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' 12 water to enter the SnmulprobeTM under the depth-specific hydrostatic pressure After wanting approximately 1/2-hour for the Sunulprob6m to fill v nth water, it was repressurized with nitrogen gas to nummve potential infiltration of borehole water as it was raised through the augers The Snmulprobe m was depressurized at the surface, and a short length of 5116-inch OD Teflon tube was inserted through the bottom of the reed valve to drain and collect a water ' sample from the bottom of the Water Canister (Figure 4-1) The groundwater samples were stored in clean, glass jars provided by the on-site mobile laboratory and returned to the on-site ' mobile laboratory under proper chain-of-custody protocol for possible analysis Following collection of the water sample, the Sinulprob6m core barrel was then disassembled and the ' soil core removed The soil samples were preserved and evaluated following the procedures described above 4.2.4 Groundwater Well Installation Based on the analytical results from the soul and water samples collected using the Sunulprobe m, groundwater monitoring well NP-1 was constructed using 1-inch diameter, schedule 40 PVC casing The slotted (0 01 inch slot size) section extended from approximately 90 feet bgs to 85 feet bgs The sand filter pack, consisting of clean#2/12 sand, ' was placed adjacent to the slotted section and extended approxunately two feet above it Approximately four feet of bentonite pellets were placed above the sand filter pack and ' hydrated Well NP-1 was originally proposed as a nested well, with the second screened interval proposed from 60 to 50 feet bgs However, initial placement of the cement/bentonite ' grout, used as a seal between the two wells, resulted in a grout smear of the borehole wall to approximately 57 feet bgs The second nested well(50 to 60 ft bgs screen) was therefore not installed in the borehole and the remaining annular seal was filled with cement/bentonite grout A flush-mounted, traffic-rated well protection(Christy) box was installed at the surface with a ' watertight, locking cap to preclude tampering ' In order to replace the proposed second nested well, another groundwater monitoring well (MW-10)was installed approximately 5 feet away from well NP-1 Due to its proximity 1