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SOIL SAMPLING ACTIVITIES AND REQUESTED LABORATORY ANALYSES On June 17, 2022, Kleinfelder staff met at the Site with Inspector Presto and Jones Covey's foreman, Mr. Joseph Malcolm, to perform soil sampling at the locations of six fuel dispensers and associated removed fuel system piping that had been removed prior to the tie of the sampling. As directed by Inspector Pesto, Kleinfelder collected soil samples beneath the pea gravel fill material at a depth approximately 2 feet into the "native" soil (equating to approximately 6 feet to 7 feet bgs) at the former fuel dispenser locations and at intervals of approximately 20 linear feet in the piping trenches. As the pea gravel and soils were excavated, they were screened for the potential presence of volatile organic vapors using a calibrated photo-ionization detector(PID). No volatile organic vapors were detected by the PID at concentrations at or above the instrument's detection limit. The excavated material was then temporarily stockpiled on Site. In total, 13 soil samples were collected during the June 17, 2022 sampling event, including six dispenser location soil samples (designated D-1 through D-6), five piping trench soil samples (designated P-1 through P-5), and two excavated material stockpile samples (designated SP-1 and SP-2). Figure 2 shows the approximate locations where each sample was collected. The soil samples were collected from the bucket of the contractor's excavator and transferred into laboratory-provided glass jars. The stockpile material samples were also placed in laboratory provided glass jars. Field preservation of the samples for laboratory analysis of VOCs was performed pursuant to US EPA Method 5035. Photographs of the Site and selected sampling locations are presented on Figures 3 through 7. A second sampling event occurred on June 30, 2022, when Kleinfelder returned to the Site following the removal of additional fuel system piping. Two soil samples(designated P-6 and P-7) were collected from the newly-excavated piping trench using the same methodology described above. The approximate locations from which the samples were collected are included on Figure 2. As with the first sampling event, no total volatile organic vapors were detected at a concentration at or above the PID's detection limit in the excavated pea gravel and soil. The soil samples collected during each of the two sampling events were submitted, accompanied by chain of custody, to Kleinfelder's laboratory subcontractor, Pace Analytical® Laboratory Sciences (Pace Analytical), located in Bakersfield, California, for analysis. Pursuant to San Joaquin County's requirements, the samples were analyzed for gasoline-range total petroleum hydrocarbons (as total purgeable petroleum hydrocarbons) and VOCs including fuel oxygenates using US EPA Method 8260B and for total lead using US EPA Method 6010B. The soil samples were analyzed using a rush 24-hour results-reporting turn-around-time. SOIL SAMPLING ANALYTICAL RESULTS The analytical results are summarized in attached Table 1, and copies of Pace Analytical's laboratory reports are provided in the last attachment section that follows the table attachment. As the table and laboratory reports indicate, TPH-g as total purgeable petroleum hydrocarbons and VOCs were not detected in the samples at concentrations at or above their respective PQLs, which varied by sample and analyte. Total lead was present in the soil samples collected on June 17, 2022 at concentrations ranging from 4.3 milligrams per kilogram (mg/kg) to 7.3 mg/kg, and present in the two June 30, 2022 samples at concentrations of 7.6 mg/kg and 8.2 mg/kg, although the laboratory flagged the latter two samples' total lead results with a "J" laboratory qualifier, indicating the results are estimated values, and an "A10" qualifier, indicating detection and quantitation limits for lead were raised due to matrix interference. Kleinfelder compared the total lead analytical results for the June 17 and 30, 2022 samples to the current(July 2019) Tier 1 20224378.001A/LH22R143097 Page 2 of 4 July 25, 2022 Copyright 2022 Kleinfelder KLEINFELDER 24411 Ridge Route Dr., Suite 225, Laguna Hills, CA 92618 p 1949.727.4466 f 1949.727.9242