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Soil _ ampling <br /> Shallow soil borings will be drilled using a truck-mounted hollow-stem <br /> auger drilling rig, unless site conditions favor a different drilling method. <br /> Drilling and sampling methods will be consistent with ASTM Method D- <br /> 1452-80. The auger size will be a minimum 6-inch nominal outside- <br /> diameter(O.D.) No drilling fluids will be used during this drilling method. <br /> The augers and other tools used in the bore hole will be steam cleaned <br /> before use and between borings to minimize the possibility of cross- <br /> contamination between borings. <br /> Soil samples are typically collected at 5-foot intervals as a minimum from <br /> ground surface to total depth of boring. Additional soils samples will be <br /> collected based on significant lithologic changes and/or potential chemical <br /> content. Soil samples from each sampling interval will be lithologically <br /> described by an Enviros geologist. Soil colors will be described using the <br /> Munsell Color Chart. Rock units will be logged using appropriate lithologic <br /> terms, and colors described by the G.S.A. Rock Color Chart. <br /> Head-space analyses will be performed to check for the evidence of volatile <br /> organic compounds. Head-space analyses will be performed using an <br /> organic vapor analyzer; either an OVA, HNU, or OVM. Organic vapor <br /> concentrations will be recorded on the Enviros field log of boring. The <br /> selection of soil samples for chemical analysis are typically based on the <br /> following criteria: <br /> 1) Soil discoloration <br /> 2) Soil odors <br /> 3) Visual confirmation of chemical in soil <br /> 4) Depth with respect to underground tanks (or existing grade) <br /> 5) Depth with respect to ground water <br /> 6) OVM reading <br /> Soil samples selected for chemical analysis are covered with teflon tape and <br /> the ends are capped to prevent volatilization. The samples are labeled and <br /> entered on a chain-of-custody form, and placed in a cooler on ice for <br /> transport to a State-certified analytical laboratory. <br /> Soil cuttings are stockpiled on-site. Soils are sampled and analyzed for site- <br /> specific chemical parameters. Disposition of soils is dependent of chemical <br /> analytical results of the samples. <br /> Soil borings not converted to monitoring wells will be backfilled (sealed) to <br /> ground surface using either a neat cement or cement-bentonite grout <br /> mixture. Backfilling will be tremied by continuously pumping grout from <br /> the bottom to the top of the boring where depth exceeds 20'or as required <br /> by local permit requirements. <br /> enviros® <br />