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I Ire. tion and the soil sample analytical results are contained in WESTDN's January 31, 1940 "Boil Remediation Proposal." Included with the soil samples, a single water sample was collected through the annulus of the hollow stem auger. The analytical data for this water sample indicated the lack of petroleum hydrocarbon compounds. _ fill ..7Z�G .u�>, ii1•([� T:�:f�;, J fie. This data was not considered representative, by the San Joaquin County Public Health services, Environmental Health Division (PHS/EHD) , since it was not collected from a properly installed and developed monitoring well. Therefore, prior to issuance oL closure documentation for the site the PHS/EHD has requested that a single. monitoring well be installed within lot of the groundwater down-gradient direction of the center of the tank T2 area. 7.0 Proposed Work Plan 1 In order to adequately address the PHS/EHD concerns, a single monitoring well will be installed at the site. The following narrative describes the proposed site activities: 7.1 Well Siting The monitor well, identified as MW-1 will consist of one shallow monitoring well. The well will be located directly north of the M borehole location as shown on Figure 5. This well placement has been selected to investigate the possibility of petroleum hydr:scar- bon concentrations in groundwater beneath the site. The final well placement will not differ significantly from the position as shown in Figure 5. 7.2 Well Installation As the anticipated depth to water is no more than 50 feet below groind surface (BGS) and the maximum drilled depth at the well location will not exceed 60 feet BGS.- The well will be installed using hollow stem auger drilling techniques. This shallow well is projected to have a total depth of about 60 feet BGS, with the screened zone extending from ifivewfeeta-aboVe the water table to the -" total depth of the well (set at approximately..tent-feat-berloyrnt.he water table) . The projected total depth of the well was determined based on a previous drilling log as to accurately place the screened zone across the groundwater surface. The lithologic information necessary for the accurate vertical placement of the screened zone in the well was obtained during the drilling of the adjacent soil boring location (see Figure 5) . No soil sampling will be conducted ---.-- The well casing will be constructed of four inch diameter, flush threaded, schedule 40 PVC pipe. The screen will be 15 feet long and composed of factory slotted, four inch diameter, flush 7 -