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i Project No 58100-06-1 IA June 29, 1995 3 14 Disposition of Drill Cuttings ' Drill cuttings generated from the drilling operations were placed in DOT 17-H 55-gallon drums and stored onsite pending the receipt of analytical data and subsequent disposal following regulatory protocol ' 32 MONITORING WELL INSTALLATION ' 32 1 Vapor Well Construction and Materials Vapor Well VW-1 was installed within the former UST excavation to a depth of approximately 212 meters (69 5 feet) bgs The well was constructed using 101 6-mm (four-inch) diameter Schedule 40 ' polyvinyl chloride (PVC) casing The lower portion of VW-1 was constructed using approximately 16 8 meters (55 feet) of 2 54-mm (0 10-inch) slotted screen PVC casing between depths of approximately 4 4 to 21 2 meters (14 5 to 69 5 feet) bgs A filter pack consisting of pea gravel was placed around the screen ' from the bottom of the boring to an elevation of 0 3 meter(one foot) above the screen zone A 0 6 meter (two foot) thick seal consisting of hydrated bentonite chips was placed above the filter pack An 304 8- mm (twelve-inch) diameter, traffic-rated security wellhead cover set in a concrete pad was used to complete construction Well construction details are recorded on the boring/well logs presented in Appendix B 3 22 Monitoring Well Construction and Materials Wells MW-4 through MW-8 were located 12 8 to 22 9 meters (42 to 75 feet) from the perimeter of the ' former UST excavation and installed to a depth of approximately 22 9 meters (75 feet) bgs The monitoring wells were constructed using 101 6-mm (four-inch) diameter Schedule 40 polyvinyl chloride (PVC) casing The lower portion of the wells were constructed using 4 6 meters (fifteen feet) of 0 5-mm (0 020-inch) slotted screen PVC casing placed between the approximate depths of 18 3 to 22 9 meters (60 to 75 feet) bgs A filter pack consisting of No 3 Monterey sand was placed around the screen from the bottom of the boring to an elevation of 0 6 meters (two feet) above the screen zone A 0 6 meter (two ' foot) thick seal consisting of hydrated bentonite chips was placed above the filter pack A 304 8-mm (twelve-inch) diameter, traffic-rated security wellhead cover set in a concrete pad was used to complete construction Well construction details are recorded on the boring/well logs presented in Appendix B ' 3 23 Groundwater Well Development Monitoring wells were developed using a surge block to density the sand pack prior to placement of the bentonite seal Pumping to remove sediment and groundwater was accomplished using a 50 8-mm (two- inch) diameter Grundfos electric submersible pump ' 3 2 4 Well Survey The elevations of the top of each well casing were surveyed by a Geocon registered civil engineer relative to monitoring well MW-1 casing elevation of 6 55 meters (21 49 feet) above Mean Sea Level (MSL) as 6