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BC&D Property Fhase H-Ground Hafer Assessment Proposal Page: 5 Vi 4.5 Disposition of Soil Boring Cuttings ' Since drilling will be done outside the soil contamination,drill cuttings will be land spread in the dirt area on the north side of the property. 4.5 Monitoring Well Design Monitoring wells for the upper aquifer will extend to a depth of 15 feet and will be constructed of 2-inch threaded-joint PVC pipe(schedule 40)that's perforated From the ti bottom of the well to a depth of 5 feet. Medium aquarium sand will be used to create a filter pack that extends from the bottom of the well to 2 feet above the perforated zone A bentonite grout(Quik Cel/Benseal mix)will tie emplaced above the filter pack in the annular space by using the tremie method. The monitoring well will be secured and a surface seal obtained by cementing in a water tight well box and a locking cap. . Construction of this type of monitoring well is iilustrated in Figure 5: Monitoring wells designed to test the second aquifer will be constructed as follows: the upper aquifer will be isolated by an 8-inch casing(schedule 80 PVC). Hollow stem tiJ auger drilling will be performed through this a-inch casing. Continuous soil sampling will be done to evaluate the strata. The boring will terminate into the second aquifers _ lower bounding clay layer.The well will be constructed of 2-inch PVC pipe(schedule 40),perforated with 0.04 inch slots up to about one foot above the top of the aquifer. Filter pack will be made of medium aquarium sand and a bentonite annular seal placed above the filter pack. The well will be secured with a locking well cap,water tight well cover and a concrete surface seal(about 3 feet deep). 4.7 Monitoring Well Development Each monitoring well will be developed before a water sample is collected. This will be accomplished b um m until clear groundwater is obtained and then removing an A iYp pumping g additional 5 well volumes. Where time-endurance sampling procedures are used, i . ground water will be pumped over a period of several hours with samples being ,. collected periodically throughout the course of pumping. The extracted ground water will be stored in 55-gallon drums until it's detennined if the water is contaminated. Contaminated water will be treated during the ground water remediation program. After permission is obtained from the County,uncontaminated water will be released into the city storm drain system.