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