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<br />3.4.A.10 LONG TERM PLAN <br />3.4.A.10.1 F Seam <br />The F seam portal locations are shown in Exhibit 3.2.7.A and are <br />within the existing mine site surface disturbed area. The initial <br />development of the portals began in 1981 concurrent with contruc- <br />tion of the Mt. Gu~inison No. 1 mine surface facilities. The Mt. <br />Gunnison Mine was originally permitted for mining from the upper <br />most mineable seam, the F seam. Mining has occurred in the F seam <br />from 1982 to present. The F seam mine was developed initially by <br />driving a series of life of mine main entries, nine main intakes <br />and seven main returns. Amine plan revision was submitted shortly <br />after mining began to turn the main entries to the southwest to <br />avoid an area along the margin of Sylvester Gulch of predicted poor <br />hydrologic and geologic mining conditions. Appendix B-3 contains <br />this mine plan revision which was approved by the Division. <br />Submains are developed off the main entries. From these submain <br />entries, productionz panels are developed. Exhibit 3.4.4.B.2 <br />included herein is a revised F seam mine plan and has been updated <br />in this submittal to reflect recent changes. The earlier Exhibits <br />are located in Volume 4 of the M & R Plan and were submitted with <br />t}~e Technical Revision to reduce Hydrology monitoring. Exhibit <br />3.4.4.B.1 shows the F seam life of mine plan. The most recent <br />~ approved version of this map is located in the Adequacy Response <br />Volume of the M & R Plan. <br />Room and pillar mining methods have bee~i used exclusively in the <br />F seam. To date, four productio~i panels off t-.he 1st West Submain <br />have been retreat mined. Panels projected to be retreat mined in <br />the F seam are skiown on Exhibit 3.4.4.B.2. This mine plan is <br />general in nature and depicts the expected layout and mineable <br />areas. Specific aspects of the mine plans must be adjusted as <br />necessary as mining progresses to allow for varying production <br />levels, mining conditions, varying coal quality and other related <br />factors and conditions. <br />Exhibit 3.4.4.B.2 shows an area in F seam projected to be mined in <br />association with B seam development. This area is in Federal Lease <br />D-044569, near the main intakes. This area was originally <br />projected to be mined in the first 5-year permit term. Subsidence <br />monitoring was initially planned for this area and later moved to <br />its current location. The mining projected in this area will be <br />of importance during excavation of the B seam slopes and ventila- <br />tion shaft. To avoid major interference during excavation of the <br />B seam slopes, it is planned to mine in the projected area and <br />possibly install a separate beltline for this ~sectioti. This would <br />• allow shipment of refuse material on the off-shift with minimal <br /> <br />