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OFF-SITE CONEPENETROMETER INVESTIGATION (2014) In July 2014, CPT borings CPT5 through CPT8 were advanced at the approximate locations shown on Figure 2. CPT borings were advanced to depths of 85 feet bgs for lithologic profiling, with groundwater samples collected between the intervals of 76 to 80 feet bgs. TPHg and benzene were detected in the groundwater samples collected from CPT-5, CPT-6 and CPT-8 at maximum concentrations of 9,700 ug/1 and 5,600 ug/l, respectively (AGE, 2014). Laboratory analytical results for the groundwater grab samples are further summarized in Table 2. ADDITIONAL OFF-SITE ASSESSMENT AND MONITORING WELL INSTALLATIONS (2015) In May and June 2015, off-Site soil borings B9 and B11, and monitoring wells MW-12 through MW-15 were installed at the approximate locations shown on Figure 3. Soil borings B9 and B11 were drilled to depths of 80 feet bgs, with groundwater samples collected at depths of 40 feet bgs, and between 76 and 80 feet bgs from boring B9. Monitoring wells MW12, MW14 and MW 15 were drilled to depths of 80 feet bgs and completed using 2-inch diameter schedule 40 PVC casing with 5 feet of screened interval set at the base of the boring. Monitoring well MW 13 was drilled to a depth of 50 feet bgs completed using 2-inch diameter schedule 40 PVC casing with 15 feet of screened interval set at the base of the boring (AGE, 2015) (Table 4). With exception to a benzene (4.5 ug/1) detection in the groundwater sample collected from B9 at 80 feet bgs, and toluene (1.1 ug/1) and total xylenes (1.3 ug/1) detected in the groundwater sample collected from boring B11, petroleum hydrocarbons were not detected in the groundwater grab samples collected from borings B9 and B 11 (Table 2). Laboratory analytical results for groundwater samples collected from newly installed wells MW-12 through MW-15 are summarized in Table 3. REMEDIATION SYSTEM INSTALLATION AND OPERATION (2012—2016) The installation of a multi-phase extraction remediation system was completed in December 2012. The MPE system operated between December 17, 2012, and June 27, 2016, recovering an estimated 1,985 lbs. of vapor phase petroleum hydrocarbons and approximately 317 lbs. of dissolved phase petroleum hydrocarbons. Operation of the MPE system was terminated in June 2016 due to low influent TPH concentrations (AGE, 2016). CONEPENETROMETER TESTING AND HYDROPUNCH SAMPLING (2022) To further characterize the nature of the subsurface stratigraphy northeast, east and southeast of the Site, four CPT lithologic borings identified as CPT9 through CPT12 were advanced on November 28 and 29, 2022 at the locations shown on Figure 3. Hydropunch borings were advanced adjacent to each lithologic CPT borings for collection of groundwater samples on November 29, 2022 (CPT9) and December 5, 2022 (CPT 10 through CPT 12). CPT and hydropunch borings were advanced to approximate depths ranging between 66 feet bgs (CPT 10) and 110 feet bgs (CPT9). Based on the CPT lithologic interpretations of the CPT borings, grab samples of groundwater were collected from the companion hydropunch borings at multiple depths intervals ranging FREY Environmental,Inc. 6 Project No. 1095-01