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AUG 17 '99 15: 11 FR LFR ROSEVILLE 916 79G 0366 TO 9-12094683433 R.06/oe LFR Levine-Fricke • • DRAFT Each SVE well and the groundwater monitoring well will be constructed using 2-inch inside-diameter polyvinyl chloride (PVC) casing. The perforated interval of each well will consist of 0.02-inch factory-cut slots. After installing the casings in the hollow-stem auger, number 3 size sand pack will be placed in the annular space from the bottom of the boring to approximately 1 foot above the top of the slots. Bentonite pellets will then be placed above the sand pack and hydrated to prevent the entrance of grout into the sand pack. A cement bentonite grout will be placed from the top of the bentonite pellets to the ground surface. A traffic rated well vault will then be cemented in place at each SVE well to allow for future piping to the well heads. A tamper resistant steel stovepipe will be installed at the monitoring well location extending approximately two feet above grade. After completion, the monitoring well will be developed using a surge block and a bailer until the turbidity of the water appears relatively clear. Soil cuttings generated during drilling activities will be temporarily stored on-site in DOT approved 55-gallon drums pending waste characterization. Decontamination and well development water generated during drill activities will be placed in the GWET system for treatment. Task 3:Testing of the Soil Vapor Extraction Well Network Testing will be conducted of the newly installed SVE system to help select the size and type of soil-vapor treatment equipment. Testing will include applying a vacuum to each SVE well through a common manifold and measuring the vacuum with respect to time at each well head_ The pressure (vacuum) and the extracted vapor flow rate will be recorded for subsequent interpretation. One soil-vapor sample will be collected from the manifold area and each well head at startup, after the pressure in soil in the vicinity of the wells has reached equilibrium, and at the end of the test. The vapor samples will be collected into one-liter summa canister pending chemical analyses. These samples will be analyzed for fixed gases using ASTM D 1946 and TPHg, BTEX, and MtBE using EPA Method TO-3. Analyses of the soil-vapor samples will be performed by Air Toxics of Folsom, California, a state-certified laboratory. KMEP will obtain authorization from the SJCAPCD prior to conducting SVE pilot and inform the SJCAPCD of pollution control measures implemented during testing activities. Task 4: Surface-Water Sample Collection Surface-water monitoring data from stations S-1 and S-2 on Trapper Slough (Figure 2) have occasionally indicated the presence of very low concentrations of BTEX compounds (highest concentration of 1.3 parts per billion(ppbl xylenes, August 1996) and MtBE (highest concentration of 2.6 ppb, March 1997). As requested by the 12WQCB, surface-water samples from Trapper Slough will be collected at and in the vicinity of the site to evaluate whether these detections of BTEX compounds and MtBE page 12 holc.ger.wp:EBF