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77 16 February 1999 AGE-NC Project No. 98-0534 Page 4 of 7 2.4. GROUND WATER DEPTH AND FLOW DIRECTION Based on the San Joaquin County Flood Control District and Water Conservation District Lines of Equal Depth of Water Wells Fall 1996 map, the estimated depth to ground water in the vicinity of the site is 10 and 20 feet below surface grade(bsg). However, significant ground water recharge has occurred during 1994 through 1998 and ground water depth at the site may be more shallow than estimated in 1996. Based upon data obtained from nearby sites, the prevailing ground water flow direction in the vicinity of the site is estimated to be north. However, flow direction may be both locally and seasonably variable. The Stockton Deep Water Channel is the nearest surface water feature to the property, located approximately 1,750 feet north of the site. Water from the channel drains into the San Joaquin River and is primarily used for commercial and recreational boating, with agricultural as a secondary use. The channel contains water continually and has a potential tidal effect upon ground water depth or flow direction in the area. Based upon information obtained from the UST removal, ground water is currently at a depth of approximately 15 feet below surface grade (bsg). 3.0. SCOPE OF WORK Based on the laboratory analysis of soil samples collected and field observations noted during UST system removal,petroleum hydrocarbon impacts to soil appear to be located beneath the former fuel dispenser island and localized on the product line trench approximately mid-way through the lines run from the USTs to the dispensers. Petroleum was also detected in the soil beneath the UST and in the ground water at the UST excavation. The UST area and ground water contamination will be assess with a later investigation. The proposed interim soil remediation scope of work will include the following tasks: • Pre-field work activities; • Soil excavation and backfilling; • Soil sample collection and analysis; • Soil stockpiled for transportation/disposal or treatment; and • Report preparation. Adranced CeoEnvironmenlal,Inc.