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technique and groundwater samples collected once the groundwater purge parameters have stabilized. A minimum of one tubing and pump volume will be removed from each well before a sample is collected. Specifically, stabilization will be considered to be achieved when three consecutive readings are within the following limits: turbidity (10% for values greater than 5 Nephelometric Turbidity Units), pH (+/- 0.1 unit), specific conductance (3%), dissolved oxygen (10% for values greater than 0.5 mg/L, if three dissolved oxygen values are less than 0.5 mg/L, consider the values as stabilized), oxidation/reduction potential (+/- 10 millivolts), and temperature (3%). Purging and sampling will be conducted using a Purging and sampling will be conducted using a controlled-flow Grunfos Redi-Flo2 electric submersible pump. Purge water will be temporarily stored on-site in DOT-approved steel 55-gallon drums. The handling and disposal of the purge water will be conducted in accordance with the procedures described for decontamination fluids and well development water and other IDW. The groundwater samples will be contained in 40-ml laboratory-grade VOA vials preserved with hydrochloric acid (HCL). Groundwater samples collected for analysis of TPH-d and TPH-mo will be contained in one-liter amber glass bottles. The samples will be labeled with the project number, sampler's initials, boring number, and the time at which the sample was obtained. Following sample labeling, each sample will be placed into a thermal chest with synthetic ice to limit the volatilization of any constituents present. Groundwater samples will be preserved and transported within cooler chests containing ice and maintained at a temperature of approximately 4 degrees Celsius. Laboratory quality assurance/quality control (QA/QC)will be performed commensurate with US EPA Level II QA/QC procedures. 5.5.2 Proposed Groundwater Sample Analysis The proposed location of the groundwater monitoring wells are no closer than 40 to 50 feet from the Quality Cleaners and it is not likely PCE could have migrated within the upper ten feet of soil (the unsaturated zone) in a manner that these constituents would be present in unsaturated soil. The absence of PCE becomes even less likely at the locations of the other downgradient monitoring wells. Finally, analysis of soil samples from beneath and adjacent to the Quality Cleaners analyzed as part of partners' January 2015 Phase II did not contain detectable concentrations of VOCs. In addition, soil samples are generally not preferred for Site characterization because only those soils located within the primary release area would be representative of constituent distribution. Given the foregoing, Partner proposes that no soil samples frrm the borings advanced to install the groundwater monitoring wells be submitted for chemical analysis except for the purpose of waste profiling for drill cuttings. Groundwater samples collected from the monitoring wells will be submitted for analysis of TPH in accordance with EPA Method 8015 using a laboratory-obtained standard for DP-2000 and for VOCs in accordance with EPA Method 8260. 5.6 Proposed Quarterly Groundwater Monitoring Program The proposed groundwater monitoring wells will be sampled for four consecutive quarters beginning with the initial monitoring event that will occur following the installation of the monitoring wells. Future monitoring events will consist of the collection of groundwater samples and the measurement of water levels. Sample analytical data and maps depicting groundwater gradients and flow directions will be Sampling and Analysis Plan Tracy Corners Shopping Center 3225 North Tracy Boulevard Tracy,California 95376 Partner Project Number SM14-129814 Docket Number HAS-VCA 14/15-108 August 15,2016 Page 19