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The Seneca II -W Mine is a surface mine operation. The mine was a dip - slope, area strip mine <br />utilizing conventional dragline mining methods. In addition, auger mining was employed in <br />certain locations. The mine area permit boundary includes three separate areas (North Block, <br />South Block, and South Extension) and associated facilities. The north and south blocks comprise <br />the "original mine permit area", while the South Extension was a permit area expansion approved <br />within PR -2. Mining was completed and coal extraction at Seneca II -W ceased in early January <br />2006. The final areas mined were the Wolf Creek and Sage Creek seams in the South Extension <br />Area; mining had been completed in the original permit area several years previously. <br />Within the original permit area, Mine Pits A, B, C, and D were oriented perpendicular to the <br />cropline and the coal in the mine pit area dipped approximately 18 to 25 %. A single dragline <br />operated alternately within the north and south areas. The Wadge coal seam was mined in all four <br />pits from the cropline to approximately 100 feet in depth. Auger mining was conducted within <br />certain final Wadge pit locations in the original permit area. <br />Mining in the south extension area was approved in PR -2 and subsequently initiated. <br />Development of this area proceeded directly from the final cut in the A pit. Wadge Coal pit <br />extraction and progressive development was parallel to the cropline. Mining was constrained by <br />the rapid increase in overburden depth as mining progressed away from the cropline. The Sage <br />Creek/Wolf Creek pit progressive development was for the most part perpendicular to strike, and <br />proceeded pit by pit from south to north within the South Extension Area. Dragline operations <br />within the South Extension Area alternated between the Wadge and Wolf Creek/Sage Creek pit <br />areas. Highwall miner operations were proposed within PR -4, for final Wadge Pit highwall <br />locations, and various Wolf Creek/Sage Creek pit locations of the South Extension Area, but the <br />plans were not implemented and were withdrawn by PR -5. The operation plan is addressed in <br />detail in Volume 7, Tab 12. <br />The permit application provides detailed information on mining and reclamation operations, <br />transportation routes, and hydrologic controls for the mine. <br />Coal mined was owned by private interest and the Federal government, under lease to Seneca <br />Coal Company. Surface ownership includes federal lands managed by the BLM, a variety of <br />private leases, subleases and easements. <br />The total permitted area, including the tie - across haul road, is approximately 4,093 acres. The <br />maximum proposed disturbed area is 1,534.5 acres, including both the mine area (1,334.5 acres) <br />and Tie Across Haul Road Area (200 acres). The permit area and areas approved for disturbance <br />will be reduced to 3,878.5 and 1,334.5 acres, respectively. The disturbed area includes the mine <br />pit area, surface support facilities, haul roads and drainage control facilities. In addition to the <br />primary disturbance areas described, various exhibits and text refer to a number of "minimal <br />disturbance" areas, totaling approximately 56 acres. These areas are primarily located along <br />ephemeral drainages between primary disturbance areas and sedimentation ponds, and could <br />potentially be impacted by sediment deposition or erosion, and associated maintenance activity. <br />Seneca II -W Findings Document 11 C- 1982 -057 <br />Permit Revision No. 6 January 6, 2012 <br />