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threaded end cap will be placed at the bottom of the PVC which will then be set through the auger The screened PVC casing will consist of 0 02 inch machine-cut slots Number 3 sand (or equivalent) will be poured down the auger while removing approximately 2 feet of auger at a time The filter pack will be placed 2 feet above the screened interval Three feet of bentonite pellets will be poured through the augers to form an annular seal A cement mixture will be used to fill the annular space to one foot below grade Traffic-rated, flush-mounted well boxes will be installed at a height of approximately 1 inch above grade to minimize the potential for surface runoff entering the well Park proposes to place the slotted interval of the well casing no greater than 15 feet below the static groundwater level Park requests to deviate from the state guidelines to 1 extend the screened interval 15 to 25 feet above the groundwater level, depending on the soil conditions encountered during drilling This would allow the wells to be used for groundwater�monitoring ' and to be potentially used for vapor extraction remediation of the vadose zone and capillary fringe 3.7 Well Development Each groundwater monitoring well will be developed using a surge block for at least 20 minutes, ' and then purged of at least three well volumes of groundwater During purging, values of pH, conductivity and temperature will be monitored and recorded The well will be allowed to stand for a sufficient period of time for the groundwater to equilibrate within 80 percent of static groundwater level prior to sampling 3.8 Groundwater Sampling Groundwater samples will be collected after the well has sufficiently equilibrated to static groundwater levels In the event that the wells are not sampled within 24 hours of well development and purging, each well will again be purged with a bladder or submersible pump until at least three well volumes have been removed Groundwater samples will be collected using a teflon or new disposable bailer and placed in the appropriate containers in the appropriate manner The samples will be placed in a cooler at 4 degrees centigrade or less and transported to a Iaboratory under proper chain of custody documentation 3.9 Groundwater Analyses ' Analyses of the groundwater will be performed by a California certified laboratory in'accordance with State guidelines and EPA protocol The groundwater samples will be analyzed for TPH, BTEX and total lead using EPA methods 8015, 8020, and 7421, respectively In addition to ' samples from each well, one equipment blank and one field duplicate will be collected and analyzed for the same chemical constituents A 1125x2 wp 6