SITE INFORMATION AND CORRESPONDENCE CASE 1

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Phase One Environmental Inc. �✓ '�'' Page 2 Bank of Stockton-Cutter Project 102.2 August 23, 1996 , and the LOP is not requiring and engineered remedial work in the area of the excavated tanks which are now in the UST Fund. During 1995, a remedial feasibility plan was requested by the LOP, and a Work Plan for the feasibility study was prepared by Geological Technics Inc. Due to the changes in the way the State is handling low risk sites, and the very low residual levels of contamination, the LOP no longer believes engineered remedial action is necessary for this site. New information has been developed that poses complications, however. During a routine monitoring event involving the existing groundwater monitoring wells (4h Quarter 1995), a domestic water well on the Property was sampled and tested at the direction of the LOP. The water sample from the domestic well was found to contain gasoline range petroleum hydrocarbons and BTEX compounds. The water well is situated on the same Property as the former tanks were on and it lies several hundred feet to the north of the original tank pit. Summary of Recent Assessment Work In an attempt to determine if there could be a source for groundwater contamination other than the known USTs, Geological Technics Inc., Modesto California performed a records search. Records were found in the files of the LOP and the County Assessor's Office that suggested previously unknown above and below ground fuel storage tanks had once been located on the Property at a location about 40 to 50 feet from the domestic water well and about 350 feet from the known UST site. These records suggested there had once been a 1,000 gallon gasoline UST and at least two diesel AST's as well at pumps for delivering the fuel to vehicles. In order to help determine if the UST may have leaked and impacted the water well, Geological Technics Inc. installed 5 shallow soil borings in the vicinity of the former tanks. It was found that a former 1,000 gasoline UST had been removed and the pit was backfilled to a depth of 7 feet. Beyond the confines of the fill material, gasoline was found in significant quantities below, and around the former tank pit. Geological Technics concluded there is a reasonable likelihood the former gasoline UST released gasoline which migrated to the shallow groundwater (at about 35 feet below ground level) and has impacted the water well. It appears that additional site characterization will be needed to assess the extent of impact to the soil and groundwater. It is possible engineered remedial action may also be needed to assure public health and the environment is protected. Request for UST Fund Coverage We request the USTCFP grant coverage under the exiting claim for reimbursement of expenses incurred by the Bank of Stockton related characterization and possible remedial action of the newly discovered former leaking gasoline UST. We believe this action is appropriate for the following reasons: