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

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EMD and Southern Portion of WCR (ENID Panels 2 -Right through 9- Right, PR97 -04, TR13 -83) The geology for the EMD is the same as that presented in Permit Revision No. 93 -03. However, Table 6B, 1997 PR 97 -04 Federal Reserve Calculations for the Eastern and Northern Mining Districts, which is considered to be confidential, presents the federal reserves that will be mined in the remainder of the Eastern Mining District and the Northern Mining District. The detailed Wadge Seam structure is shown on Map 6, Wadge Seam Structures. The geochemical data presented for PR 93 -03 is used for this revision as well. Geologic and geochemical data for the Wolf Creek Seam are provided in Exhibit 53, Wolf Creek Reserve Geologic and Mine Plan Information. The general geology and hydrology of the EMD has been described in previous permitting actions, i.e. original application and updated with PR -3. During 1997, a drilling program was conducted to further define the geologic setting in the remainder of the EMD. During this program particular attention was given to defining the Wadge Seam parting that defines the southern limit of the EMD. Drillholes 97 -001 and 97 -003 were used to define the southern mining limit. Both of these holes showed an in -seam parting of 1.9 - 2.5 feet and thinning of the seam. The overlying stratigraphy is the same as previously discussed. This information was used to finalize the mine plan as presented on Map 23. Drill Site 97 -011, which was designed for multiple holes, was used to provide a better understanding of the fault as it occurs in the Northeast sub - mains. Three borings were advanced at this location to determine the location and magnitude of the fault. This was done by advancing two borings on the east side of the fault, with each boring intersecting the fault. Another boring was advanced on the west side of the fault into and through the coal seam. A deviation log was run in each of the holes to allow for accurate placement of end -point of boring. This data, along with the other geophysical information, was used to correlate depth and seam thickness between each boring. After the data was processed, the TCC Geologist was able to provide a better definition of the fault through the sub - mains, which was then used to prepare a cut sequence through this area. The expansion of the mine into the remainder of the EMD resulted in continued development of the Wadge Seam reserves located in the Twentymile Park Basin. As discussed previously, this is an enclosed ground water basin which is rimmed by outcrops of the major lithologic units. The units within this area include the Fish Creek Sandstone (a local sandstone unit), Twentymile Sandstone, Marine shale, Wadge overburden (which includes the Wadge seam),Wadge /Wolf Creek Interburden, Wolf Creek Seam, Wolf Creek Underburden, and the Trout Creek Sandstone (which is a marker bed for TC). TC has not seen any deviation in the vertical orientation of these units over the entire property, except for localized displacements caused by faults. As indicated, the Foidel Creek Mine operates within a closed ground water basin. TC has completed monitoring wells in the following formations within this basin: Twentymile Sandstone, Wadge Overburden, Wolf Creek Interburden/Coal unit, Trout Creek Sandstone, and alluvial wells in the alluvium of Foidel, Fish, Middle, and Trout creeks. The hydrologic gradients for all units are oriented towards the center (axis) of the basin. The EMD was mined from south to north toward the center of the basin and immediately east of the major faults. As TC continues mining, the focus of the hydrologic monitoring program will be on the Twentymile and Trout Creek Sandstones. The EMD fault was first encountered in the 10 -Right gate -road and had a displacement of 22 to 23 feet, in the 9 right gate -road the fault had a displacement of 13 to 15.5 feet, in the 8 -Right gate -road the fault had a displacement of 8 to 15 feet, in the 7 -Right gate -road the fault had a displacement of 8 to 10 feet and in the 6 Right gate -road the fault had a displacement of 13 feet. The faults were relatively dry when encountered and did not yield significant flows to the mine, as documented by the Annual Inflow reports filed with the CDRMS. TC mined through the fault and the steep grade zone in the 9 -Right and 8 -Right longwall panels. Given very difficult mining conditions in this area, TC made the decision to modify the mine plans to avoid mining through the fault and up the steep grade in longwall panels 7 -Right through 2 -Right During the development of the 6 -Right gate -road, inflows were encountered from the Wadge Overburden between crosscuts 24 to 27. The initial inflow was measured at approximately 265 to 275 gallons per minute. Maximum TR13 -83 2.04 -16.1 11/03/14