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i l Chevron/S. El Dorado 13 August 199U analyzed for the presence of benzene, toluene, ethylbenzene, and -- xylenes (9TEX) , and for total petroleum hydrocarbons (TPH)-as- gasoline using modified U.S. Environmental Protection Agency (EPA) Methods 5030/8020/8015- copies of the analytical reports and chain-of-custody documents are included in Appendix H. on'torin Well Const t o . Groundwater-monitoring wells were installed in all three of the boreholes. The wells were constructed of clean, 2-inch diameter, 0.020-inch machine- _ slotted, Schedule 40 polyvinyl chloride (PVC) well screen and blank casing. A well filter pack consisting of No. 2 Monterey sand was placed in the annular space in each well from the bottom of the borehole to at least 5-feet above the top of the screened interval. A 2-foot-thick layer of hydrated bentonite pellets has oy set above the filter pack and the wells then sealed to grade surface with cement grout. The wellheads were equipped with locking plugs and encased in traffic-rated EMCO/Wheaton street. boxes for protection. The three wells were completed to a depth of aper-�xirnately 60-feet below grade. Well construction details r , are presented on the drill logs in Appendix F. onitor n Well Uevelo went. Standard Groundwater Technology well development procedures require new wells to be developed using a combination of bailing, surging, and pumping, as needed. On Rugust 20, 1990, Groundwater Technology employed a truck-mounted surge-block and bailer system to develop the three wells. Each of the wells yielded approximately 100-gallons of water before a sufficiently low level of suspended sediments in the extracted water was obtained. None of the wells bailed dry .r during development. The water generated during well development -placed__in_ 55.^galIon_steel drums and held an site pending proper disposal. GNB�I'\U11,1TF:H ti 1'fc�{unaK:v,IAC.