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M to 47 feet bgs, and with neat cement grout from 47 feet to 0.65 feet bgs, and capped with a "Christy box" or similar traffic cover installed with aggregate cement. See well construction details (Appendix C) for additional information. Soil borings ' in which no wells are to be constructed will be advanced to a depth of 60 feet and will be backfilled with neat cement. After the monitoring wells have equilibrated for a minimum of 48 hours, depth to static water level will be measured with an electric water level measuring tape that is coated with hydrocarbon-sensitive paste to detect and measure the thickness ' of any floating product that might be present, after which the wells will be developed and sampled. Well development typically involves surging the well with a vented surge block, followed by purging the well with an appropriate pump or clean, poly- ethylene bailer until the sediment is removed from the bottom of the well, the water is observed to be relatively non-turbid, and the water temperature, pH, and electrical conductivity ' readings are stabilized. Following purging, and recovery of the total depth of water within the well to 80% of its original ( static ) volume, groundwater in the well will be sampled. Sampling will be done by lowering a clean, disposable, poly- ethylene bailer into the water. Upon removal of the bailer, the water sample will be transferred into two ( 2 ) one-liter amber glass bottles, three ( 3 ) 40-m1 Volatile Organic Analysis (VOA) vials containing HCl preservative, and filtered into two ( 2 ) 500-m1 polyethylene bottles containing HNO3 preservative. After the containers are filled, they will be sealed with teflon- lined screw caps, labeled, and stored under ice in a cooler pending transportation to a State-certified laboratory for analysis for TPH-G and BTEX using EPA Methods 5030/8015-8020 ( 602) , TPH-D using EPA Methods 3510/8015, and Halogenated Volatile Organic Compounds using EPA Method 601 . ' All auger spill will be stored on and covered by polyethylene sheeting pending determination of a disposal protocol appropriate to the degree of contamination of these soils. Waste water from cleaning the sampling equipment and steam-cleaning the augers, and waters purged during development and sampling of the monitoring wells, will be stored in covered DOT drums, also pending development of an appropriate disposal protocol. 1 PROPOSED SCHEDULE OF WORK ' Drilling of the soil borings and installation of the monitoring wells can commence within two weeks of approval of a workplan and issuance of permits by the San Joaquin County Department of Public Health Services. The installation of the soil borings and construction of monitoring wells is expected to take five 6. 1