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I , r plating facility area to obtain background concentrations of metals in soil. The locations of the borings (SS -1 through SS -8 and BG -1) are presented in Figure 2. On October 9, 2008, twenty four soil samples were collected at boring locations within the facility and two at the background location outside of the facility. The borings were completed and samples collected using a limited access track mounted Geoprobe® sampling system. A Copy of the boring permit obtained to complete soil sampling from borings and the sampling procedures for selection of soil samples are presented in Attachment 4. A summary of soil samples collected at the site, including those from soil borings, are presented in Table 2. Upon completion of the borings, the boreholes were sealed under the oversight of the San Joaquin Environmental Health Department (inspector Harlin Knoll). Boring logs are presented as Attachment 5. Soil Sample Analytical Results The results of the verification samples collected in the soil borings are presented in Tables 3 through 6. Soil samples collected from borings were analyzed for CAM 17 metals, volatile organic compounds (VOCs), semi -volatile organic compounds (SVOCs), and pH. VOCs and SVOCs were not detected in soil samples collected from borings. The pH results ranged from 5.34 to 9.64, with only one sample exceeding 9. Metals concentrations were generally similar when compared to each other (no sample being orders of magnitude higher than background conditions). A few samples collected at two locations contained elevated concentrations of cadmium and nickel that exceeded screening levels. Concentrations of concern were detected at boring locations SS -3 (elevated cadmium levels) and SS -4 (elevated nickel levels). Table 7 presents the samples with concentrations of Cadmium and Nickel exceeding California Human Health Screening Levels (CHHSLs) or Preliminary Remediation Goals (PRGs). A summary of the CHHSLs and PRGs used for metals are presented in Table 8. A short soil sampling summary report, dated November 4, 2008, was submitted to the DTSC. The report presented the soil analytical results, proposed areas to be excavated, and described the methods to be used during excavation and sampling. The proposed work was approved by the DTSC in an email dated November 17, 2008. Excavation of Contaminated Soil The first excavation was located at soil sample location SS -3 and was performed to remove elevated concentrations of cadmium found in soil. A 4 foot by 4 foot area of concrete was removed and soil excavated to a depth of 3 feet to remove concentrations of cadmium exceeding California Human health Screening Levels (CHHSLs). Verification samples were collected from the excavation and results indicated that no further excavation would be needed. The excavation location is shown in Figure 2 and the verification sample locations, depths, and results are presented in Figure 3. 0837 CRpt 5 CRI