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Groundwater monitoring wells will be completed by installing 2-inch diameter, flush-threaded, Schedule 40 PVC casing with 0.020-inch factory-slotted screen. Approximately 20 feet of screen will be placed in the bottom of the boring and will extend from approximately 5 feet above to approximately 15 feet below first-encountered groundwater. An RMC 2/12 sand pack, or equivalent, will be placed in the annular space across the entire screened interval, and will extend approximately 2 feet above the top of the screen for the well. A 2 foot bentonite transition seal will be placed atop the sand pack, and a Portland cement seal will extend from the bentonite transition seal to the ground surface. The Portland cement seal will be emplaced by tremie pipe or through the center of the hollow-stem augers in one continuous operation from the bottom of the interval to be filled to the top. Emplacement of the Portland cement grout specifically shall not be accomplished by "free fall" from the ground surface. The boring logs will show well construction details. The groundwater monitoring wells will be developed after completion. The development proce- dure for each well will consist of pumping or bailing water from the well until the water is visibly clear, the well goes dry, or until a maximum of ten casing volumes have been removed. Organic Vapor Procedures Soil samples collected at 5-foot depth intervals during drilling will be analyzed in the field for ionizable organic compounds using a flame-ionization detector (FID) or a photo-ionization detector (PID) with a 10.2 eV lamp. The test procedure will involve measuring approximately 30 grams from an undisturbed soil sample, placing this subsample in a ZiplockTM-type bag or in a clean glass jar, and sealing the jar with aluminum foil secured under a ring-type threaded lid. The container will be warmed for approximately 20 minutes (in the sun), then the head-space within the container will be tested for total organic vapor, measured in parts per million as benzene (ppm; volume/volume). The instrument will be calibrated prior to drilling. The results of the field testing will be noted on the boring logs. FID/PID readings are useful for indicating relative levels of contamination, but cannot be used to evaluate hydrocarbon levels with the confidence of laboratory analyses. Laboratory Analysis of Soil and Groundwater Samples Analysis for total petroleum hydrocarbons calculated as gasoline (TPH-g) will be performed by modified EPA method 8015. Analysis for benzene, toluene, ethylbenzene, and xylenes (BTEX compounds) and methyl-tert butyl ether (MtBE) will performed by EPA Method 8020. The presence of MtBE in soil samples will be confirmed by EPA Method 8260. No additional oxygenate analysis of soil samples will be conducted based upon non-detection of DIPE, ETBE, TAME, TBA, 1,2-DCA, EDB, methanol and ethanol in excavation soil samples. Oxygenates including MtBE and ethanol, and 1,2-dichloroethane (1,2-DCA) and ethylene dibromide (EDB), will be analyzed in groundwater monitoring well samples by EPA Method 8260. Methanol analysis will be conducted using EPA Method 8015 Modified for industrial solvents. Samples from stockpiled soil will be analyzed for total lead using EPA Method 6010. If total lead exceeds 50 parts per million in soil samples they will be analyzed for STLC lead. \\SACRFP 1\COMMON\rancfp 1\Proj ects\Projects\880\040\1 a\0102\880040_wp.doc