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~Y i Page 2 FIELD EXCAVATION ACTIVITIES The four USTs, associated product lines, sump and hoists were removed on May 20, 1993 . Tank removal and sampling was witnessed by William Snavely, an inspector and representative of San Joaquin County Department of Public Health, Environmental Health Division, and Mark Miller representing Chevron U. S.A. Products Company. No holes were observed in the gasoline USTs, lines or waste oil tank. Groundwater was encountered at approximately 8 feet below grade in the UST excavations . SOIL SAMPLING All soil samples were collected under the direction of William Snavely. Soil samples were collected in clean six- inch-long brass tubes (2" in diameter) . Tubes were covered at both ends with aluminum foil and sealed with plastic end caps. The soil samples were then labeled, recorded on a Chain-of-Custody form, put in a cooler with crushed ice and transported to Superior Precision Analytical, Inc. located in San Francisco, California. UST Excavation Sampling Soil samples designated A-W, A-E, B-W, B-E, C-W, and C-E were collected from the fuel UST excavation sidewalls in the native soil near each end of the tanks at approximately 7 feet below grade. Soil samples designated UST-N and UST-S werecollected from the north and south excavation sidewalls also at approximately 7 feet below grade. The approximate sample locations are shown on Figure 2 . An excavator bucket was used to collect a sample from each location. The samples were collected by removing the top 3" to 6" of soil in the bucket, then pushing a brass tube into the soil until completely filled, and handled as previously described. Grab samples from the groundwater in the fuel UST excavation were collected in four 40 ml Volatile Organic Analysis (VOA) vials (laboratory supplied with Hcl preservative) and one 1 liter amber glass bottle. Samples were collected by removing the caps approximately 4 to 6 inches beneath the water surface until bottles were full then tightening the caps . Samples were checked to be sure no headspace was left in the VOAs.