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depth of 60 feet bgs where a 35 -foot thick clay/shale layer was encountered from 60 to 94 feet bgs. Beneath the clay/shale layer, sand was observed from 94 to 98 feet bgs. For estimating purposes, we have assumed the conductor casing will be set at 65 feet bgs and the well will be completed at a depth of 98 feet bgs. The actual completion depths of this well will be determined based on lithology encountered in the field. The deeper boring will be continuously cored beginning at approximately 30 feet bgs to the final completion depth to reduce the risk of cross contaminating water bearing formations. The proposed well construction details for the deeper monitoring well are included as Figure 6. The shallow monitoring well will be completed at a depth of approximately 27 feet bgs and will be placed approximately five feet from the deeper well. It is anticipated that a 0.01 -inch slotted screen will be placed from 7 to 27 feet bgs. The proposed well construction details for the relatively shallow monitoring well are included as Figure 7. Air Sparge Well One 2 -inch diameter air sparge well will be completed to a depth of approximately 32 feet bgs. It is anticipated that a 0.01 -inch slotted screen will be placed from 27 to 32 feet bgs. The proposed well construction details for the air sparge well are included as Figure 8. All six wells will be constructed of 2 -inch inside diameter PVC well screen and casing. To protect the integrity of the wells, locking, water -tight well plugs will be installed on each well, and water- tight, traffic rated, wellheads labeled "monitoring well" will be concreted over each well. The top of casing of the new wellheads will be surveyed to assess groundwater gradient and flow direction. All drill cuttings will be stockpiled on plastic sheeting on site pending laboratory results. It is estimated that the well installation activities will require four days to complete. Monitoring Well and Sparge Well Development Subsequent to well installation, the newly installed monitoring wells and the air sparge well will be developed using surge and bail techniques until the produced water is relatively sediment free. Prior to the collection of groundwater samples, a minimum of three well volumes (casing and sand pack) will be purged. Temperature, pH, water elevation, and electric conductivity will be measured and allowed to stabilize. Water samples will be collected from the monitoring wells only using disposable bailers, one dedicated to each well sampled. Groundwater samples collected from the two monitoring wells will be submitted using chain -of - custody record to a State -certified laboratory. Groundwater samples will be analyzed for TPHg and BTEX using EPA methods 8015/8020. Development/purge water will be stored in drums on site pending laboratory results. • W:\94326\REPORTS\WRKPLN.D0C 4 SMTH