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During the recent development (late November, December, 1997) of the 6 Right gateroad inflows were <br />encountered from the Wadge Overburden between cross cut 24 to 27. The initial inflow was measured at <br />• approximately 265 to 275 gallons per minute. Maximum inflow rates have leveled off to 65 gallons per minute <br />(2001 & 2002 monitoring). The source of the water is from the roof. No vertical or horizontal offsets were <br />observed; therefore the inflow was not from fault. TCC enlisted the assistance of a consultant (James G. Nalven <br />Consulting) to obtain a better understanding of the reason for the inflow in this area. This is the most water TCC <br />has encountered form a single area since mining was initiated in the eazly 1980's. Mr. Nalven visited the mine site <br />on December 2°d and 3's, 1997, to investigate the source of the inflow. The flow is coming from an area that is <br />coincident with the Foidel Creek lineament or valley. This portion of the 6 Right gate road also has the lowest <br />overburden (350 to 450 feet) to be mined under in the East Mine District. Also, the area is located were the dip is <br />increasing significantly along the steep (8 to 25% grade) western flank of the Twentymile Park Syncline. These <br />three geologic features can increase fracturing of the rock, open joints, and cause movement along bedding planes <br />thus producing increased permeability. In addition to the flow measurements, field EC readings were obtained to <br />provide insight into the source of the water. The EC readings were recorded at 4000 mmhos/cm. This reading <br />corresponds with the EC values obtained from the adjacent and up dip surface mine spoil water. Previously, TCC <br />has experienced spoil water migrating into the underground workings and elevating the EC levels in the Wadge <br />Overburden. This phenomenon has been recorded in the Annual Mine Inflow studies. Presently, the water is being <br />captured at the face and pumped to a "Shark Tank" and them pumped from the section onto an underground sump. <br />During the 1997 roof and floor samples were obtained form drill holes 97-006 and 97-007. The data for drill hole <br />is presented on tables 20D &, E. A review of the data indicates that it all the parameters, except for boron, are <br />within or below the values previously reported by TCC. The boron concentration is relatively low, a1.57 mg/kg, <br />and should not present any environmental problems. It is especially important note that the data is relatively <br />consistent over the entire mine property. This leads one to believe that further roof and floor sampling is not <br />warranted. <br />• NMD (Panels 12 Right through 16 Right) PR 99-OS <br />The genera] geology and hydrology of the segment of the NMD has been described previously in the original <br />Foidel Creek Mine application, and subsequently updated through permit revision 3 and 4. The 1998 drilling <br />program was used to validate the prior description. TCC did not find any unsuspected geologic conditions that <br />would modify the original descriptions. <br />The 97-013 TM/TC monitoring wells, which were installed on the northern side of the property did locate a fault <br />which was previously projected for this area. The fault had an estimated displacement of 200-250 feet, and this <br />will be used to define the mining boundary for the panels in the second north mining district. No major inflows of <br />water were encountered during the drilling of this well. The location of the well is shown on Map 13A. <br />The expansion of the mine into the Northern Mining District will see the continued development of the reserves <br />located in the Twentymile Park Basin. As presented in PR-04, this is an enclosed ground water basin, which is <br />rimmed by the outcrops of the major lithologic units. Those units are described above. <br />The NMD is located more in the heart of the closed ground water basin. TCC continues to have monitoring wells <br />in the Twentymile Sandstone, Wadge Overburden, Trout Creek Sandstone and Alluvial wells in the alluvium of <br />Foidel, Fish, Middle and Trout Creeks. The hydrologic gradients of the bedrock units continues to be toward the <br />center of the basin. The NMD will mine towards the center of the basin and then up dip from it. As in PR-04, the <br />focus of the hydrologic monitoring program for the bedrock units will focus on the Twentymile and Trout Creek <br />Sandstones. <br />• During the development of the Northeast Mains, TCC will be crossing the same fault thaf was first intercepted in <br />10 Right gate road. No significant problems are anticipated while driving through this fault. TCC does not <br />anticipate encountering any significant ground water inflows. <br />As with the 7 Right through 2 Right panels, all of the longwall panels will be to the east of the fault. Only the <br />submaining will be driven in through the fault, thus encountering the mining conditions in NMD. <br />PR 03-06 2.04-16.2 05/07/03 <br />