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40 activities consisted of the advancement of seven soil probes(SB-1 through SB-7)and the collection of soil and in-situ ground water samples for laboratory analysis(Figure 2). Laboratory analysis of soil samples detected BTEX,TPH-d,TPH-g and methyl tertiary-butyl ether (MTBE) for samples collected from soil probe boring SB-5. In addition, relatively low concentrations of petroleum hydrocarbon compounds were detected for soil samples collected from SB-4 and SB-7. The analytical results of ground water samples collected from the soil probe borings suggested that ground water has been extensively impacted by BTEX,TPH-d,TPH-g and MTBE. The greatest petroleum hydrocarbon impacts to ground water were reported for soil probe boring locations SB-5 and SB-7 located north of the former diesel UST location. Laboratory analysis of ground water samples collected from soil probe SB-5 detected benzene (6,500 ppb), toluene (35,000 ppb), ethylbenzene(4,500 ppb),total xylenes(25,000 ppb), TPH-d(320,000 ppb),TPH-g (93,000 ppb), and MTBE (560 ppb). In April 1999, five soil borings(B-1 through B-5)were advanced,B-4 and B-5 were subsequently completed as monitoring wells MW-4 and MW-5,respectively, at locations down gradient(north) of previous soil probe boring SB-7 and the former UST locations,and soil boring B-1 was advanced at a location up gradient(south)of the former UST locations. Soil boring B-2 was advanced east of the former UST area to evaluate previously reported anomalous ground water analytical results in the vicinity of monitoring well MW-1 and soil probe boring SB-1. Soil borings B-3 was completed west ofprevious soil probe boring SB-6 and the former UST area.Soil borings B-1 through B-3 were advanced to a total depth of 15 feet bsg. Soil borings MW-4 and MW-5 were advanced to depths of 21 feet bsg and 17 feet bsg, respectively. During the soil boring activities, ground water samples were collected from soil borings B-1 through B-3 for laboratory analysis. There were no reported detections of BTEX, TPH-g, or TPH-d in soil samples collected from the five soil borings. Fuel oxygenating compound MTBE was detected at concentrations of 65 gg/mg and 110 gg/mg in soil samples collected from soil boring MW-4 at 17.5 and 20 feet bsg, respectively. Concentrations of TPH-d were detected in two of the eight ground water samples analyzed TPH-d was reported in samples B-2 and B-3 at concentrations of 570 µg/1 and 130 µg11,respectively. On 18,20 and 23 February and 08 March 2002,the soil borings(B8,B9 and B10)were advanced at the site. Boring B8 and B9 were sampled for the collection of discrete ground water. A HydroPunch water sampling assembly was advanced to a depth of 60 feet bsg in boring B8,also to a depth of 65 feet bsg in boring B8 without yielding water,and finally to a depth of 71 feet in boring B8 for collection of a grab ground water sample.A hydropunch water sampling assembly was also advanced to a depth of 60 feet bsg in boring B9 and finally to a depth of 70 feet in boring B9 for collection of a deeper grab ground water sample. Soil boring B9 was single-completed as ground water monitoring well MW-9 screened from 70 to 75 feet bsg. Soil boring B10 was single- completed as ground water monitoring well MW-10 screened from 55 to 60 feet bsg. MTBE was detected in the grab ground water sample collected at boring B8-55 and B9-55 at concentrations of 170µg/1 and 41 µg/1,respectively,by EPA Method 8020.MTBE was not detected in the grab ground sample collected from boring B8-70 by EPA Method 8260. However, a low concentration of MTBE was detected in the grab ground water sample collected at boring B8-70 at concentrations of 1.6µg/1,by EPA Method 8260.There were no reported detections of any other fuel oxygenating compounds. Advanced GeeftvironmentsL Inc.