2022-02-22_PERMIT FILE - C1980007 (5)

Home Browse Search

West Elk Mine 2.04-22 Rev. 11/04- PR10; 03/18- PR15; 01/22- MR459 central coal body, the E Seam splits into two distinct benches (E0 and E1) as the intervening rock parting thickens (Map 18). Further to the east and west, the upper (E0) bench of the E Seam maintains mineable thickness, ranging from 8.0 to 12.0 feet. The E0 bench thins to its mineable thickness limit of 8.0 feet and continues splitting and thinning further to the east and west. Within the Jumbo Mountain and most of Box Canyon lease areas, the E Seam was split and comprised of several thin (<5 feet) coal benches that are separated by rock partings. In these areas, these splits collectively form the E Seam "zone" as shown on the stratigraphic cross-sections (Figure 5A through Figure 5F). Because of the thin and erratic nature of these coal benches, the E Seam was considered un- mineable in the Jumbo Mountain and most of the Box Canyon lease tracts. Where the E Seam coal benches merge to form one thick seam, away from the influence of the split, the coal quality is generally good. This is because the upper (E0) bench is thicker and "cleaner" with fewer impurities than the lower (E1) bench, which frequently contains bony or shaley layers. The additional seam height will also allow top and bottom coal to be left during mining, which will improve product quality by reducing out-of-seam dilution. This thicker and higher quality E 100 Seam deposit was mined during the 1940's from the Oliver No. 2 mining operation (Map 18), and will likewise be mined locally within the South of Divide permit revision area. E Seam Reserves Mineable E Seam reserves are based on projected longwall mining heights ranging from 8 to 14 feet, dependent upon seam thickness and other operating constants due to reserve geology. As shown on the E Seam thickness map (Map 18), the mineable E Seam reserve is bounded on the northwest, east, and south by the thinning of the uppermost, E0 coal bench to 8 foot and less in thickness and the Mt. Gunnison laccolith. To the southwest, the E Seam reserve is restricted by outcrop. To the north, the E Seam merged with the underlying D Seam and was mined by the Oliver No. 2 Mine operation. The existing mined slopes that were used to access the B Seam from the F Seam workings are located such that they pass through the northern-most extent of the mineable E Seam reserve. Access to E Seam reserves are from these slopes south to the main body of the reserve and east and north to the existing shaft ventilation facilities. Mining of E seam longwall panels LWE1 through LWE8 was begun in late 2008 and was followed by mining of the Sunset Trail longwall panels LWSST1 through LWSST4, and longwall panels LWE14 through LWE16 as depicted on Map 51. Future E seam mining plans include longwall mining reserves in longwall panels LWE10 through LWE12 that are located above longwall panels B12, B13, and B13A. Mining plans also include mining of longwall panels B26 through B29 under already mined E seam panels E1 through E6. Projected reserves and quality are shown on the tables above. E Seam Overburden and Interburden E Seam overburden (Map 19), ranges in thickness from zero at the outcrop to about 1,200 feet in the east central part of the permit area. Average overburden thickness is about 800 feet within the West Elk Mine permit area.