2015-08-18_PERMIT FILE - C1982056A (4)

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The Eastern Mining District area sedimentary strata are not disturbed by any significant faults. The structural and lithologic characteristics of the permit area are depicted on Geologic Cross Sections B -B' (east -west) and D- D' (north- south), Figures 1B and IA, respectively. These figures are considered confidential. EMD (Panels 2 -Right through 6- Right, PR97 -04) _The mine inflow predictions were generated using a different methodology than was used for the EMD. The discussion and calculations are presented in Section 2.05 of this application. The methodology used a mirror -well technique, which should be adequate for predicting inflows into the mine. NORTH MINING DISTRICT (PR99 -05 and PR06 -07) The mine inflow predictions were generated using a different methodology than was used for the EMD. The discussion and calculations are presented in Section 2.05 of this application. The methodology used a mirror - well technique, which should be adequate for predicting inflows into the mine. NMD (Panels 17 -Right through 25- Ri2ht, PR03 -06 and PR06 -07) - The mine inflow predictions were generated using a different methodology than was used for the EMD. The discussion and calculations are presented in Section 2.05.6(3) of this application. The methodology used a mirror -well technique, which should be adequate for predicting inflows into the mine. WESTERN MINING DISTRICT (WMD, Panels 12 -Left through 17 -Left, PR06 -07, TR08 -64, PR09 -08) Because it falls within the Twentymile Park Basin, the geology of the WMD is similar to the previously permitted areas. The Twentymile Park synclinal axis, oriented NE -SW, is the northern boundary of the WMD, the area is bounded on the east by one of the primary faults (orient NNW to SSE), the western boundary is the Tow Creek Anticline and Hayden Syncline, and the SMD lies along the southern limit of the area. General surface geology and coal seam structure for all mine areas are shown on Maps 5, and 6 (Confidential), respectively. With the exception of the primary fault that extends through the eastern portion of the WMD, the WMD sedimentary strata are not disturbed by any significant faults. The structural and lithologic characteristics of the permit area are depicted on Geologic Cross Sections B -B' and E -E' (both east -west, and Maps 8 and 9A, Confidential). Under PR06 -06, only limited main and sub -main development will occur. Given the limited area that will be developed, groundwater inflows are expected to be minimal. Prior to actual mining of this area, inflow modeling will be completed and incorporated into the PAP. WOLF CREEK RESERVE (WCR, Rock -Slope Access and Panels WC -1 through WC -5 initial development, TR13 -83) The WCR underlies portions of the EMD and NMD, and is part of the same water -table groundwater system, so the associated effects of mining on groundwater in this area will be similar to those previously considered and evaluated for the EMD and NMD. (2) The use of approved modeling techniques may be included as part of the permit application, but the same surface and ground water information may be required for each site as when models are not used. � ZIN W 0 Modeling of geologic conditions has been utilized to predict subsidence potential; the results of the modeling are set forth in Exhibit 7, Subsidence Predictions. Overburden stratigraphy, uniaxial compressive strength and tensile strength, angle of draw, caving, and flexure characteristics have been modeled using methods described in the Subsidence Engineer's Handbook (NCB Mining Department, 1975). TR13 -83 2.04 -11 11/03/14