ARCHIVED REPORTS_LIMITED PHASE 2 SOIL REPORT

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Q Limited Phase 11 Subsurface Investigation Report Property Lease Port of Stockton Stockton,California a ntea g ro u p Antea Group Project No. UPR8298B Laboratory QA/QC Performed: Yes(memo provided by CRA) Laboratory method blanks and quality control Yes, data qualifiers were noted however none appear to affect the samples analyzed: validity of the data reported(see lab report) Are the data valid for their intended purpose? Yes Based on a review of the laboratory's analytical reports, including the laboratory QA/QC procedures and those implemented by CRA,we conclude that the laboratory data obtained during this soil sampling event are acceptable and usable for their intended purpose. 5.0 CONCLUSIONS AND RECOMMENDATIONS On April 15 and 16, 2014, Antea Group oversaw Cascade complete a limited, shallow soil sampling event at the subject site on Rough and Ready Island in the Port of Stockton, in Stockton, California. Cascade advanced a total of 28 soil borings by hand auger and direct-push rig at the locations depicted on Figure 2. Antea Group field-screened soil samples and collected a minimum one sample from each boring for submittal to a state- certified laboratory for analysis by one or more of the contaminants of concern listed in Section 3.3. • Field screening of shallow soils showed no elevated PID readings at any of the locations. Laboratory data indicated that certain soil contaminants, including VOCs and petroleum constituents, are not present at concentrations greater than RWQCB Direct Exposure Screening Levels. • Laboratory analytical results indicate that VOCs, PCBs, and pesticides do not appear to be a significant or widespread environmental concern in the areas of planned soil disturbance for welding facility construction. • The testing results reported only one metal (arsenic) at a concentration exceeding the RWQCB Direct Exposure Soil Screening Level of 10 mg/kg. Other analyzed metals in the remaining soil samples are reported at concentrations less than published background concentrations in California soils, with the exception of a few locations where concentrations were slightly above background, but well below SSLs for the trench worker exposure scenario. • Antea Group also reviewed the metal data to determine site-specific background trends and to determine anomalously high concentrations relative to the rest of background metals concentrations in shallow soils at the site. No trends were apparent in the analyzed soils. Based on the results of this limited subsurface investigation, Antea Group concludes that soils in the areas of planned soil disturbance are not a significant risk to construction contractors performing work on the property. While metals, polychlorinated biphenyls (PCBs), pesticides, and VOCs are present in site soils, they are not at concentrations that warrant additional investigation and/or special consideration. In comparing soil detections with SSLs and typical background metal concentrations, this limited soil investigation did not identify areas of concern; concentrations of metals, pesticides, and PCBs in shallow soils are minimal with regard to construction worker safety. Based on analytical data obtained during this investigation, Antea Group 7 www.anteagroup.com