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Well construction materials would consist of 2-inch diameter Schedule 40 PVC casing with flush • threaded joints The length of the slotted interval would be 20 feet to facilitate the apparent drop in groundwater elevation over the past several years The length of the slotted interval would be adjusted If a competent confining layer is encountered The anticipated depth of the slotted interval would be from 65 to 85 feet Prior to installation in the bore, the PVC casing and slotted pipe would be washed with a high-pressure hot water cleaner The annular space around the slotted interval would be backfilled with washed, kiln-dried, graded sand The sand would be placed through the hollow stem auger to a level two feet above the slotted interval A three-foot layer of 1/4-Inch bentonite pellets would be placed above the sand pack and hydrated with potable water Neat cement with up to 4% bentonite would be placed above the bentonite pellet seal by the tremae method Tension would be maintained on the casing during backfilling A water-tight traffic rated vault would be Installed around the surface of the well The well would be developed by surging, balling and over-pumping until the water reaches a degree of clarity. A typical well construction detail is presented in Figure 3 5.0 CLEAN-UP The area would be maintained in an orderly fashion Used materials and trash would be properly disposed daily Following completion of the work, the area would be restored to its original condition During times when operations have ceased, the well casing would be covered to protect the Integrity of the groundwater and the safety of the public 6.0 CHEMICAL TESTING PROGRAM Soil samples recovered from boring B-1 and well bore MW-4 would be chemically analyzed for total petroleum hydrocarbons as diesel (TPH-D), as gasoline (TPH-G), and benzene, toluene, ethylbenzene and total xylenes(BTEX) Analyses would be performed on soil samples from B-1 and MW-4 at the following depths 10, 15, 20, 30, 40, 50,'60 and 70 feet In addition, analyses would be performed on the soil sample at 75 feet and on the water sample from MW-4 The analyses would be performed for TPH-D using EPA Test Methods 3550 and 8015, for TPH-G using EPA Test Methods 5030 and 8015 and for BTEX using EPA Test Methods 602/8020 The detection limits for the analyzed fuel products for aqueous and solid matrix would be as presented in the State of California Leaking Underground Fuel Tank (LUFT) Field Manual The analytical work would be performed by the State-certified BSK Analytical Laboratories in Fresno RS/RAQ[I/p9221915ep1 11,1992 (m1ft\rrartp1a992) 3 . &Associates