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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 between 39 feet bgs and 109 feet bgs. Total purgeable gasoline range petroleum hydrocarbons (TPPH) were detected in grab groundwater samples collected from CPT9, CPT 10 and CPT 12 locations at concentrations ranging from 800 ug/l (CPT12-105) to 7,000 ug/l (CPT9-70). Petroleum hydrocarbons were not detected in grab groundwater samples collected from the CPT I hydropunch boring location (FREY, 2023). Hydropunch groundwater sample analytical results are further summarized in Table 2. Based on the results of the investigation, FREY concluded that the lateral and vertical extent of dissolved phase petroleum hydrocarbons northeast of CPT12 were not adequately assessed. FREY additionally concluded that the lateral extent of dissolved phase petroleum hydrocarbons were not adequately assessed in the intermediate depth groundwater zone southeast of the Site (FREY, 2024). ADDITIONAL OFF-SITE HYDROPUNCH SAMPLING AND MONITORING WELL INSTALLATIONS (2023) Hydropunch Sampling To assist in selecting locations for two additional groundwater monitoring wells northeast and southeast of the Site, on September 20 and 21, 2023, hydropunch borings HP1 and HP2 were advanced at the approximate locations shown on Figure 3. Groundwater samples were collected at 100 and 120 feet bgs in hydropunch boring HP1, and at 60 and 78 feet bgs (where refusal was met) in hydropunch boring HP2 (FREY, 2024). TPH-GRO were detected at a concentration of 460 ug/l and benzene was detected at a concentration of 14 ug/1 in the groundwater sample collected from boring HP 1 at 100 feet bgs. TPH-GRO were detected at a concentration of 67 ug/l and benzene was detected at a concentration of 0.65 ug/1 in the groundwater sample collected from 120 feet bgs in boring HP I. TPH-GRO were detected at a concentration of 25,000 ug/l, benzene was detected at a concentration of 2,400 ug/l, ethylbenzene was detected at a concentration of 2,100 ug/l, and naphthalene was detected at a concentration of 890 ug/1 in the groundwater sample collected from boring HP2 at 60 feet bgs. TPH-GRO were detected at a concentration of 3,900 ug/l, benzene was detected at a concentration of 440 ug/1 and ethylbenzene was detected at a concentration of 9.1 ug/l in the groundwater sample collected from 78 feet bgs in boring HP2 (FREY, 2024). Hydropunch groundwater sample analytical results are further summarized in Table 2. Monitoring Well Installations Groundwater monitoring wells MW16 and MW17 were installed on September 20 and 21, 2023. Monitoring well MW 16 was constructed with 2-inch diameter schedule 40 PVC with 10 feet of slotted casing extending between the depths of 95 and 105 feet bgs. Monitoring well MW 17 was constructed with 2-inch diameter schedule 40 PVC with 10 feet of slotted casing extending FREY Environmental,Inc. 7 Project No. 1095-01