ARCHIVED REPORTS_SITE INVESTIGATION AND WELL DESTRUCTION PERMIT

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Shell Site Investigation Report Section 4.0 Investigation Findings 4.1 Soil The soil chemical analytical data are summarized in Tables 2. Figure 4 presents soil chemical concentration data for each soil boring. The laboratory analytical report is presented in Appendix B. CRA's independent data validation of the laboratory analytical results is provided as Appendix C. TPHc and BTEX were not detected in any samples collected from the borings lateral to the pipeline alignment at MW-15 (B-117 and B-119),which provides delineation of crude oil impact at MW-15 lateral to the pipeline alignment. Soil boring B-118 was placed along the pipeline alignment and northwest of MW-15. TPHC and BTEX were not detected in the 5-foot sample from boring B-119. TPHc was detected in the samples collected from 10 to 35 fbg at concentrations ranging from 7,000(20 fbg) to 37,000 mg/kg(15 fbg). Benzene was detected at concentrations of 6.4 and 8.3 mg/kg in the soil samples collected from B-118 at 35 and 40 fbg, respectively. Ethylbenzene and xylenes were detected in the sail samples collected from B-118 at 35 fbg at concentrations 20 and 6.1 mg/kg respectively. BTEX was not detected in any other soil samples. BTEX reporting limits for select soil samples were elevated due to matrix interference from heavier crude oil hydrocarbons present in the sample. Soil boring B-118 was placed as close as possible to the property line in an effort to delineate crude oil impact northwest of MW-15. Based on the soil sample analytical results from B-118, crude oil impacts are not delineated to the northwest.Access to the property immediately north of this soil boring was denied by the property owner, as noted in the work plan, and limited northwest delineation. TPHc and BTEX were non-detect in all soil samples collected from boring MW-16 except for at detection of TPHc at 29 mg/kg at 10 fbg. The results provide lateral delineation to the east for crude oil impacts in soil at boring B-109. As noted in the work plan,delineation to the southeast could not be conducted due to presence of Hansen Road and because access to the property southeast of B-109 was denied. 4.2 Groundwater The groundwater chemical analytical data are summarized in Tables 3 along with water elevation data. The laboratory analytical report is presented in Appendix B. CRA's independent data validation of the laboratory analytical results is provided as Appendix C. CRA prepared a groundwater chemical concentration map with TPHc and benzene analytical results(Figure 3). On June 26, 2014,the depth to groundwater in MW-16 was measured at 36.75 fbg. The corresponding groundwater elevation is 86.19 feet above mean sea level. TPHc and BTEX were not detected in the 060223(35) AF'A CONESTOGA-ROVERS 'V &ASSOCIATES September 2014 5