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Brusca File No. 137-002 Page 3 December 30, 2022 Murphy Parkway Property Soil Gas Monitoring SOIL GAS LABORATORY TESTING The soil gas samples collected from soil gas monitoring wells SGMW1 and SGMW2 were transported to a State-certified laboratory for analysis. Both soil gas samples were analyzed for methane, oxygen, carbon dioxide, and nitrogen by ASTM Method D1946. The samples also were analyzed for VOCs by EPA Test Method TO-15. The analytical laboratory results are summarized on the attached Table I, along with data from past monitoring. The laboratory reports, internal laboratory QA/QC data, and chain-of-custody documentation also are attached. RESULTS AND DISCUSSION As shown on Table I, the December 2022 soil gas samples collected from SGMW1 and SGMW2 did not contain methane at a concentration above the laboratory reporting limits of 0.00020% and 0.00021%, respectively; methane concern at the site is not indicated by the December 2022 data. Further, as shown on Table I the soil gas samples collected from monitoring wells SGMW1 and SGMW2 in December 2022 did not contain any of the tested VOCs at concentrations above the laboratory reporting limits, except for 2-propanol (isopropyl alcohol) at very low concentrations (20 micrograms per cubic meter [ug/m3] and 13 ug/m3, respectively). As shown on Table I, the detected concentrations of 2-propanol are well below the applicable published screening level (USEPA Regional Screening Level), and thus are not considered a concern. SUMMARY AND CLOSING As described herein, our firm conducted monitoring/sampling of the two soil gas monitoring wells (SGMW1 and SGMW2) at the subject property in December 2022. The purpose of the soil gas monitoring program is to evaluate whether soil gas contaminants, including methane and VOCs, exist at the westerly margin of the property as a result of uncharacterized subsurface wastes that reportedly exist offsite to the west of the subject property. Data from the December 2022 monitoring event do not indicate concentrations of methane or VOCs in soil gas at the monitoring well locations that are considered a concern. As indicated earlier in this report, the required soil gas monitoring program for the subject property is for a five-year period that ended with the fourth quarter 2022 monitoring described herein. None of the soil gas monitoring results from the site over the five-year period identified soil gas conditions of concern. It is our understanding that further soil gas monitoring at the subject property is not required, and no further monitoring is planned at this time.