SITE INFORMATION AND CORRESPONDENCE

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Adjacent properties are aeronautic-related facilities. Existing facilities are shown on Figure 2, Site Vicinity Map (Appendix I). 3.2 Geology and Hydrology Stockton is located in the northern part of the Great Valley Geomorphic Province of California. Sediments in the area consist of Quaternary alluvium comprised of silts, clays and sands. The depth to groundwater in the vicinity of the subject property is reported to be approximately 50 feet bgs. The groundwater flow direction is reported to be to the west-southwest. Groundwater was not encountered in any of the soil borings. 3.3 Site History CRC conducted a Phase I Environmental Assessment of the subject property in June 1994. The CRC Phase I report dated July 18, 1994 discussed the site history from reviews of records at the San Joaquin County Building Department and historical aerial photographs. Files reviewed at the San Joaquin County Department of Health Services indicated that three (3) underground storage tanks (USTs) were removed from the site on July 10, 1989. The USTs consisted of two (2) 12,000-gallon tanks and one 10,000-gallon tank. One 12,000-gallon tank contained aviation fuel and the other two (2) tanks contained unleaded gasoline. The tanks and piping were removed and disposed. Tests on soils under the tanks indicated that detected petroleum hydrocarbons were within permissible regulatory limits. One additional 10,000- gallon tank was removed on May 27, 1993. Soil tests indicated minor amounts of gasoline constituents. The contaminated soil was excavated and removed. Tank closure was granted by the County o Meced on May 4, 1994. The aerial photograph review indicated that the subject property was agricultural land in 1937. Army barracks were located at the site from at least 1952 through 1975. The property was developed between 1981 and 1982. A two-story, three- room condominium with an indoor jacuzzi is attached to the airplane hangar. The facility was formerly used as an executive flight center. The condominium was apparently used for lodging by the pilots. 4.0 SUMMARY OF PHASE II FIELD OPERATIONS 4.1 Soil Boring and Soil Sampling Procedures Seven (7) soil borings (B1 through B7) were drilled on November 30, 1994 to a depth of 15 feet bgs. Four (4) borings were drilled around the airplane wash clarifier and three (3) borings were drilled near the car wash clarifier. Drilling access limited the boring locations near the car wash clarifier to three (3) borings CRC Environmental Risk Management,Inc. Project#2100-247-5 American Savings Bank 1888 Lockheed Court February 13, 1995 3 Stockton,California