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• One boring would be located in the center of the former UST location and the other two borings would be located in the presumed downgradient direction (direction of groundwater flow is northeast) from the former UST All bonngs would be advanced to a depth of 40 feet below ground surface (bgs) Subsequent to sampling, soil bonngs will be backfilled to surface using hydrated bentonite or neat cement grout Sod samples would be collected every 5 feet for logging purposes and subjective analysis using a photoiomzation detector (PID) Up to two sod samples per boring, based on evidence of soil contamination (odor, discoloration, PID readings) and/or hthology would be submitted to a State- certified laboratory for analysis The samples would be analyzed for total petroleum hydrocarbons as gasoline, diesel, and kerosene (TPHg, TPHd, and TPHk, respectively) using modified EPA method 8015, and benzene, toluene, ethylbenzene, total xylenes (BTEX), and methyl tert-butyl ether (MTBE) using EPA method 8020 as required by PHS/EHD Ground Zero will prepare a technical report summarizing the results of the investigation The report will include a description of methodologies, assumptions, findings, conclusions, recommendations, QA/QC procedures, and any other pertinent discussion. The report will compare analytical results to applicable federal, state, and local reporting/clean up levels The report will also include supporting materials such as a site plan showing boring locations, tabulated analytical results, etc . Discussion of Feld Methods Ground Zero considered two methodologies for advancing soil bonngs and collecting soil samples. Soil bonngs could be advanced using a drilling ng with hollow stem augers or using the direct push methodology The hollow stem auger drilling method utilizes traditional 6-inch to 8-inch diameter drilling augers which moves soil from the subsurface to the surface along the flighted augers where it must be contained in drums or covered with plastic until laboratory results are received Soil disposal options can then be considered Soil disposal options include aeration on site under permit from the Au Pollution Control District or disposal at an off site landfill The advantage of direct push technology is that little or no soil cuttings are generated Instead, the small diameter rods are pushed and/or hammered to the desired depth and no soil cuttings are brought to the surface, thereby eliminating soil storage and disposal costs However, direct push technology is typically limited to approximately 45 to 60 feet in depth, depending on hthology Based on the discussion above, Ground Zero recommends utilizing the direct push method which, if successful, will result in lower cost due to reduced time on site and eliminating soil disposal costs However, if subsurface conditions preclude the use of direct push technology, Ground Zero would reschedule field activities using a hollow stem auger ng propmaAdieae12 doc