2007-11-16_PERMIT FILE - C1981044A

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stored in rock disposal rooms located immediately south of the ramps to the east and west of main entries. This was done in accordance with plans approved by the Division. Longwall panels in the No. 5 and the No. 6 mines were and will be oriented along the dip of the "F" and "E" coal seams. Typical panel dimensions for the No. 5 mine was from 600 to 700 feet wide and varies in length from 2,500 feet to over 4,500 feet. In the No. 6 mine, panel widths will vary from 600 to 800 feet wide and will vary in length from 2,500 feet to 7,000 feet. Longwall mining experience gained from the mining of the No. 5 mine will be used and may result in minor changes of the mine plan for the No. 6 mine. EC anticipates [hat overall extraction in the longwall areas will exceed 80 percent. This is considered to be very good recovery for an underground coal mine. Utilization of longwall equipment for coal extraction allows complete extraction of the coal within the working limits of the machine. Geological structures may limit face height and maximum equipment height, {i.e. strong cleats, rider seams, sandstone channel margins). The only coal not recovered in a longwall mining operation is the coal left in various barriers, or roof and floor coal that is outside the cutting range of the shearing machine. Barriers will be left a[ the No. 5 and No. 6 mines for a variety of reasons. Those reasons are: • Protection of Main Entries • Property Boundary Barriers • Outcrop Barriers • Subsidence Barriers Protection of Main Entries. Experience at the Eagle mines indicated that main entry protection barrier pillazs of approximately 200 feat are adequate to provide the necessary protection of the main entries. If conditions indicate that greater or less protection is required, EC will adjust the width accordingly. Main entry barriers along Big Bottom will also be sized to protect AVF areas and the Yampa River. Property Boundary Barriers. Property boundary barriers will be left to ensure that the subsidence angle of draw does not cross the permit boundary and that mining will not occur closer than 50 feet from an adjacent owner's property line. Ou[cron Barriers. EC intends to leave a minimum barrier of 100 feet between the coal working and the coal outcrop. This outcrop barrier is necessary to minimize the subsidence effects along the outcrop and also serves to keep the mine ventilation system intact and prevent the extraction of oxidized coal along the outcrop. In areas where daylighting occurs, the area will be prepared in the following manner. Topsoil, if available, will be stripped, stockpiled, and re-vegetated with the approved topsoil stockpile seed mixture. The area to be disturbed will be approximately 200 feet X 400 feet, with the topsoil stockpile, overburden stockpile, and daylighted entries contained in [he area. If the daylighting occurs in favorable field conditions, an area will be excavated around the entry. In unconsolidated material, [he slope will be 2H:1V and in consolidated material about .25H:1V. A continuous miner will then daylight into the prepared area. If daylighting occurs in unfavorable field conditions, the continuous miner will daylight and the site will be prepared as described above when conditions allow. When this situation arises, an area of 20 feet X 25 feet will be disturbed prior to site preparation. The daylighted entry will be fenced to keep large animals out. Adequate warnings signs will be placed around the site(s) to alert the public [he entry are part of a mining operation. These daylighted entries will be incorporated into the mine ventilation plan. The daylighting procedure described above is a general plan and EC will submit a minor revision to the Division prior to undertaking any daylighting. The minor revision request will be submitted when [he mining unit is within 100 feet of daylighting. Permit Revision 04-34 2.05-3 Revised 7/2/04