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2.05.2 <br />The Bowie No. 1 mine existing and proposed coal mining procedures are designed to maximise <br />the utilization and conservation of the coal resources. To achieve this, Bowie Resources Limited <br />(BRL) uses the best technology currently available which will maintain environmental integrity. <br />All coal mining within the permit azea will be done by undergound methods. BRL anticipates <br />continued use of the room and pillar method of mining using continuous mining machines. <br />Mining practices are in accordance with recommendations of the U.S. Bureau ofLand <br />Management concerning Maximum Economic Recovery. The mining method currently employed <br />and planned for the mine is room and pillar mining with eventual pillar recovery for most of the <br />permit azea (refer to Permit Term and Long-Term Planning, Map 2-5, and Map 2-6). <br />Federal lease C-37210 stipulation "g" allows only limited mining within 0 to 600 foot overburden <br />depth buffer zones depicted on Map No. 2-5 and Map No. 2-9. Additional mining constraints, <br />developed as pillar stability design calculations, apply to the 600 to 800 foot overburden depth <br />buffer zones also depicted on Map No. 2-5. These additional constraints aze based upon <br />recommendations contained in the June, 1983 subsidence study conducted by Geo-Hydro <br />Consulting, Inc. (see Subsidence Appendix, Volume 3). <br />In compliance with BLM stipulation "g", access entryways will be developed only beneath the <br />• Steven's Gulch and East Roatcap Creek drainage buffer zones under 600 ft. of overburden. <br />Permanent protective pillars will be left standing to prevent all surface and subjacent distwbance <br />to the overburden. Protective pillars in these buffer zones will be designed to provide safety <br />factors in excess of 2.0 using the Wilson pillar design method (refer to Pillar Stability Calculations <br />in Volume 2). Panel designs for specific development geometries and mining heights vary within <br />these buffer zones and are optimized to provide maximum economic recovery of the coal <br />resource, however, the minimum safety factor criteria for all panels developed within these buffer <br />zones remains constant at 2.0. Secondary extraction or retreat mining is limited to the recovery of <br />floor coal within previously developed entries. All development entries are roof-bolted in <br />accordance with the approved roof control plan. <br />In the 600 to 800 foot overburden depth buffer zones, permanent protective pillars are designed <br />to provide safety factors in excess of 1.5 using the Wilson pillar design method. Panel designs for <br />specific development geometries and mining heights vary within these buffer zones and aze <br />optimized to provide maximum economic recovery of the coal resource, however, the minimum <br />safety factor criteria for all panels developed within this buffer zone remains constant at 1.5 (refer <br />to Pillaz Stability Calculations in Volume 2). Secondary extraction or retreat mining is limited to <br />the recovery of floor coal within previously developed entries. All development entries are roof- <br />bolted in accordance with the approved roof control plan. <br />Cyprus Orchard Valley Coal Corporation and its assigns shall indemnify the United States against <br />any liability for damage to life or property arising from the undermining of the Steven's Gulch <br />Road as proposed under technical revision 17 (Panel B) for Permit No. C-81-038. <br />TR-032 - 2 - 9/99 <br />2/8/co <br />