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I Aquifer Pump Test Report of Findings Frontier Transportation, Inc. November 8, 2006 Page 2 Groundwater samples were collected from monitoring wells MW- 1 , MW-2, and MW-3 on 1 August 30, 1996 and April 21 , 1997 by Twinning. In January of 1998, Blakely Environmental Investigations, Inc. (BEII) advanced four (4) groundwater monitoring wells (MW-4 through MW-7) to assess the extent of subsurface contamination beneath the site. Soil samples were collected every five feet. Laboratory analysis of soil samples identified no detectable concentrations of TPH-g, BTEX, or MTBE. In January 2000, BEII advanced two borings 03-5 and B-6), installed four additional groundwater monitoring wells (MW- 8 through MW- 11 ), and collected nine soil vapor samples for a soil vapor survey as part of an additional site assessment. Soil sample analysis identified no detectable concentrations of petroleum hydrocarbons with the exception ofboring B-6. Maximum contaminant levels in B-6 were identified 100 mg/kg as TPH-g, 2,343 pg/kg as BTEX, and 10,600 µg/kg as MTBE at I O' bgs. Maximum soil vapor concentrations were identified at sample point V5 at 4' bgs. Groundwater samples were subsequently collected from all monitoring wells. In May 2002, BEII installed two additional groundwater monitoring wells (MW. 12and MW- 13) screened from 30' bgs to 40' bgs. Soil sample results identified maximum TPH-g, BTEX, and MTBE concentrations of 700 mg/kg, 115,000 µg/kg, and 25 ,000 µg/kg in soil collected fromMW-13 at 10' bgs. Soil concentrations attenuate by 99% at 15 ' bgs. No detectable TPH-g, BTEX, and MTBE were identified in MW- 12 . Also, monitoring well MW-3 was abandoned prior to excavation 1 and removal of 325 tons of impacted soil and replaced by MW-3R. In June 2003 , BEII installed an additional groundwater monitoring well (MW- 14) screened from 30 ' bgs to 40' bgs. Soil sample results identified a maximum MTBE concentration of 1 ,020 µg/kg at 10 ' bgs using EPA Method 8260B. No detectable concentrations ofTPH-g or BTEX were identified in the soil collected from MW44. See Figure 2 for well locations. In January 2004, BEII installed four additional groundwater monitoring wells. Deep monitoring wells MW- 15, MW46 and MW- 18 were advanced to 40 ' bgs and screened from 30' bgs to 40 ' bgs. Shallow monitoring well MW- 17 was advanced to 20 ' bgs and screened from 5 ' bgs to 20' bgs. Soil sample results identified a maximum MTBE concentration of 1 ,310 pg/kg at 10 ' bgs in MW45 using EPA Method 8260B . No other oxygenates or lead scavengers were detected. The i