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Frontier Transportation, Inc. Well Installation Work Plan July 30, 2008 Page 2 wells MW- 1 , MW-2, and MW-3 on August 30, 1996 and April 21 , 1997 by Twinning. Results are presented in Table 1 . 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 (See Figure 2, Site Layout Map) . Soil samples were collected every five feet. Laboratory analysis of soil samples identified no detectable concentrations of TPH-g, BTEX, or MTBE. Groundwater samples were subsequently collected. See Table 1 . In January 2000, BEII advanced two borings (B-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 (See Figure 2, Site Layout Map for well locations) . Soil sample analysis identified no detectable concentrations of petroleum hydrocarbons with the exception of boring B-6. Maximum contaminant levels in B-6 were identified 100 mg/kg as TPH-g, 2, 343 µg/kg as BTEX, and 10,600 µg/kg as MTBE at 10 ' bgs. Maximum soil vapor concentrations were identified at sample point V5 at 4 ' bgs. Groundwater samples were subsequently collected from all monitoring wells. Groundwater results are tabulated in Table 1 . In May 2002, BEII installed two deeper groundwater monitoring wells (MW- 12 and 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 from MW- 13 at 10 ' bgs. Soil concentrations attenuate by 99% at 15 ' bgs. No detectable TPH-g, BTEX, and MTBE were identified in MW42 . Also, monitoring well MW-3 was abandoned prior to excavation 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 o ,020 µ at 10 ' bgs using EPA Method 8260B . No detectable TPH-g and BTEX were identified in MW-Tz �} y� 1 y�.�i Q, old- 0 1 i a lc( -+`. n a , In January 2004, BEII installed four additional groundwater monitoring wells. Deep monitoring wells MW- 15 , MW- 16 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 '