ARCHIVED REPORTS_SOIL AND GROUNDWATER INVESTIGATION WORK PLAN

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' Soil and Groundwater Investigation Work Plan Vernalis Offsite April 2007 ' Soil Sample Analytical Procedures A chain-of-custody document designating the soil samples to be analyzed and other information will ' accompany the samples to the laboratory. Soil samples will be analyzed for the COCs,using the methods and sampling containers listed in Table 3. Collection of Grab Groundwater Samples tIf groundwater is encountered,a grab groundwater sample will be collected,unless SPH in soil or sheen on groundwater are observed. If SPH or sheen are observed, a groundwater sample will typically be collected from other,"step-out"borings in adjacent areas. However, if hydrocarbon-affected soil is ' separated from the groundwater-bearing zone by an interval of unaffected soil by more than 10 feet,then a groundwater sample should be collected for laboratory analysis. Grab groundwater samples will be collected by placing a clean,pre-packed well screen through the rods ' of the GeoProbe®Dual Tube sampling system, and extracting the groundwater into containers using a peristaltic pump. After pumping begins,the pump flow rate will be optimally adjusted to match the yield of the groundwater-bearing zone. The tubing end of the pump will be placed at the midpoint of the ' groundwater column in the boring in order to minimize the entrainment of sediment in the sample,the presence of which could artificially,upwardly bias concentrations of the COCs. ' Groundwater Sample Analytical Procedures A chain-of-custody document designating the groundwater samples to be analyzed and other information will accompany the samples to the laboratory. Groundwater samples will be analyzed for the COCs,using ' the methods and sampling containers listed in Table 3. The samples will be decanted into the sample bottles in the following order: (1)BTEX, (2)TPHd, (3)PAHs,and(4)General Minerals. Additionally, samples will be collected from borings SB-28 and SB-32 and analyzed for the General ' Minerals listed in Table 3, in order to evaluate the suitability of the uppermost groundwater for drinking- water use. The analytical results may be evaluated in combination with available data from nearby Historical Pipeline Portfolio(HPP)sites such as the TAOC Ohm Pump Station. ' Collection of Fuel-Fingerprint Samples In order to assess whether media were affected by SJV crude oil or another petroleum product, at least one fuel-fingerprint sample may be collected and submitted to Chevron Energy Technology Company for ' fingerprinting. If no petroleum-affected soil or groundwater is found, then no fuel-fingerprint sample will be collected. Fuel-fingerprint samples will be analyzed using gas chromatography/mass spectrometry. Soil Boring Abandonment Soil borings will be sealed and abandoned in accordance with SJCEHD and SCDER requirements. Following abandonment, each soil boring will be located using a global positioning system unit. Boring ' locations will be surveyed for x and y coordinates with reference to the North American Datum 83 State Plane Zone 3 U.S. These data will be used to place the borings on a geo-referenced base map. 3.4 QUALITY ASSURANCE/QUALITY CONTROL AND DATA USABILITY rField sampling will be conducted in accordance with SAIC's Quality Assurance and Quality Control Sample Collection, Handling, and Analysis procedures(SAIC,2006b). In accordance with those procedures,quality assurance samples will be collected and analyzed according to the specifications listed in Table 4. Requests for trip blank, equipment rinsate blank, duplicate, and matrix spike/matrix spike duplicate analyses will be specified on the chain-of-custody form. ' After receipt of all final laboratory reports, SAIC will perform a data usability evaluation to determine whether the data can be used for their intended purposes. The evaluation will be summarized in the Data Usability Summary of the next SGIR. ' From Science to Solutions