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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 monitoring wells 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 Sequoia Analytical Laboratories, a state <br /> rz'a certified hazardous waste laboratory, in accordance with EPA <br /> protocol Eampku.�spor,ana}� dorBEoridTPi $�4riM <br /> gni <br /> a�dd�i�e�e l> i�y' Ef2�1me t:hi�r�ds�>°8 E11f5:�8�Qt2,� <br /> 3 . 0 SUBSURFACE CONDITIONS <br /> pry <br /> 3 . 1 Field Inspection y <br /> The soils P encountered during drilling consisted <br /> predominantly of <br /> ( lean clays to about six feet, sands to 12 feet, silt to 16 fEct, <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 ind`idate `the <br /> groundwater gradient is generally south to southwestex<Iy 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 5 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 /> 4 <br /> laboratory data sheets and chain-of-custody form are presented in k <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 . HTEX 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 />