Laserfiche WebLink
i <br /> Feasthility Study Report <br /> 1140 W Hammer Lane, Stockton, CA <br /> i <br /> 9.0 PROPOSED SCOPE OF WORK <br /> 9.1 Well Destruction <br /> Ground Zero will subrrut a workplan for well destruction, if PHS/EHD concurs with our <br /> recommendation to destroy wells MW6 and MW7 The wells would be purged and sampled prior to <br /> destruction The wells would be destroyed under permit from PHS/EHD by pressure grouting with <br /> neat cement The well box and casing for well MW6 would be removed to approximately 3-5 feet bgs <br /> and the grout would be allowed to spill over into the void prior to backfilling to the surface with native <br /> soil Due to its location within the paved parking lot, the well box for well MW7 would remain in <br /> place and the void between the casing and the well box would be filled with neat cement <br /> 9.2 ORC Installation <br /> Ground Zero will install ORC filter socks in wells MW 1, MW3 and MW5 in order to introduce oxygen <br /> into to the saturated zone at locations upgradient of the plume (MW3), within the plume (MW5), and <br /> at the downgradient extent of the plume (MW I) The ORC filter socks will be placed in the wells <br /> during the 3'a quarter of 2001 (August) The ORC filter socks will be replaced with fresh filter socks <br /> after approximately 6 months Groundwater conditions and the efficacy of enhanced bioremediation <br /> with ORC will be re-evaluated after a period of one year <br /> 9.3 Groundwater Monitoring <br /> Ground Zero will collect groundwater samples from wells MW 1, MW3, and MW5 immediately prior <br /> to installing the ORC filter socks In additional to routine analyses for gasoline constituents, the wells <br />' will also be evaluated for physical parameters indicative of intrinsic bioremediation (dissolved oxygen, <br /> oxidation-reduction potential, etc) All site wells (with the exception of MW6 and MW7) would be <br /> Isampled on a semi-annual basis for gasoline constituents As discussed in section 9 1 of this report, <br /> wells MW6 and MW7 would be properly destroyed under permit issued by PHS/EHD Ground Zero <br /> Iwill prepare a groundwater morutoring and sampling report on a semiannual basis and subrrut the <br /> reports to the appropriate regulatory agencies <br /> I <br /> G 1Dat-\(,R01TNDZE\KN0W1_J% HAWRI N)R1%V,wgibi dyRcpon dog <br /> 19 <br />