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1 On November 28, 2000, Ramage Environmental published Environmental Site Investigation ' Report documenting the results of a sensitive receptor survey and the drilling of confirmation sod borings ' To confirm the effectiveness of remediation efforts, soil samples were collected every 10 feet to a total depth of 100 feet directly beneath the former USTs The soil sample results indicated that except for 560 milligrams per kilogram (mg/kg) of Total Petroleum Hydrocarbons (TPH)-as- gasoline in soil at a depth of approximately 10 feet below ground surface (bgs), the vadose zone soil was remediated by the SVE system To delineate the vertical extent of impacted groundwater, discrete groundwater samples were ' collected with a cone penetration test (CPT) rig at 75, 90, and 125 feet bgs from soil borings located approximately 20 feet northeast (downgradient) of the former UST's The discrete ' groundwater sample results indicated that the vertical extent of impacted groundwater was mostly delineated Concentrations of MTBE declined significantly with depth and were absent in the 125-foot groundwater-bearing interval Only 1,2-dichloroethane (1,2-DCA) was detected in ' the 125-foot groundwater sample, at a low concentration of 0 5 micrograms per liter (p.gll) According to available records, three property parcels within 2,000-feet of the site had operating water wells These properties included the San Joaquin Catholic Cemetery (site), St Joseph's Hospital, and a residential dwelling at 1821 North Hunter Street The locations of the cemetery ' wells and hospital well are shown on Figure 3 ' On May 2, 2002, Ramage Environmental published Report, Additional Site Investigation, which documented the drilling of CPT borings for discrete groundwater sampling at six additional locations, and the installation of a two-well monitoring well cluster (MW-8A and MW-8B) The ' results of the project indicated that the extent of MTBE was defined and limited to the groundwater table northeast (downgradient) of the former UST Only low concentrations (0 5 to ' 1 2 �tg/l) of 1,2-DCA were detected in the 110 to 125 foot groundwater-bearing interval south and west of the former UST ' Between January 18, 2003 and August 25, 2004, Ramage Environmental supervised the monthly batch extraction of groundwater from MW-5 and MW-7 After seven extraction events, the concentrations of MTBE in MW-5 increased slightly from 92 to 100 µg11, and in MW-7 decreased from 390 to 100 µg11 The results of the groundwater extraction effort are summarized in Ramage Environmental's Groundwater Monitoring and Extraction Report, Third Quarter2004, dated December 17, 2004 s ' 4 1