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maximum possible sum of these scores is 50. A high summed score indicates low likelihood of contaminants reaching ground water. In such cases, a high LUFT maximum allowable concentration is permitted. Soil with concentrations greater than the LUFT maximum allowable concentration must be remediated. Tables 3 and 4 separately list the site characteristics for contaminants either in soil or bedrock. Geologic data has been interpreted from Taffet et al., (1990). Characteristics for the diesel-containing soil beneath the tank excavation are scored in Table 3. The soil sample with the maximum reported TEPH-diesel concentration is used to characterize all the soil at the tank excavation. This sample was collected from borehole U850-DlUl-10 at an elevation of 1,317 ft (5 ft above the bedrock contact) and yielded the a TEPH-diesel concentration of 9,000 ppm. Table 3. Site characteristics and scores for diesel-containing soil. Site characteristic Score 1. The minimum depth to ground water from the soil sample with 9,000 ppm 5 TEPH-diesel is approximately 42 ft. 2. Subsurface fractures are likely to exist in the bedrock that underlies the tank 5 excavation. 3. The average annual precipitation is 10.87 in. 9 4. No man-made conduits such as utility lines exist. 10 5. No unique site feature such as coarse sand or an adjacent recharge area exists. 1g Total 39 Table 4. Site characteristics and scores for diesel-containing bedrock Site characteristic Score 1. The minimum depth to ground water from the soil sample with 29 ppm TEPH-diesel 5 is approximately 28 ft. 2. Subsurface fractures are likely to exist in the bedrock that underlies the tank 5 excavation. 3. The average annual precipitation is 10.87 in. 9 4. No man-made conduits such as utility lines exist. 10 5. No unique site feature such as coarse sand or an adjacent recharge area exists. 1Q Total 39 The score of 39 for diesel-containing soil falls into the "high leaching potential" classification. The LUFT maximum allowable concentration for this classification for TEPH-diesel is 100 ppm and concentrations of BTEX must be non-detectable (ND). Since the TEPH-diesel concentration exceeds these levels, the soil must be remediated. 17