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This complicates the determination of whether any discovered contaminants are from on-site or off-site sources. 3) The critical question concerning the site is if any contaminants exist at the site, and whether any off-site sources of contaminants have migrated via groundwater to impact the site. Potential off- site sources of contaminants should be evaluated by testing up-gradient perimeter of groundwater sampling points. On-site sources of contaminants should be evaluated by random systematic sampling of soils and groundwater. The potential contaminants range from the spectrum of hydrocarbons (grease, oil, diesel and gasoline), to solvents and metals. Additionally, a geomagnetic survey would also reduce the risk associated with buried tanks,drums and other metal debris that could act as future sources of contamination while minimizing future surprise discoveries during construction activities. To lower the risk associated with the site, we recommend a Phase II Environmental Site Assessment be performed. This assessment should include at a minimum, the following field and analytical work: • On-site random systematic soil and groundwater sampling; • Up-gradient perimeter groundwater sampling; • On-site geomagnetic survey for buried metallic objects. All soil and groundwater samples should be analyzed for: • Hydrocarbons ranging from grease to gasoline; • Benzene,Toluene,Ethylbenzene,and total Xylenes; • Gasoline oxygenates and additives; • Volatile and Semivolatile Organic; • Cam 17 suite of Metals; • Poly Aromatic Hydrocarbons; • Poly Nuclear Aromatics; • Poly Chlorinated Biphenyls. Groundwater on site is located at approximately 26 feet below ground surface (bgs). WHF, Inc., Environmental Engineering Group (WHF) of Oakdale, CalifQrnia previously conducted a Phase 11 Site Assessment for the site dated March 16, 2001 for the Elks Lodge Property located at 317 South Center Street, Stockton, California. Please note that the site address of 317 S. Center Street pertains to Assessors Parcel Number (APN) 137-310-10, but the proper site address appears to be 339 S. Center Street, APN 137-310-12. WHF completed a boring to determine groundwater depth and soil and groundwater contamination (metals and hydrocarbons) on site. The following conclusions were made by WHR • The groundwater contains MTBE and gasoline above the acceptable limits. • Motor oil was present in groundwater at 23 mg/L; • The soil column at B-1 from 10"to 25' was free from contamination for those parameters analyzed except for the priority metals; • The priority metals are all below the maximum acceptable limits for both the groundwater and soil; • Groundwater was encountered at 26'below ground level; • There was an auto wrecking yard, ACME Auto Wrecking located at 325 South Center from 1949 to 1955. In 1955 to 1956 the business on this property became ACME Auto and Truck Parts. After 1956 the business no longer existed. In 1960 the site was cleared; • Oxygenates, including MTBE, were not used prior to 1975, therefore, it is logical to assume that the gasoline and MTBE contamination present in the groundwater underlying 42162.E01/ST04P141 Page 2 of 9 Copyright 2004,Kleinfelder,Inc. March 30,2004