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Page 4 September 11,2023 Brusca File No. 260-004 Anderson Barngrover Ranch Soil sampling was performed within each of the borings generally at ten-foot depth intervals and the subsurface conditions were logged by a Professional Geologist from our office; logs of borings are presented as Plates 4 through 6. The borings encountered alluvial deposits primarily comprised of sandy silts extending to depths on the order of 13 feet. Below depths of about 13 feet, the borings mostly encountered sands and silty sands. The borings encountered a prominent sandy gravel layer around a depth of 33 feet and extending to depths on the order of 40 feet. Below the gravel layer,the borings encountered mostly silty sands, sands,and silts extending to the maximum depth of exploration. None of the soils encountered in Borings TH8, TH9, or TH10 exhibited field evidence of petroleum hydrocarbon impact, except that soils at a depth on order of 70 feet in Boring B9 and at a depth of 60 feet in Boring B 10 exited a petroleum hydrocarbon odor. During drilling, soils retrieved from the borings were field screened with a hand-held photoionization detector (PID); the PID readings are presented on the attached boring logs. Soil samples were retrieved from the borings for laboratory testing at ten-foot depth intervals; the designations and depths of the samples selected for analysis are shown on the attached Table I. The soil samples were retrieved in stainless-steel sleeves and sealed with Teflon tape and plastic end caps. The soil samples collected from the borings were labeled, immediately placed on ice, and transported under chain-of-custody documentation to a State-certified laboratory for analysis. As indicated above, groundwater was encountered in Borings TH8, TH9, and TH10 and stabilized in the boreholes at depths ranging from 64 feet to 69 feet. A temporary PVC well was installed in each borehole and a groundwater sample was obtained from each boring via a dedicated disposable bailer and immediately transferred to laboratory-provided sample containers (VOAs). The groundwater samples were labelled, placed on ice, and transported under chain-of-custody documentation to a State-certified laboratory for analysis. No evidence of sheen or free product was observed during the groundwater sampling. Additionally, gauging of the borings with an interface probe did not indicate free product on groundwater in the boreholes. Following the drilling and sampling activities, each boring was backfilled with neat cement grout via tremmie in accord with SJCEHD requirements. Soil cuttings and decontamination water generated during the drilling activities were containerized in 55-gallon drums and stored onsite pending disposal. Soil Gas Probe Installation and Soil Gas Sampling In accordance with the approved Workplan, we installed and sampled a soil gas probe the SG3 location where soil gas sampling was unsuccessfully attempted in May 2023 (the sampling equipment for that location provided by the laboratory in May was faulty). The SG3 location is shown on Plate 3. At the soil gas sampling location,a temporary soil gas sampling probe comprised of Teflon tubing with filter connected to the end was installed to the target depth. The probe hole extended to a depth of 6.0 feet and the filter was emplaced at a depth of 5.5 feet. The portion of the probe immediately surrounding the dedicated soil gas sampling tip (from a depth of 5.0 feet to 6.0 feet)was backfilled with clean sand,and the remainder of each probe hole was sealed to the surface with hydrated bentonite.