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COAL RESERVE QUALITY ENHANCEMENT DRILL PROGRAM <br />INTRODUCTION <br />The New Horizon Mine coal reserves are based on approximately 115 boreholes drilled between the mid-1980's <br />and 2002 The bulk were drilled by Peabody Coal Company in the 1980's. Western Fuels -Colorado (WFC) <br />drilled about 55 holes from 1993 to 2002. Occasionally, WFC needs to drill infill holes within the existing array <br />to make more certain ofits'reserve estimations concerning various mining parameters such as coal quality, coal <br />and overburden thickness, etc. WFC anticipates that during the year 2004 such infill holes will be needed. <br />PROGRAM DESCRIPTION <br />The drill program will consist often mixed rotary and core holes completed to depths that range from 85 to 135 <br />feet (see Figure 2.05.3(3}10.3). The upper portion of each core hole will be air rotary drilled to about 2 feet on <br />top of the upper coal seam (UDX). A spot core of about 22 feet will be bored to about 2 below the lower coal <br />seam (LDX). All holes will be completed with a 15 to 20 foot air rotary subdrill below the LDX to allow for E-log <br />probing of each hole. Rotary hole diameter for the top portion will be between 4.5" and 5.5°, the outside core <br />diameter will be about 4.0" to 5.0", and the rotary subdrill will be between 3 718" and 5.5". <br />The equipment to be used will consist of a medium-sized single-wall air rotary truck mounted drill rig similar to <br />a Portadrill TKT or Failing CF-15. This type of rig is capable of drilling the spot cores needed. Support <br />equipment will include a 1500 to 3000 gal water truck, boom truck and drillers' pick-up. Actual equipment used <br />and drill hale dimensions will depend on the contractor selected to do the work. <br />EARTHMOVING REQUIREMENTS <br />All of the ten sites are on faidy level pasture ground that will require no road or site preparation. <br />DISTURBED AREA <br />Since there will be no earthmoving requirements, there will be no disturbed areas. <br />AQUIFER IMPACTS <br />Sec. 2.04.7 of the Permit states that the overburden, coal and underburden zones all have their own distinct <br />aquifers. <br />DRILL HOLE ABANDONMENT <br />The holes as currently planned are all within the mining envelope. Abandonment and closure will be by mining. <br />If mining ceases before closing the hole, or if a hole location is moved to be outside the mining envelope, then <br />those holes will be sealed with a pelletized bentonite product to ten feet above the static water level. The pellets <br />will be adequately sized to allow complete backfilling of the hole below the ten foot above water level line without <br />bridging. The top of the hole will be plugged with concrete from 3 feet to 13 feet below ground level. The holes <br />will not be developed as water wells. <br />Table 2.05.3(3) 10-4 show the worst-case estimated reclamation cost for drill hole abandonment. It is worst- <br />case because it assumes that mining will cease before any hole is closed by the normal mining process. <br />(Revised 03/04) Attachment 2.05.3(3)10- 15 <br />