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desired completion interval, establishing bentonitic plugs above and below the screened interval and grouting <br />the well annulus to prohibit vertical migration and cross-contamination of aquifers, and developing the well by <br />successively flushing and pumping the well bore. Figure 2, Typical Monitoring Well Completion, illustrates <br />typical completion methods. <br />If an exploration drillhole is converted to a monitoring or water-supply well, a detailed well completion report <br />and diagram will be forwarded to the appropriate agencies. L` the well is completed for water-supply <br />purposes, the appropriate water rights filings will be made with the State Engineers Office. Once the well is <br />no longer needed, it will beplugged and sealed. <br />Pronosed Reclamation Methods -The proposed exploration program is designed to minimize new surface <br />disturbance by utilizing existing roads and trails to the extent possible, placing drill pads adjacent to existing <br />roads, utilizing previously disturbed azeas for drill pads, and limiting pad size. Surface disturbance, and <br />reclamation requirements and costs are summarized by Table 2. The following sections describe the specific <br />proposed reclamation practices to be used to return exploration disturbance to a stable condition and <br />productive use. <br />Drillhole or Well Plueaing, Sealin¢, and Abandonment -All drillholes will be plugged, sealed, and abandoned <br />unless they are converted for long-term use as monitoring or water-supply wells. DrilIholes will be plugged <br />with a minimum of 6 cubic yazds (about 700 feet) of cement sluny. The cement slurry will be tremied into the <br />drillhole from the bottom of the hole, up through the target units. This will effectively plug and seal all coal <br />beds and potential groundwater aquifers to prevent vertical groundwater migration and cross-contamination of <br />aquifers. <br />Any remaining open drillhole interval will be filled with other suitable plugging material (plug gel or vendor- <br />specific grout compounds) and/or drill cuttings to within 5 feet of the ground surface and the drillhole will be <br />sealed with a surface plug consisting of at least 5 feet of cement. Information on potential plugging materials, <br />that aze generally superior to conventional cement grout, is provided in Appendix D. Surface casing will be <br />cut-off at or below grade. Reclaimed drillhole locations will be marked with either a steel fence post or a <br />metal survey cap at or below ground level (used where agricultural cropping occurs). All drillhole locations <br />will be accurately surveyed, and distinctly numbered, allowing for future identification. Abandonment reports <br />will be prepared and filed, as required by applicable regulations. When no longer needed, monitoring or <br />water-supply wells will beplugged, sealed, and abandoned in essentially the same manner, with the stipulation <br />that cement slurry will be used for plugging the well. <br />Exnloration Site Reclamation -Following completion of exploration activities (drilling, sampling, and <br />geophysical logging, or trenching) for each exploration site, any drillholes not converted to monitoring or <br />water-supply wells will be plugged, sealed and abandoned, as previously described, and exploration <br />disturbance will be reclaimed. Site reclamation will follow completion of exploration activities for each site <br />as soon as reasonably practical, recognizing however, that certain reclamation activities may be coordinated to <br />take advantage of equipment and personnel availability. Seeding of reclaimed exploration sites will occur <br />during the first favorable seeding period (typically late fall (preferred), or early spring) following completion <br />of site reclamation. The following summarizes the steps and general sequence for reclamation of exploration <br />disturbance azeas: <br />1) On completion of exploration activities at a given site, all trash, debris, and exploration equipment and <br />supplies will be removed from the site. <br />2) Fordrill-sites, excess drilling fluids may be pumped from mud pits for ofT site disposal, and the mud <br />pits allowed to dry-out. Mud pits or excavated trenches will be backfilled with the excavated material <br />and compacted to minimize any settling. Any excess drill cuttings will be spread over the drill pad, and <br />drill pads, trenched areas, and any new access road segments graded to approximate their original <br />configuration and blend with the adjacent terrain. <br />G:\Environmental\EXP[ARATION WORK\EXPLR 2006 B1G ELK\Big Elk 2006 NOI App. Form.doc Page 13 of 17 <br />