2011-06-20_PERMIT FILE - C1982056A (5)

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The flow is coming from an area that is coincident with the Foidel Creek lineament or valley. This portion of the 6 -Right gateroad also has the lowest overburden (350 to 450 feet) to be mined under in the East Mine District. Also, the area is located were the dip is increasing significantly along the steep (8 to 25 percent grade) ` • western flank of the Twentymile Park Syncline. These three geologic features can increase fracturing of the rock, open joints, and cause movement along bedding planes thus producing increased permeability. In addition to the flow measurements, field EC readings were obtained to provide insight into the source of the water. The EC readings were recorded at 4,000 mmhos /cm. This reading corresponds with the EC values obtained from the adjacent and up dip surface mine spoil water. Previously, TCC has experienced spoil water migrating into the underground workings and elevating the EC levels in the Wadge Overburden. This phenomenon has been recorded in the Annual Mine Inflow studies. Presently, the water is being captured at the face and pumped to a "Shark Tank" and then pumped from the section onto an underground sump. During the 1997 roof and floor samples were obtained from Drillholes 97 -006 and 97 -007. The data for drillholes is presented on Tables 20D and E. A review of the data indicates that it all the parameters, except for boron, are within or below the values previously reported by TCC. The boron concentration is relatively low, al.57 mg/kg, and should not present any environmental problems. It is especially important note that the data is relatively consistent over the entire mine property. This leads one to believe that further roof and floor sampling is not warranted. NMD (Panels 12 -Right through 16- Right, PR99 -05) The general geology and hydrology of the segment of the NMD has been described previously in the original Foidel Creek Mine application, and subsequently updated through Permit Revisions 3 and 4. The 1998 drilling program was used to validate the prior description. TCC did not find any unsuspected geologic conditions that would modify the original descriptions. The 97 -013 TM/TC monitoring wells, which were installed on the northern side of the property, did locate a • fault which was previously projected for this area. The fault had an estimated displacement of 200 -250 feet, and this will be used to define the mining boundary for the panels in the second North Mining District. No major inflows of water were encountered during the drilling of this well. The location of the well is shown on Map 13A. The expansion of the mine into the Northern Mining District will see the continued development of the reserves located in the Twentymile Park Basin. As presented in PR -04, this is an enclosed ground water basin, which is rimmed by the outcrops of the major lithologic units. Those units are described above. The NMD is located more in the heart of the closed ground 'water basin. TCC continues to have monitoring wells in the Twentymile Sandstone, Wadge Overburden, Trout Creek Sandstone and Alluvial wells in the alluvium of Foidel, Fish, Middle and Trout Creeks. The hydrologic gradients of the bedrock units continue to be toward the center of the basin. The NMD will mine towards the center of the basin and then updip. As in PR -04, the focus of the hydrologic monitoring program for the bedrock units will focus on the Twentymile and Trout Creek Sandstones. During development of the Northeast Mains, TCC will be crossing the same fault that was first intercepted in the 10 -Right gateroad. No significant problems are anticipated while driving through this fault. TCC does not anticipate encountering any significant ground water inflows. As with the 7 -Right through 2 -Right panels, all of the Iongwall panels will be to the east of the fault. Only the sub - mains will be driven in through the fault, thus encountering the mining conditions in NMD. Roof, floor and coal samples were obtained from holes 97006 and 97007. The data is presented on Tables 20D, 20E and 20F. 0 PR06 -07 2.04 -16.2 11/07/06