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EXECUTIVE SUMMARY The objectives of the project scope of work were to survey any possible sensitive receptors in the site vicinity, evaluate the effectiveness of the remediation system, and to monitor the plume of impacted groundwater To achieve these objectives, Ramage Environmental conducted a sensitive receptor survey, supervised the drilling of confirmation soil borings, and monitored and sampled the groundwater monitoring well network According to available records, three property parcels within 2,000-feet of the site have operating water wells These properties include the San Joaquin Catholic Cemetery (site), St Joseph's Hospital, and a residential dwelling at 1821 North Hunter Street The nearest hospital ' to the site is the St Joseph's Hospital approximately 500 feet to the west, and the nearest school is the Commodore Stockton Skills School approximately 1,500 feet southwest of the site There are no significant surface water bodies within the site vicinity ' To confirm the effectiveness of remediation efforts, soil samples were collected every 10 feet to a total depth of 100 feet directly beneath the former USTs The soil sample results indicate that except for 560 mg/kg of TPH-as-gasoline in soil at a depth of approximately 10 feet bgs, the vadose zone was almost completely remediated To delineate the vertical extent of impacted groundwater, discrete groundwater samples were collected at 75, 90, and 125 feet bgs from soil borings located approximately 20 fleet northeast (downgradient) of the former USTs The discrete groundwater sample results indicate that the vertical extent of impacted groundwater is mostly delineated Concentrations of MTBE decline significantly with depth and are not present in the 125-foot groundwater-bearing interval Only 1,2-DCA was detected in the 125-foot groundwater sample, at a concentration of 0 5 µg11 ' In the groundwater well samples, concentrations of gasoline hydrocarbons continued to decline The highest concentration of TPH-as-gasoline was detected in VW-2D at 90 µg11 The highest concentration of MTBE was detected in MW-3 at a 100 µg11 In the downgradient deeper wells(MW-4 and MW-5), MTBE was detected for the first time For the second consecutive quarter, MTBE and 1,2-DCA were detected in downgradient well MW-7 As such, the lateral extent of MTBE in groundwater is no longer defined in the downgradient direction Based on these conclusions, Ramage Environmental recommends the following course of environmental corrective action 1 Continue quarterly groundwater monitoring, sampling and analysis ' 2 Meet with RWQCB staff to determine a strategy to pursue regulatory closure 1