2008-03-21_PERMIT FILE - C1980007A (5)

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West Elk Mine Man-made surface structures exist on the coal lease area and within the South of Divide permit revision area (Exhibit 32B and Map 67). The only known man-made structures which are currently used (intermittent seasonal use) are Monument Dam - Minnesota Reservoir (Exhibit 74) and a cattle camp on the Dry Fork of Minnesota Creek with a wood-framed building on a concrete slab completed by the landowner in October 1994 and a smaller wood-framed building and livestock enclosure constructed in November, 1995 (see Exhibit 73). A deteriorated and collapsed cabin exists in Sylvester Gulch, and the remnants of soil and stone foundations of two buildings exist on a small bench overlooking the mine portal. The remains of three log structures, possibly a cabin, barn and shed, are located in Lone Pine Gulch. Several similar abandoned structures exist on the Jumbo Mountain lease tract (see Exhibit 1 OA and Exhibit 1013). Other abandoned structures in the permit area, are described in the Cultural Resources Reports in Exhibits 10, 10A, l OB, IOC, IOD, and 10E. Projected subsidence- related impacts to these "structures" are addressed under the permit section entitled "Effects of Subsidence and Mine-Induced Seismic Action on Man-Made Structures and Renewable Resources". Based on field evaluation of the West Flatiron lease area, there are no structures or renewable resource lands within the boundary of COC-67011. Known springs and renewable resource lands in the Raven Gulch drainage are not within the affected area associated with mining of the West Flatiron lease tract. The only notable man-made structure potentially influenced by mining activities within the least tract is Highway 133. The potential impact to this structure is indirect by reactivation of known landslides south of the highway and north of Longwall Panel 18A. Impacts from, and monitoring of, this potential reactivation are addressed under the worst possible consequences discussion associated with mine-induced subsidence under (Landslides) below. Monument Dam and Minnesota Reservoir - Though the coal underlying the reservoir and dam is not leased by MCC and is not planned to be mined, mining-related phenomena could have an impact on the dam structure and reservoir in it's current configuration 3-15-2006, at a factor of safety of nearly 1.0. The dam and reservoir lie outside the anticipated angle-of-draw of mining- induced subsidence (see Map 51 for the depicted angle of draw at 25 degrees). However, to make certain the maximum extent of subsidence will not impact the reservoir or dam, MCC plans to confirin the angle-of-draw in the SOD area while mining occurs in panels well away from the structures. A description of the plan to confirm the angle-of-draw is outlined in Section 2.05.6 (6)(e)(i)(D) - Detailed Description of Predicted Subsidence Phenomena, Subsection "Effects Of Subsidence And Mine-Induced Seismic Activity On Man-Made Structures And Renewable Resources", Monument . Dam - Minnesota Reservoir, item 1. MCC also proposes to initiate a significant survey program with horizontal and vertical control elements of the Minnesota Reservoir, Monument Dam, and the landslide located in the left abutment of the dam. This program is also described in Section 2.05.6 (6)(e)(i)(D) - Detailed Description of Predicted Subsidence Phenomena, Subsection "Effects Of Subsidence And Mine-Induced Seismic Activity On Man-Made Structures And Renewable Resources", Monumment Dam - Minnesota Reservoir. The purpose of the survey is to determine if there is any movement of the dam, reservoir basin ground surface, and landslide \vlule mining is taking place in the SOD area. E 2.06-108 Revised June 2006 PR10, Rev. Harch 2006; Rev. April 2006 PR10; A1aj, 2006 PR10, Arav. 2006 TR107, Sep. 2007 PR-12; Feb. 2008PR-12