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1 On 02 August 2001, three ground water monitoring wells (MW-1, MW-2 and MW-3), screened between 20 and 40 feet bsg, were installed at the site (Figure 2) Well MW-1 was installed at the ' northeast corner of the site, and wells MW-2 and MW-3 were installed at the southern edge of the dissolved plume area Two ground water monitoring events have occurred to date, the last one in January 2002 ' 0 Ground water elevation at the site is approximately 15 feet below mean sea level Ground water at the site is inferred to flow north-northeast ' 0 TPH-g,TPH-d and BTEX compounds have not been detected in ground water samples from wells MW-2 and MW-3 I TPH-g and TPH-d have been detected in well MW-1, the highest concentrations were detected during the January 2002 monitoring event at 18,000 µg/l and 9,000 µg/l, respectively I0 BTEX compounds were detected in well MW-1 during the January 2002 monitoring event at concentrations of 360 µg/1 benzene, 1,600 gg/l ethylbenzene and 4,700 µg/1 xylenes, toluene was not detected during the January 2002 monitoring event,but was detected during the preceding September 2001 monitoring event at 160 gg/1 • MTBE was detected in the monitoring well sample from well MW-2 at a maximum ' concentration of 9 3 µg11 On 09 to 11 April 2003, five soil borings (CPT-1 to CPT5)were advanced on-and off-site utilizing CPT technology, at each boring location, lithologic data was collected from the initial CPT boring, an immediately adjacent twin boring was then advanced at each CPT location to collect grab ground water samples from selected depths The objective ofthe investigation was to model the geologic and hydrogeologic frameworks and to assess potential dissolved petroleum-migration pathways beneath the site Soil borings for sounding were as follows • CPT 1 was established in the vicinity of monitoring well MW-1 and soil borings A and I to a depth of 150 feet below surface grade (bsg), I0 CPT2 was established in the vicinity of soil borings B and J to a depth of 160 feet bsg, • CPT-3 was established west of boring C to a depth of 160 feet bsg, I0 CPT-4 was established south of monitoring well MW-1 and soil borings E and G to a depth of 150 feet bsg, and ' 0 CPT5 was advanced at the northeast corner of the intersection of California Street and Miner Avenue to total depths of 160 bsg Ground water and soil samples were collected from CPT boring locations at the following intervals • CPT-1 was sampled between 96 and 100 feet bsg,between 120 and 124 feet bsg and between 146 feet and 150 feet bsg, • CPT-2 was sampled between 93 and 97 feet bsg,between 120 and 124 feet and between 146 and 150 feet bsg and between 181 and 185 feet bsg,