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. In September 2000, a sensitive receptor survey was conducted for the site The drainage ditch and island drainage channel are the only potential receptors within a 1,000-foot radius of the site Ms Margaret Lagono of San Joaquin County EHD referred the site to the CVRWQCB for oversight by letter to Mr Marty Hartzell of CVRWQCB, dated 05 January 2001 According to Ms Lagono the action was taken because of their determination that the source of the MTBE contamination was the AST system and not the former UST system In an internal memo dated 29 March 2001, the CVRWQCB concurred with the EHD decision and transferred the site to the CVRWQCB Site Cleanup Section for further oversight On 02 April 2001, the CVRWQCB issued a letter stating that no further action is required for the former UST system at the site By letter dated 05 June 2001,Ms Wendy Cohen ofCVRWQCB finalized Monitoring and Reporting Program (MRP)No 5-0I-0835 and approved Additional Ground Water Investigation Work Plan, dated 07 May 2001, prepared by Condor The MRP describes the ground water monitoring and reporting requirements for the site The work plan was prepared to further investigate the lateral and vertical extent of impacted ground water Ms Cohen also agreed with Condor's recommendation to abandon well MW-1, since It is no longer a necessary monitoring point for the MTBE plume associated with the AST system at the site On 27 and 28 December 2001 and on 18 and 21 January 2002,AGE advanced ten soil bonngs at the site to assess the lateral and vertical extent of MTBE-impacted ground water Soil probe borings B 1 through BI 0 were advanced vertically to depths ranging from 20 feet bsg to 50 feet bsg Grab ground water samples were collected from every probe boring, with the exception of B5 A total of four soil samples were submitted for laboratory analysis,the 15-and 20-foot samples from boring B5, also located near the former UST area, and the 15- and 25-foot samples from boring B7 TPH-g was detected in the soil samples collected from boring B7 at concentrations of 2,100 (milligrams per kilogram) mg/kg and 0 80 mg/kg BTEX compounds were detected in the 15-foot soil sample collected from borings B7 at concentrations of 22 mg/kg benzene, 130 mg/kg toluene, 40 mg/kg ethylbenzene and 190 mg/kg total xylenes Toluene was detected in the 25-foot soil sample collected from boring B7 at a concentration of 0 03 mg/kg TPH-g and BTEX compounds were not detected at or above laboratory reporting limits in the soil samples collected from boring B5 No other analytes were not detected at or above laboratory reporting limits in the soil samples TPH-g was detected in the ground water sample collected from borings B 1,B3,B4,B6,B7,B8,B9 and B-10 at concentrations ranging from 110 micrograms per liter(µg/l)to 23,000µg/1 One or more BTEX compounds were detected in the samples collected from borings B3, B4, B6 and B7 at concentrations as high as 84 µg/1 benzene,200 µg/l toluene,34 µg/1 ethylbenzene and 160µg/1 total xylenes(B7-30) MTBE was detected by EPA Method 8260B in the samples collected from borings B 1,B4,B6,B7,B8 and B9 at concentrations ranging from 7 0 µg/1(B7-30)to 20,000 µg/l(139-15) No other analytes were detected at or above laboratory reporting limits in the ground water samples Advanced GeoEnvironmental,Inc