|
These facilities are shown on Maps 24, Surface Facilities and Freshwater Systems, and 26, Fish Creek Borehole
<br />Area Facilities and Access Road. Surface disturbances are discussed under the response to 2.05.3(3) below. Given
<br />} the long history of mining on the site, disturbance boundaries are marked by a variety of markers including steel
<br />fence-posts, surveyor markers, fiberglass or steel roof bolts, and steel rebar, all of which are identifiable by their
<br />orange color or by orange paint on the top one-foot of the marker.
<br />Production of coal began from the portal slopes. A set of entries were driven toward the north (ls` North Mains).
<br />The 15` and 2nd North Mains were developed approximately 8,000 feet to the north. Once this initial development
<br />was completed, the North Mains were angled to the west and driven to, what was then the northern permit
<br />boundary. At a point approximately 1,850 feet north of the portals, a new set of mains (ls` Main West) was turned
<br />to the west and developed approximately 4,700 feet. Approximately 500 feet to the north of the 15Y Main West a
<br />second set of mains was driven approximately 2,700 feet to the west. In the initia12,700 feet, these mains typically
<br />consist of six parallel entries. Depending on conditions, the number of entries may vary, up to a maximum of
<br />seven. Once development progressed to this point, the 6-7 entries were necked down to a three-entry gate-road
<br />system for the remainder of each panel.
<br />A set of sub-mains were driven from 1 S` Left heading, extending approximately 3,000 feet to the south. These sub-
<br />mains consist of five entries, and the gate-roads for Panels 7 through 9 were developed from the sub-mains to the
<br />west. These sub-mains are shown as the 1 S` South Sub-mains on Map 23. The first set of six longwall panels were
<br />developed to the west from ls` North Mains. These panels extended until they reached either of two projected faults
<br />or until the 25 degree angle-of--draw line from the panel reached the buffer zone for Fish Creek, whichever came first.
<br />An estimated 12.3 million tons of coal were recovered from this first block of longwall panels.
<br />In order to explore and assess the fault zone on the west end of the panels, TCC extended the 1 S`, 2nd and 3rd Left
<br />entries beneath the Fish Creek AVF. These entry extensions were similar in nature to the previously approved 2nd
<br />West Main entries, which were identified in the 1986 Findings of Compliance Document as having no potential
<br />adverse impacts upon the AVF. This determination was further supported by a Wilson Pillar Stability Analysis
<br />which yielded a safety factor of 2.2 for the anticipated 35x 80 foot pillar design of the proposed extensions. Based
<br />on available hydrologic baseline data, TCC did not anticipate any major ground water inflows during the proposed
<br />extensions, and none were encountered. TCC also partially extended Panels 5 and 6 beneath the designated Fish
<br />Creek AVF. While this extension was not contemplated in the original Foidel Creek mine plan, mining experience
<br />indicated that subsidence associated with longwall extraction beneath the designated AVF area would not result in
<br />significant surface impacts. In order to objectively assess potential impacts on the designated AVF due to proposed
<br />panel extension, TCC completed subsidence projections and evaluated related effects. The subsidence projections
<br />were based on existing available subsidence data for TCC's ongoing longwall operations, and reflect an increase in
<br />panel width for Pane16, from 625 feet (current panel width) to 850 feet. The subsidence projections and evaluation
<br />of potential related effects on the designated Fish Creek AVF are documented in Exhibits 7B, 7C, 45, and 46.
<br />During initial mining of Panel 6, Well GWB-2 was subsided, as predicted, and the well was damaged and
<br />subsequently replaced. A replacement well (GWB-2R) was installed adjacent to the existing well. Well GWB-2R
<br />was constructed adjacent to the existing well as a two-inch well with Schedule 80 PVC. The well completion
<br />report was forwarded to the CMLRD. The two wells were monitored for water levels twice per week for atwo-
<br />week period, thereafter, only Well GWB-2R is monitored per the schedule presented on Table C of Exhibit 14.
<br />Well GWB-2 was sealed with Volclay and permanently abandoned. Prior to permanently abandoning well GWB-2,
<br />the CMLRD inspected the well and approved well abandonment.
<br />Originally, it was anticipated that room and pillar mining would be required to augment longwall production.
<br />Given, however, the productivity, efficiency, and increased recovery with the longwall mining system, preliminary
<br />plans to develop a room and pillar area on the east side of the North Mains were abandoned. As shown on Maps
<br />23, and 23A, additional longwall panels were planned and developed to the east of the North Mains in the Eastern
<br />Mining District. Panels 3-Right through 10-Right were developed and mined in the Eastern Mining District.
<br />- During mining of these panels, a small segment of Middle Creek (extreme eastern end of Panels 3-Right through 7-
<br />Right), aportion of Foidel Creek (Panels 8-Right through 10-Right), County Road 33 (Panels 8-Right through 10-
<br />TR08-64 2.05-12 06/17/08
<br />
|