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• 2.2 Monitoring Wells <br /> -� The three soil borings were completed as two inch diameter <br /> monitoring wells. Specific details of the well <br /> completion/construction are included on the boring logs (Appendix <br /> I ) . After completion, the depth to groundwater was measured <br /> using a conductivity probe. <br /> The three montorng were developed by pumping at a rate of <br /> 1.4 gallons per minute (gpm) for a period of 45 minutes in order <br /> to remove at least four well volumes (casing plus sandpack) . <br /> Groundwater samples were collected using a teflon bailer with a <br /> bottom emptying device. The samples were contained, preserved <br /> and transported to Squo �ialyt�ica1brars, a state <br /> _ certified hazardous waste laboratory, in accordance with EPA <br /> protocol. Ttae ss�mp; esr wee nalyzeg, fa TB xa �jTPH t3asta -ne <br /> _ ami:,Adie►seL��byE.P.A��,met�hca�s,��0158a2_ �: <br /> 3.0 SUBSURFACE CONDITIONS <br /> 3. 1 Field Inspection <br /> The soils encountered during drilling consisted predominantly of <br /> lean clays to about six feet, sands to 12 feet, silt to 16 feet, <br /> sands to 20 feet and fat clays from 20 feet to the bottom of each <br /> boring. Saturated soils were recorded detected at about 10 feet <br /> _._ below grade. Water levels stabilized slightly above this depth <br /> �., in the wells. <br /> • "�` Hydrocarbon odors were not detected in the soils borings during <br /> drilling. <br /> - The shallow groundwater gradient was calculated using surveyed <br /> wellhead elevations and multiple depth-to-water measurements <br /> (Table 1 ) . Monitorings in August and September 1989 indicate the <br /> groundwater gradient is generally south to southwesterly at <br /> approximately 51 feet/mile ( 0.01 ) , and is affected by tidal <br /> fluctuations (Figures 3 and 4) . <br /> 3.2 Laboratory Analysis - Soils <br /> The laboratory analysis of the S and 8 foot samples for each <br /> boring reported non-detectable concentrations of BTEX & TPH as <br /> gasoline and diesel. The sample analysis of hydrocarbon <br /> constituents for the borings are summarized in Table 2. The <br /> laboratory data sheets and chain-of-custody form are presented in <br /> _ Appendix II. <br /> 3.3 Laboratory Analysis - Groundwater <br /> Laboratory analysis of groundwater samples recorded detectable <br /> levels of TPH as diesel hydrocarbons in MW2 and MW3. BTEX or TPH <br /> as gasoline were not detected in all three wells. The water <br /> sampling results are summarized in Table 3. The laboratory data <br /> sheets and chain-of-custody form are contained in Appendix III . <br /> . .. 2 <br />