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I �I Site Background Information: Stallworth Auto Sales 1 Page 5 of 9 water samples collected from CPT-2. • 1 ,2-DCA was detected in the water samples collected only from CPT-3 at concentrations of 37 µg/1 in HU8 and 23 µg/1 in HU9/10. II On 18, 19 and 20 January 2006, one soil boring was advanced and two deep ground water monitoring wells (MW- 1C and MW- 1D) were installed at the site. A CME-95 truck-mounted drill rig was utilized to advance soil borings B-4, MW- 1C and MW-1D to total depths of 150 feet below surface grade (bsg), 135 feet bsg and 150 feet bsg, respectively, using 84nch diameter hollow-stem augers. Soil samples were not collected in borings MW- 1C and MW- 11). No soil samples were collected in boring B4 until 50 feet bsg. hi addition, ground water samples were collected from wells MW- 1C and MW-1D. Pilot borings MW- 1C and MW- 1D were completed as ground water monitoring wells of the same designations using 24nch diameter polyvinylchloride (PVC) casing with 0 .010-inch slotted screen installed from 125 feet to 135 feet bsg and 140 to 150 feet bsg, respectively. • TPH-g was detected in the soil samples collected from B-4 at 60 feet, 70 feet, 90 feet, 100 feet, 130 feet and 149 feet bsg. Concentrations ranged from 2 .0 mg/kg (134- 100) to 2,500 mg/kg (134-70). • BTEX constituents were detected in the boring B4 samples from 60 feet, 80 feet, 90 feet, 130 feet and 149 feet. Maximum concentrations were detected in sample 134-70 at 4 .7 mg/kg benzene, 32 mg/kg toluene, 7.9 mg/kg ethylbenzene and 45 mg/kg xylenes. • TPH-g was detected in the ground water samples collected from wells MW4Cand MW- 1D at concentrations of 3,800 micrograms per liter (µg/1) and 6,400 µg/1, respectively. • BTEX constituents were detected in the samples from wells MW-1C and MW-1D with maximum concentrations in well MW- 1D at 170 µg/1 benzene, 870 µg/1 toluene, 180 µg/1 ethylbenzene, and 760 µg/1 xylenes. • The fuel oxygenates MTBE andDIPE were detected in well MW- 1D at concentrations of 9. 8 µg/1 and 3 . 6 µg/1, respectively. DIPE was detected in well MW- 1 C at a concentration of 4 .4 1 . The lead scavenger 1 ,2-DCA was detected in both wells at concentrations of 3 .0 1 µ2� g µg/ and 5 .4 µg/1, respectively. On 26 and 27 January 2006, soil boring CPT-5 was advanced off-site, at 540 North California Street utilizing CPT technology to model the geologic and hydrogeologic framework and to assess potential dissolved petroleum migration from the site. Lithologic data was collected from an initial CPT soil boring; adjacent borings were then advanced to collect grab ground water samples from selected depths. Soil boring CPT-5 was advanced to a total depth of 200 feetbsg. Ground water samples were collected from the CPT boring at the following intervals: 59 to 63 feet bsg, 72 to 75 feet bsg, 104 to 108 feet bsg, 117 to 121 feet bsg, and 171 .5 feet and 174 .5 feet bsg. Advanced GeoEnvironmenfal, rne.