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coal from the longwall section and the subsequent caving of overlying strata may damage the well. The well casing may be collapsed or sheared as longwall panels are retreated beyond the location of the methane drainage well. The DMG recommends that the total depth of tho well be measured prior to initiating plugging procedures to determine if the well has been damaged. If the casing is damaged and the packer or plug cannot be set at the proposed depth, then a bridge plug/packer and cement plug should be placed at the -lowest point possible in the well, as close to the perforated casing interval as practicable. EXAMPLE OF TYPICAL METHANE DRAINAGE WELL COMPLETION AND ABANDONMENT The following discussion is provided as an example of an acceptable well completion and abandonment procedure for permanently sealing a methane drainage well. Well completions may vary, but typically are completed as shown in Figures 1 and 2. Hole diameters range from 9 inches to 15 inches. The total depth of the borehole generally ranges from 25 to 30 feet above the coal seam. The holes are completed with steel casing ranging from 5-1/2" to 9-5/8" in diameter to the projected fracture zone above the longwall mined panels. Generally, the bottom 200 feet of borehole is left open and uncased. The bottom 200± feet of casing is perforated, and the bottom of the perforated casing is left open and is not capped with an end plug. The well is completed with blank casing to the surface. At the top of the perforated casing a cement basket or other seal is placed and cement is pumped into the annulus above the seal, grouting the casing in place. In some instances (as shown in Figure 2), a smaller diameter, perforated casing is set below and overlaps inside the solid cased portion of the well. As the longwall panel retreats past the methane drainage well, the perforated casing is allowed to fall dropping no further than the bottom of the coal seam mined. Abandonment procedures may also vary due to site conditions or completion specifications. After consideration of internal and external comments received in response to initial drafts of this document, the following procedure is thought to be most effective to control gas from migrating upward through the inside of the casing or through the annulus (between well casing and borehole) to the surface. An example of a methane drainage well after abandonment is shown in Figure 3. In this case, a bridge plug is placed immediately above the perforated casing to create a foundation for cement slurry fill. A tremmie pipe is recommended to ensure a continuous pour of the cement slurry from the top of the bridge plug to the ground surface. In this case, the entire solid cased portion of the well is filled with cement slurry. 5