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EMD and Southern Portion of WCR (EMD Panels 2RT through 9RT, and WCR Panel WC-4RT, PR97-04,
<br />PR15-11, TR13-83)
<br />The geology for the EMD is the same as that presented in Permit Revision No. 93-03. However, Table 6B, 1997
<br />PR 97-04 Federal Reserve Calculations for the Eastern and Northern Mining Districts, which is considered to be
<br />confidential, presents the federal reserves that will be mined in the remainder of the Eastern Mining District and the
<br />Northern Mining District. The detailed Wadge Seam structure is shown on Map 6, Wadge Seam Structures. The
<br />geochemical data presented for PR 93-03 is used for this revision as well. Geologic and geochemical data for the
<br />Wolf Creek Seam are provided in Exhibit 53, Wolf Creek Reserve Geologic and Mine Plan Information.
<br />The general geology and hydrology of the EMD has been described in previous permitting actions, i.e. original
<br />application and updated with PR -3. During 1997, a drilling program was conducted to further define the geologic
<br />setting in the remainder of the EMD. During this program particular attention was given to defining the Wadge
<br />Seam parting that defines the southern limit of the EMD. Drillholes 97-001 and 97-003 were used to define the
<br />southern mining limit. Both of these holes showed an in -seam parting of 1.9 - 2.5 feet and thinning of the seam.
<br />The overlying stratigraphy is the same as previously discussed. This information was used to finalize the mine plan
<br />as presented on Maps 23 and 23 WC.
<br />Drill Site 97-011, which was designed for multiple holes, was used to provide a better understanding of the fault as
<br />it occurs in the Northeast sub -mains. Three borings were advanced at this location to determine the location and
<br />magnitude of the fault. This was done by advancing two borings on the east side of the fault, with each boring
<br />intersecting the fault. Another boring was advanced on the west side of the fault into and through the coal seam. A
<br />deviation log was run in each of the holes to allow for accurate placement of end-point of boring. This data, along
<br />with the other geophysical information, was used to correlate depth and seam thickness between each boring. After
<br />the data was processed, the TCC Geologist was able to provide a better definition of the fault through the sub -
<br />mains, which was then used to prepare a cut sequence through this area.
<br />The expansion of the mine into the remainder of the EMD resulted in continued development of the Wadge Seam
<br />reserves located in the Twentymile Park Basin. As discussed previously, this is an enclosed ground water basin
<br />which is rimmed by outcrops of the major lithologic units. The units within this area include the Fish Creek
<br />Sandstone (a local sandstone unit), Twentymile Sandstone, Marine shale, Wadge overburden (which includes the
<br />Wadge seam, Wadge/Wolf Creek interburden, and Wolf Creek seam), and the Trout Creek Sandstone (which is a
<br />marker bed for TC). TC has not seen any deviation in the vertical orientation of these units over the entire property,
<br />except for localized displacements caused by faults.
<br />As indicated, the Foidel Creek Mine operates within a closed ground water basin. TC has completed monitoring
<br />well- in the following formations within this basin: Twentymile Sandstone, Wadge Overburden (and associated
<br />units), Trout Creek Sandstone, and alluvial wells in the alluvium of Foidel, Fish, Middle, and Trout creeks. The
<br />hydrologic gradients for all units are oriented towards the center (axis) of the basin. The EMD was mined from
<br />south to north toward the the center of the basin and immediately east of the major faults. As TC continues mining,
<br />the focus of the hydrologic monitoring program will be on the Twentymile and Trout Creek Sandstones.
<br />The EMD fault was first encountered in the l0 -Right gate -road and had a displacement of 22 to 23 feet, in the 9
<br />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
<br />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
<br />f9111t had a displacement of 13 feet. The faults were relatively dry when encountered and did not yield significant
<br />flows to the mine. as documented by the Annual Inflow reports tiled with the CDIUvIS.
<br />ice. ,....,:..a �,a va..�l. ..,,.J If—u— �:.i.0 :, v ., �li'v1.i Si ci.d- i.l�r.�. iii �1i i-i�i�i�t ailu u-R1511L lvii,4vvriii i)aii jl 61vGrh vCt�r
<br />difficult mining conditions in this area, TC made the decision to modify the mine plans to avoid mining through the
<br />fault and up the steep grade in longwall panels 7 -Right through 2 -Right
<br />During the development of the 6 -Right gate -road inflows were encountered from the Wadge Overburden between
<br />crosscuts 24 to 27. The initial inflow was measured at approximately 265 to 275 gallons per minute. Maximum
<br />PRI, 5-11 2.04-16.1 07/06/1.5
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