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1✓ �I <br /> the aquifer strata has been defined, the casing will be lowered to the bottom of the <br /> borehole, leaving a slotted interval above the occurrence of groundwater to observe for <br /> floating product. The sand pack will be placed to a point about two feet above the slots. A <br /> bentonite seal will be placed atop the sand pack, and a cement grout seal placed atop the <br /> bentonite using a trerrue line, filling from the bottom to top of the borehole. A traffic rated <br /> well head access box and security device will complete the well. <br /> Monitoring Well SaWling and Development All monitoring wells will be developed to <br /> remove the drilling muck, grade the sand pack and provide a more complete hydraulic <br /> connection to the aquifer. A well development log will be kept of the well volumes <br /> removed until the water becomes clear and the amount of sand pumped is minimal. The <br /> well will be allowed to recover for at least 72 hours prior to sampling. The well casing will <br /> be surveyed to a known datum to accurately measure groundwater elevation contours. <br /> Chemical Analysis <br /> Up to six (6) capillary fringe soil samples, one (1) aquitard sample and six (6) groundwater <br /> samples will be analyzed at a State certified analytical laboratory from the exploratory <br /> borings. These samples will be tested for the following; Total Petroleum Hydrocarbons as <br /> Gasoline (TPHG), Benzene (B), Toluene (T), Ethylbenzene (E) and Xylene (X), Methyl- <br /> tert-butyl-ether(MTBE) and fuel oxygenates, 1,2 Dichloroethane and Ethylene Dibromide <br /> using EPA Methods 351018015, 8020, 8240 and 8260. The analyses will be run on an <br /> "normal" turnaround (five working days). <br /> Report <br /> A Preliminary Site Assessment Investigation Report will be prepared for submittal to the <br /> City of Tracy, which would be forwarded to the PHS EHD. The report will include the <br /> field methods, permits, exploratory boring logs, chemical analytical data and report <br /> narrative of site hydrogeology and contaminant distribution, and conclusions and <br /> recommendations for further work (including groundwater monitoring wells and quarterly <br /> sampling plan approach), if needed. <br /> If you have any questions, please call. p QFO <br /> Sincerely, N, pQ\0 M. P �O <br /> Wright Environmental Services, Inc. �315 <br /> U N° 1262 —a <br /> GERMED <br /> � y"1•(N E��GIiiEERIfiIG <br /> ohn Lynch Christopher M. Palmer sl KUNST <br /> President HG 246, CEG 1262 <br /> �� OF cauF°� <br /> Attachments: Figure 1. Proposed Boring Location Map <br /> Wright Environmental Sampling and Well Installation Protocols <br /> Page 3 <br />