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CAMBRIA <br /> STANDARD FIELD PROCEDURES FOR ABANDONING MONITORING <br /> WELLS <br /> This document presents standard field methods for abandoning ground water monitoring wells. The <br /> objective of well abandonment is to destroy wells in a manner that is protective of potential water <br /> resources. The two procedures most commonly used are pressure grouting and drilling out the well. <br /> These procedures are designed to comply with Federal, State and local regulatory guidelines. <br /> Specific field procedures are summarized below. <br /> Pressure Grouting <br /> Pressure grouting consists of injecting neat Portland cement through a tremie pipe under pressure <br /> to the bottom of the well.The cement is composed of about five gallons of water to a 94 lb. sack of <br /> Portland I/II Cement. Once the well casing is full of grout, it remains pressurized by applying <br /> pressure with a grout pump. The well casing can also be pressurized by extending the well casing <br /> to the appropriate height and filling it with grout. In either case,the additional pressure allows the <br /> grout to be forced into the sand pack. After grouting the sand pack and casing, the well vault is <br /> removed and the area resurfaced or backfilled as required. <br /> Well Drill Out <br /> When well drill out is required, a hollow-stem auger drilling rig is used to drill out the well casing <br /> and pack materials. First, drill rods are dropped down the well and used to guide the augers as they <br /> drill out the well. Once the well is drilled out, the boring is filled with Portland cement injected <br /> through the augers or a tremie pipe under pressure to the bottom of the boring. The well vault is <br /> removed and the area resurfaced or backfilled as required. <br /> i <br /> E <br /> j <br /> } <br /> k Page 1 of 1, <br />