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LFR Levine-Fricke collected from other wells at the Site, it is anticipated that the total depth of the boring will be approximately 225 feet bgs. 3.5.2 Production Well Construction and Development After the boring has been advanced to the desired depth, the groundwater monitoring well will be constructed using flush-threaded, 6-inch-diameter, schedule 80, PVC casing. The well screen will be 0.020-inch slotted PVC casing. The length of the well screen will be based on the thickness of the water-yielding sediment encountered. Based on data collected from the four existing groundwater monitoring wells, it is anticipated that the screened interval will be approximately 50 to 75 feet long. Blank PVC casing will be installed from the top of the screened interval to the ground surface. After the well casing has been placed inside the augers, the well annulus materials (sand, bentonite, and grout) will be added. The well annulus opposite the screened interval will be backfilled with clean Number 2/12 Monterey sand to a height of approximately 2 feet above the top of the well screen. A minimum of 3 feet of bentonite chips will be placed above the sand pack to isolate the screened interval from material above and prevent the entrance of grout into the sand pack. If needed, the bentonite chips will be hydrated. After the bentonite seal has hydrated, a clean cement- bentonite grout mix will then be placed in the annular space above the bentonite seal to the ground surface to seal the remainder of the borehole from the possible infiltration of surface water. The SJCEHD will be notified before the well is sealed so that a field inspector may witness this activity. After the well is completed, the top of casing will be surveyed to the nearest 0.01 foot and tied into the elevations of the existing wells by a licensed surveyor. The well will be completed with an above-grade casing with a 4- by-4-foot concrete pad. i The well will be installed outside the burn pile areas in an area undisturbed by the fire. Soil cuttings and drilling fluid generated during well installation activities will be distributed evenly on the surface of the Site in a designated area. The well will be developed a minimum of 24 hours after installation by bailing, surging, and/or pumping to remove sediment left in the well during construction and to enhance the hydraulic communication between the well and surrounding sediments. Observations of pH, temperature, specific conductance, quantity, and clarity of water withdrawn will be recorded after each well volume has been purged during development. The well will be developed until approximately 3 to 10 well casing volumes are removed or until relatively sediment-free water is produced. At the completion of well development, a groundwater sample will be collected for laboratory analysis for the constituents listed in Table 1. Well development purge water will be transferred into a water truck for use as dust control at the Site. Page 6 Traty-gtrly-s=p-rpt-wrkpin(fiml):JEE