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1) Former Jackpot Gas - 510 North Main Street: This property is located approximately 1,100 feet north of the subject site at the northeast corner of Main and Alameda Streets. In 1985, three fuel underground storage tanks were removed from the property. An Unauthorized Tank Release of petroleum, based on visual evidence of soil contamination upon tank removal, was reported to the EHS in August 1989. Contaminated soil (approximately 900 cubic yards) was removed at the tank locations in 1990. It was aerated on site prior to back-filling in the hole. Laboratory Analyses had detected the presence of benzene, toluene, xylene, and ethyl benzene (BTXE) in the soil. Following soil removal, two groundwater investigations were performed and six groundwater monitoring wells were installed on site. Depth to on-site groundwater was determined to be between 24 and 26 feet and the groundwater gradient was determined to be northerly to northeasterly. Analyses of groundwater revealed low concentrations of BTXE (at or below 15 micrograms per liter) in four of the six wells (the remaining two wells showed non-detectable levels). Based on the low concentration, groundwater remediation was not deemed economically feasible by the lead agency, EHS. Therefore, an order was given by the State Water Resources Control Board (WRCB) in 1991 to begin quarterly groundwater monitoring for one year, upon which the situation would be reassessed. Quarterly groundwater monitoring, conducted by WHF Environmental Consultants of Modesto, California, began in May 1991 and is still ongoing. However, only three of the wells (on the south side of the site) have shown detectable amounts of contaminants in the last three quarterly sampling series. A vapor extraction system for the well showing the highest levels (Well #2) was installed in September 1992. The latest round of groundwater sampling (November 4, 1992), identified non-detectable levels of contaminants in the three wells. 11