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GROUNDWATER MONITORING WELL INSTALLATIONS (2004) In March 2004, groundwater monitoring wells MW-1 through MW-4 were installed at the Site, at the approximate locations shown on Figure 2. Wells were drilled to depths ranging between 45 and 55 feet bgs and were constructed with 2-inch diameter schedule 40 PVC casing with 20 feet screened intervals set at the base of each boring. Well construction details are presented in Table 4. TPHg, benzene and ethylbenzene were detected in soil samples collected from the well borings at maximum concentrations of 57 mg/kg, 0.44 mg/kg and 0.20 mg/kg, respectively (AGE, 2004). Petroleum hydrocarbons were detected in the initial groundwater samples collected from each of the wells, with maximum concentrations of TPHg (82,000 micrograms per liter [ug/1]), benzene and ethylbenzene (1,100 ug/1), and MTBE (11,000 ug/1) detected in the groundwater sample collected from well MW-2 (AGE, 2004). Laboratory analytical results for soil samples and groundwater well samples collected from well drilling and sampling are further summarized in Tables 1 and 3, respectively. REMEDIATION WELL INSTALLATIONS AND REMEDIATION PILOT TESTING (2005) In March 2005, vapor extraction wells VW-1 through VW-4 and extraction well EW-1 were installed at the Site, at the approximate locations shown on Figure 2. Vapor extraction wells VW-1 through VW-4 were drilled to 35 feet bgs and constructed with 2-inch diameter schedule 40 PVC screened between 15 and 35 feet bgs. Extraction well EW-1 was drilled to 55 feet bgs and constructed with 4-inch diameter schedule 40 PVC screened between 35 to 55 feet bgs (AGE, 2006) (Table 4). Laboratory analytical results of soil samples collected during well drilling are presented in Table 1. Following remediation well installations, a vapor extraction pilot test was conducted using well VW-3. The vapor extraction pilot test was conducted at an applied vacuum of 94 inches of water with corresponding flow rates between 30 and 34 standard cubic feet per minute (scfm). Based on vacuum responses measured in wells VW-1, VW-2, VW-4 and MW2, a calculated radius of influence was reported to be approximately 28 feet(AGE, 2006). Subsequent to installation and development of extraction well EW-1, a variable rate pump test was conducted on the well with on-Site monitoring wells MW-1 through MW-4 used as observation wells. Based on the results of the pump test, it was concluded that a hydraulic conductivity values for pumping rates of 0.75 gallons/minute and 1.0 gallons per minute were 0.47 feet per day and 0.53 ft/day, respectively (AGE, 2006). EXPLORATORY BORING INVESTIGATIONS (2008) In February and March 2008, on-Site CPT borings CPT1 through CPT3 and off-Site boring CPT4 were advanced at the approximate locations shown on Figure 2. CPT borings were advanced to depths of 125 feet bgs for collection of soil and groundwater samples. TPHg, benzene and ethylbenzene were detected in soil samples at maximum concentrations of 220 mg/kg, 4.1 mg/kg and 15 mg/kg, respectively (Table 1). Groundwater samples were collected from CPT 1 through CPT3 at depths ranging between 74 and 125 feet bgs, and from CPT-4 FREY Environmental,Inc. 4 Project No. 1095-01