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Drawdown data collected from monitor wells MW2 and MW3 Indicated that the pumping had very little Influence on depth to water in these wells at approximate distances of 80 and 100 feet, respectively Monitor well MW4 however, exhibited a maximum of approximately 0 5 feet of drawdown during the 24 hour pumping operation Although 24 hours lapsed before drawdown appeared to stabilize at 0 5 feet, recharge of groundwater to its original static level in monitor well MW4 occurred in approximately 6 hours (Figure F2) The relatively rapid drawdown of the pumping well MW 1, the slow continuous pump rate of 0 25 gallons/minute, and the relatively slow recharge rate of 0 3 gallons/minute, Imply that the groundwater-bearing zone at approximately 20 feet below ground surface at the site is narrow and exhibits low hydraulic conductivity Groundwater generated during the pump test was contained in 6,900-gallon aboveground tank and left onsite The owner/client contracted directly with Nor-Cal to pump and dispose the water in a proper manner 6.0 CONCLUSIONS Data collected during this phase of the environmental Investigation indicated that the highest concentrations of contamination are confined mainly to the area directly beneath the site, and that subsurface contamination, apparently from the site, is present to a lesser degree between 100 and 200 feet west and southwest of the site Contamination extending offsite at distances greater than approximately 50 feet appears to be confined mainly to the capillary fringe zone or "smear" zone This smear zone is believed to be approximately 5 feet thick between the depths of approximately 15 and 20 feet and likely resulted from historic fluctuations (overall decrease) in groundwater elevation Based on this Information, it is assumed that during the years following the release of petroleum hydrocarbons to the subsurface, groundwater was likely closer to 15 feet below the ground surface and flowed in a southwesterly direction 6.1 Summary A total of fifteen soil borings were completed at the site during this phase of the environmental investigation conducted by SF 4COR,three of these borings were converted to groundwater monitor wells, one was converted to a vapor extraction well, and three were used as temporary vapor extraction/observation wells The remaining eight borings were drilled to groundwater where groundwater grab samples and soil samples were collected for the purpose of delineating the lateral extent of contamination Laboratory data from this sampling and analysis program provided information to adequately define the extent of subsurface contamination 6 1 1 Soil Contamination Laboratory results of soil samples collected at the site during this phase of the environmental Investigation indicated that only low to moderate concentrations of TPHg exist in the capillary fringe zone directly above groundwater Field observations however, indicated that vadose zone soils were SEACOR 014-41-1 par 19