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well cap was installed on each well head This design discourages vandalism and reduces the possibility of accidental or unauthorized disturbances of the well 5 2 1 Vapor Extraction Well Construction A 4-inch diameter vapor extraction well was constructed in soil boring B-5 to conduct a feasibility vapor extraction pilot test The well was constructed of threaded PVC casing to a total depth of approximately 25 5 feet The screen interval consisted of factory-perforated 0 10-inch-wide slots and extended from near the base of the soil boring to a depth of approximately 6 0 feet below grade The annular space was backfilled with washed pea gravel to a depth of approximately 4 feet below ground surface A 1-foot thick, hydrated bentonite chip plug was placed above the gravel pack, and the remaining annulus was backfilled with neat cement containing <5%bentonite powder The wellhead was designed and completed in a manner similar to that of the monitor wells The location of the vapor extraction test well is shown on Figure 3 5 2 2 Groundwater Sampling Following monitor well construction, each groundwater monitor well was surged with a vented surge block and groundwater in each well was subjectively inspected by lowering a clean bailer to the groundwater surface and retrieving a groundwater specimen The water was examined for floating product, sheen, or odor None of the monitor wells showed evidence for floating product or sheen, however, a strong odor emanated from monitor well MW4 and a moderately strong odor was detected in groundwater retrieved from monitor well MM3, no odor was detected in groundwater from monitor well MW2 All three of the wells were then developed by extensive pumping until three to five well volumes of groundwater were purged from each well, and stable field readings of pH, specific conductivity, and temperature were obtained(Table 4) The existing monitor well MW 1 was not purged or sampled SEACOR 014-01-1 par 8