SITE INFORMATION AND CORRESPONDENCE CASE 1

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Page 2 USTCFP Pre-Approval Request Bank of Stockton-Cutter Project 102.2 November 20, 1996 During a routine monitoring event involving the existing groundwater monitoring wells (4`h 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, and it lies several hundred feet to the north of the original tank pit. In an attempt to determine if there could be a source for groundwater contamination other than the three 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. The borings were sufficient to identify the location of the tank pit by the presence of fill material to a depth of seven 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 are protected. In a letter dated August 23, 1996, we requested 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. In a telephone conversation with you on October 1, 1996, you informed me that the work related to the former gasoline UST will be covered under the exiting claim (#1878), but that the work related to the former diesel ASTs are not covered. At this time it is not known how much of the work should be allocated to the gasoline UST, however, since only one of the five shallow soil borings performed to date encountered diesel impacted soil, we assume at least 80 percent of the work will be related to the UST. II. Outline the Proposed Preliminary Site Characterization Work. As a first step in completing the characterization of the vertical and lateral extent of impacted soil and groundwater, we have proposed to drill a suite of eight soil borings in the vicinity of the former gasoline UST. The borings are intended to penetrate the capillary fringe zone at a depth of about 35 feet.