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Mr. James L.L. Barton • Former Countryside Market <br /> October 19, 2011 Stockton, California <br /> Page 4 of 6 <br /> for lithologic description and for possible chemical analysis. Soil samples will be visually <br /> classified in accordance with the Unified Soil Classification System (USCS) and screened for <br /> volatile organic vapors using a hand-held photoionization detector (PID). Select soil samples (a <br /> minimum two soil samples will be collected at each boring location) will be submitted to a <br /> California-certified laboratory under Chain of Custody protocol and analyzed for TPHg, BTEX <br /> compounds, and 7 fuel oxygenate compounds using USEPA Method 8260B and lead by <br /> USEPA Method 6010B. Soil descriptions, PID readings, and other pertinent observations will <br /> be provided on soil boring\well construction logs. Drilling, soil sampling, USCS descriptions, <br /> and well installation will be completed by an experienced SGI field scientist, working under the <br /> direct supervision of a California Professional Geologist. <br /> All sampling equipment will be cleaned in an aqueous solution of a non-phosphate cleanser, <br /> rinsed with tap water, and rinsed a second time with deionized water to prevent <br /> cross-contamination between sample intervals. Soil cuttings generated during drilling will be <br /> placed in Department of Transportation (DOT)- approved 55-gallon steel drums or a roll-off bin, <br /> and auger decontamination water will be placed in drums on-site pending receipt of the <br /> analytical results. All waste will be properly disposed in accordance with the applicable Federal, <br /> State, and local regulations. <br /> WELL COMPLETION <br /> Groundwater monitoring wells will consist of 2-inch diameter Schedule 40 poly vinyl chloride <br /> (PVC) blank and screened (0.020-inch slot) casing. The screen interval for the groundwater <br /> monitoring wells is expected to extend from approximately 80 to 100 feet bgs. <br /> The filter pack surrounding the screened portion of the well casing will consist of #3 Monterey <br /> sand poured through the auger into the annular space between the well casing and screen and <br /> the wellbore wall. The filter pack surrounding the screened casing in the monitoring well will <br /> extend from the total borehole depth to approximately two feet above the top of screen. <br /> Preliminary well development will be conducted during the emplacement of the filter pack to <br /> compact the filter pack material and to remove fines from the water column within the well <br /> casing. The annular seal above the screened interval will consist of a minimum of two feet of <br /> bentonite chips poured through the auger (and then hydrated), followed by grout installed via <br /> tremmie-pipe to approximately one foot bgs. Surface completion will consist of a flush-mounted, <br /> traffic-rated well box set in concrete to grade at each well location. <br /> WELL DEVELOPMENT <br /> A minimum of 72 hours following installation, each well will be developed to produce <br /> representative water quality samples. Well development will consist of surging and bailing <br /> techniques and will remove at least 10 well casing volumes of water. Well development will <br /> continue until groundwater is reasonably free of sediment to ensure high quality groundwater <br /> samples that are representative of aquifer conditions. Standard water quality parameters will be <br />