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i I STANDARD FIELD PROCEDURES FOR MONITORING WELL DESTRUCTION This document presents standard field procedures for properly 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 injecting neat Portland cement through a tremie pipe under pressure to the bottom of the well.The cement is composed of about five gallons of water to a 94 pound sack of Portland 1/II Cement. Once the.well casing is full of grout,it is pressurized for five minutes by applying a pressure of 25 pounds per square inch(psi) with a grout pump. 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(or other appropriate) drilling rig is used to drill out the well casing and filter pack materials. First, drill rods are placed down the well and used to guide the augers as they drill out the well. A guide auger is used in place of the'drill rods if feasible. Once the well is drilled out, the boring is filled with Portland cement injected through the augers or a tremmie pipe under pressure to the bottom of the boring. The Well vault is removed and the area resurfaced or backfilled as required. Waste Handling and Disposal Soil cuttings from drilling activities are usually stockpiled onsite and covered by plastic sheeting. At least three individual soil samples are collected from the stockpiles and composited at the analytic.laboratory. The composite sample is analyzed for the same constituents analyzed in the borehole samples in addition to any analytes required by the receiving disposal facility. Soil cuttings are transported by licensed waste haulers and disposed in secure,licensed facilities based on the composite analytic results. s 161556(15} C-1 CONESTOGA—ROVERS&ASSOCIATES ; I 1