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10/21/2004 13:07 19709295177 OXBOW MINE PAGE 05/09 ~Satiae• 2.05.3 workings. Founeen Sanborn Creek Mme borehole locations are shown on the General Facilities Map (Map 2.05•Ml, Sheet 4 of 6). Elk Creek Mme borehole locations are shown on General Facilities Map (Map 2.05-M1, Sheet 6 of 6). Exhibit 2.04-E3, Item 9 provides a summary all of the OMLLC merl+anr dtaiaage wells. Hydrologic considerations for "typical° borehole locations are found in Exhibit 2.05-E3, Section 9. ` Each gob vent borehole or groupp of boreholes will be permitted separately as minor or technical xevisions. Revision submittals wr71 address specific details relative to location, access, resource protection, and drainage and sediment control. Surface disturbance associated with these borehole activities is limited to light-use roads utilized to access the well sites and graded pad areas utilized for dulling activities and installation of surface degasification equipment. Well sites have been selected to m~ni..,i~r new surface disturbance, whew possible. Well sites can often be accessed using existing unimproved powerline, mach roads or exploration roads. Minor road improvements such as grading and wrdeming m certain areas may be necessary to provide for drill and equippment access de 'endent on existing road conditions. In addition, dependent on survey results, the actual d~ site maybe beyond the limits of existing roads, requiring toad extenstong. To the extent feasible, borehole sites ate located so that access roads can provide access for one or more degasificarion installations. WeA pad 2reas arc typically a maSimum of lOD' x 200'. If multiple wells arc drilled from the same pad, the dimensions of the pad will be larger, but typically will be less total disturbance than the sum of dte individual pad dimensions. Site development involves the minor road improvements noted above, cstablisbment of temporary upslope drainage diversion (if necessar}~ to carry runoff around the pad area, site cleazrttg, removal and windrowing of topsoil (or suitable soil material) in stockpiles ox a berm oa the perimeter of the pad area, grading of the pad area, and excavation of temporary mud prts for conta~~mr*+t of drilling fluids d drilling activities. WeILS will be drilled to a depth of up to 2,500 feet below the ground surface to intercept the mine workings or seam to be mimed. A conventional truck mounted rotary drill rig is typically utilized to drill the well using rotary air, foam, and/or wet (nerd) drilling methods to advance and maintain the physical iategrtty of the well The wells have been and wr11 be cased with conventional grouted steel casing for the entire length except fox the portion of the borehole extending from approximately 200-feet above and into the mine workings, which is cased with perforated steel casing to max,m,~m gas exmaction. Gan extraction is achieved by connecting a trader mounted vacuum pump to the well(s) that creates a negative resstrre, drawing methane and other gases from the mine workings to and through the well). The vacuum pump is as-powered, utilizing the methane extracted through the wall as the prizr>ary fuel source and propane as the start-up fuel source for initial well pressurization. Any excess methane not utilized to fuel the dcgavification pump is vented or in the future maybe flared-off or used in a small power generator. The degasification installations wAl continue to be operated so long as needed to prevent or minimi~r methane in the mine and/or seepage of methane from the sealed mice workings into active mine arras. The degasificatiom installations are inspected on a periodic basis and the associated light-rue road and operating equipment aze maintained as necessary to assure continued effecnve operation. Whew the degasifuauon installations are no longer required, surface facilities and eqqutuupment will be removed and associated surface disturbance areas wrll be reclaimed as described in the reclamation plan section Pre-e~dsting um~mproved public roads and roads requested to be left in place by surface owners maybe retained. To prevent leakage of rvetlrane, a seal or plug will be placed is the casing as deep as possible and the well string filled with cement to wnhm 10 feet of the surface. The AMG Methane Azainage and Momtoriag Well guidance document is a good source of guidance and wr71 be consulted in accordance with Rule 1.1.5.4. If a borehole is to be retained as a methane producxion well, it wr71 be permitted with the Colorado Oil and Gas Conscrvatiom Commission.