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LFR Levine-Fricke 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 wells are 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 l wells by a licensed surveyor. The well will be completed with an above-grade, "stovepipe" type well box with a locking cover to protect the integrity of the well. The well will be installed outside the gravel pit in the northwestern boundary of the Site. Soil cuttings generated during well installation activities will be spread near the well location. 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. I ) Observations of pH, temperature, specific conductance, quantity, and clarity of water withdrawn will be recorded after each well volume has been purged during development.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 I volumes are removed or until relatively sediment-free water is produced. At the J 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 1 transferred into a water truck for use as dust control at the Site. 3.5 Production Well Construction and Development To provide water for dust control during remediation activities, one groundwater production well (PW-1) will be installed. The proposed well location is shown on Figure 2. The production well will be installed and developed in accordance with CCR, Title 27 (SWRCB 1987) (i.e. the monitoring well will be cased and constructed to prevent infiltration of surface water into the well boring, the sampling interval will be appropriately screened and filter packed to enable representative groundwater samples, the annular space above and below the screen interval will be appropriately sealed, and the well will be adequately developed) and the California Well Standards (DWR 1990). The well will be installed using a mud rotary rig. 3.5.1 Soil Boring Advancement Soil lithology will be recorded in a lithologic log by a field geologist using the Unified Soil Classification System by communication with the driller and by viewing the mud cuttings that cycle up to the mud trailer. The lithologic log will be prepared under the direct supervision of a California Registered Geologist who has expertise in stratigraphic well logging. The total depth of the boring will be determined in the field, based on the lithology encountered. Based on lithologic and groundwater elevation data ' l .i Tracy-gvly-s=p-rpo-wrkpin(finap3EE Page 5 7