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In conjunction with advancement of the CPT borings, off-Site direct-push soil borings B-5 through B-8 were advanced at the approximate locations shown on Figure 2. Borings B-5 through B-8 were advanced to depths between 30 and 40 feet bgs. Soil samples were only collected from borings B-5 and B-7. Groundwater samples were collected from each boring. Low concentrations of TPHg and BTEX were detected in soil samples collected from boring 13- 5. TPHg and BTEX were not detected in soil samples collected from boring B-7 (Table 1). TPHg and MTBE were detected in the groundwater sample collected from boring B-5 at a depth of 40 feet bgs at concentrations of 4,500 ug/1 and 4,400 ug/l, respectively. MTBE was also detected in the groundwater sample collected from boring B-6 at a depth of 40 feet bgs at a concentration of 22 ug/l. Petroleum hydrocarbons were not detected in the groundwater grab samples collected from borings B-7 and B-8 (AGE, 2008) (Table 2). MULTI-PHASE EXTRACTION PILOT TESTING(2009) In November 2009, a 68-hour multi-phase extraction (MPE) feasibility test was conducted to assess this remediation method. The MPE test was conducted using a portable remediation system equipped with a 25-horsepower liquid ring pump. MPE was performed simultaneously using wells EW 1 and MW2. Over the duration of the MPE test, groundwater was extracted at an average rate of 1.5 gallons per minute and soil vapors were extracted at an approximate flow rate of 50 scfm. An estimated radius of influence was calculated to be approximately 29 feet. An estimated 88.7 pounds of petroleum hydrocarbons were recovered over the duration of the MPE test(AGE, 2010a). ADDITIONAL GROUNDWATER MONITORING AND REMEDIATION WELL INSTALLATIONS (2010) In June 2010, off-Site groundwater monitoring well MW-5 and on-Site groundwater monitoring wells MW-6 through MW-10 were installed at the approximate locations shown on Figure 2. Wells MW-6 and MW-8 were drilled to depths of 40 feet bgs and completed using 2-inch diameter schedule 40 PVC casing with 20 feet of screened interval set at the base of each boring. Wells MW-5, MW-7 and MW-10 were drilled to depths of 80 feet bgs completed using 2-inch diameter schedule 40 PVC casing with 5 feet of screened interval set at the base of each boring. Well MW-9 was drilled to a depth of 105 feet bgs and completed using 2-inch diameter schedule 40 PVC casing with 10 feet of screened interval set at the base of the boring (Table 4). The highest concentrations of TPHg (11,000 mg/kg), benzene (6.2 mg/kg) and ethylbenzene (13 mg/kg) were detected in soil samples collected from well boring MW-9 at a depth of 50 feet bgs. Petroleum hydrocarbons were not detected in soil samples collected from well boring MW-6 (Table 1). Laboratory analyses were not performed on soil samples collected from well borings MW-7 and MW-8 (AGE, 2010b). Laboratory analytical results for groundwater samples collected from the newly installed monitoring wells are summarized in Table 3. In August 2010, extraction wells EW-2 and EW-3 were installed at the approximate locations shown in Figure 2. Wells EW-2 and EW-3 were drilled to 40 and 45 feet bgs, respectively, and constructed with 4-inch diameter schedule 40 PVC with 25 feet screened interval in well EW-2 and 20 feet screened interval in well EW-3 set at the base of each boring (AGE,2010b) (Table 4). FREY Environmental,Inc. 5 Project No. 1095-01