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} Conestoga-hovers & Associates STANDARD WELL DESTRUCTION FIELD PROCEDURES This document presents standard field methods for destroying groundwater monitoring wells. The objective of well destruction is to destroy wells in a manner that is protective of potential water resources. The two procedures most commonly used are pressure grouting and drilling out the well. These procedures are designed to comply with Federal, State and local regulatory guidelines. Specific field procedures are summarized below. Pressure Grouting Pressure grouting consists of pumping neat Portland cement through a tremie pipe to the bottom of the well and filling the well casing with cement from the bottom to the.top. Displaced groundwater is contained at the wellhead and discharged into an appropriate container for disposal. The cement is composed of about five gallons -of water per'94 lb. sack of Portland Type I/H Cement. Once the well casing is completely filled with cement, 25 pounds per square inch of air pressure is applied to the grout column using an air-compressor. The process is continued until the grout column is stable under pressure. In some instances,the well casing can also be pressurized by extending the well casing to the appropriate height and filling it with grout. In either case, the additional pressure allows the grout to be forced into the sand pack. After grouting the sand pack and casing,the well vault is removed and the area resurfaced or backfilled as required. Well Drill Out When well drill out is required, the well location is cleared for subsurface utilities and a hollow- stem auger drilling rig is used to drill out.the well casing and filter pack materials. First, drill rods are dropped down the well and used to guide the augers as they drill out the well. Once the well is drilled out, the boring is filled with Portland cement injected through.the augers or a tremie pipe under pressure to the bottom of the boring. The well vault is removed and the area resurfaced or backfilled as required. i i i Well Destruction SOP t