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