included in Appendix C Purgewater was temporarily stored on site in 55-gallon drums ' After fluid levels had been allowed to stabilize, groundwater levels were obtained from wells MW 1, MW2, and MW3 Fluid levels were taken on November 16, 1998, utilizing an electronic water probe capable of measuring with an accuracy of 1/100 of a foot Groundwater elevation data are presented in Table 2 ' 225 Groundwater Sampling-and Analysis On November 16, 1998, groundwater samples were collected from wells MW1, MW2, and MW3 ' The samples were collected after purging a minimum of three well volumes and stabilization of electric conductivity, pH, and temperature Field development/purge logs are presented in Appendix C Subsequent to purging, groundwater was sampled and transferred to appropriate sample containers, using clean, disposable bailers with bottom emptying devices to reduce volatilization Sample containers were then labeled with sample identification, placed on ice, and shipped under chain-of-custody to BC Laboratories The groundwater samples from wells MW1, MW2, and MW3 were analyzed by BC Laboratories for TPHg, BTEX, and oxygenate fuel additives A groundwater sample was collected from an on-site groundwater supply well (DW) The sample from well DW was analyzed for volatile organics by EPA Method 524 2 Groundwater analytical results are summarized in Table 3, and laboratory data sheets are presented in Appendix D 3.0 SUBSURFACE CONDITIONS ' 3_1 Geology Pea gravel fill material was encountered in soil boring MW 1 in the upper 7 feet of the soil column ' Soil from depths between 7 feet bgs and 41 to 45 feet bgs consisted of lean clay and clayey sand Soil from depths between 41 to 45 feet bgs and 46 5 to 50 feet bgs consisted of sandy elastic silt Soil from depths between 46 5 to 50 feet bgs and 61 5 to 65 feet bgs consisted of poorly graded sand and poorly graded sand with silt Soil from depths between 61 5 to 65 feet bgs and 66 5 to 70 feet bgs consisted of lean clay Soil from depths between 66 5 to 70 feet bgs and 70 5 feet bgs ' consisted of poorly graded sand Soil from depths between 70 5 feet bgs and 78 5 feet bgs consisted of lean clay Silt with sand was encountered in soil boring MW2 in the upper 6 to 10 feet of the soil column Soil from depths between 6 to 10 feet bgs and 16 feet bgs consisted of lean clay Soil from depths w\163931rgmr1s\summ doc 3 i