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Soil Quality <br /> Soil contamination from petroleum hydrocarbons was found in several areas of <br /> varying depth and concentrations Levels of BTEX were detected in previous <br /> exploration in the 10 to 15 FT bgs zone along the east fence at less than 100 ug/kg <br /> and at a deeper 25 FT bgs at levels of 688 ug/kg of Xylene During earlier testing in <br /> March 1999, Galardo identified considerable BTEX in BH No B-1 in the vicinity of <br /> later installed MW No 1 and in BH No 2 near the east fence <br /> Diesel contaminated soil was found near MW No 4 particularly in the 25 to 30 FT bgs <br /> rzone and MW No 2 near the east fence in June 2002 Earlier bonngs by Gallardo and <br /> Barber found diesel at the 13,000 to 15,000 mg/kg levels in the same area <br /> Earner bonngs by Gallardo and Barber found concentrations of upwards to 30,000 <br /> mg/kg in the vicinity of MW No 1 and BH No B-1 at similar depths <br /> Review of previous geological findings and field findings in June supported the <br /> contention that there was dispersion of diesel in the 25 FT to 35 FT bgs zone atop an <br /> aquatard, possibly with earner perched waters Perched waters were not found at this <br /> depth by Stellar or Barber in December 2000 or the later June 2002 exploration <br /> Near the east fence during construction of MW No 2 in June 2002, minor seepage of <br /> product (diesel like) and shallow water were apparent in the upper 0 to 10 FT bgs <br /> stratum <br /> rRECOMMENDATIONS <br /> Groundwater monitoring should continue in the near term Use of common elevation <br /> datum between the WOS and Victor Fine Foods Company studies and assignment of <br /> elevations to groundwater surface should be continued <br /> iAttenuation of hydrocarbons in the groundwater is apparent, however, low levels <br /> identified in Cone Penetration Sampling in May 2004 found north of MW 3 may a <br /> broader leading edge of the plume There has been a continued directed effort to <br /> establish a Non-detect or"Clean Line" beyond the plume boundary to better estimate <br /> residual The 150 mg/ltr finding in ground water further to the west of earlier sampling <br /> 1 is slightly higher than the hoped for Non-detect level but approaches the desired <br /> "Clean Line" level and may not warrant the additional cost of further boring <br /> Altemative remediation plans of contaminated soil in the vicinity of MW No 2 should <br /> be considered leading to development of an approved work plan and closure of the <br /> site <br /> Seek guidance from EHS and submit"GeoTracker" formatted information on findings <br /> . and MW locations for electronic data submittal requirement to State of California <br /> 1 <br /> 5 <br />