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RCR33 - There are a number of features that will be monitored on RCR33, including: The Foidel Creek culvert
<br />under the road, slope above the road, surface of the road, and monuments in the road and shoulder. Each is
<br />discussed, as follows.
<br />The culvert will be visually inspected on a weekly basis when the longwall face is within 500 feet of the culvert
<br />and continue until the face has progressed 1,500 feet past the culvert. After that, the culvert will be inspected
<br />visually on a monthly basis for three months, and then monitoring will cease. Any repairs will be completed, as
<br />required. Monitoring will focus on condition of the culvert, fill over the culvert, and inlet and outlets. This will
<br />assure the continued useful function of the culvert. The slope above the road, which is subject to the mitigation
<br />work (i.e. stabilizing rocks in source zone), will be inspected visually on a daily basis when the longwall starts in
<br />the 12 -Right Panel and will continue until it progresses 1,500 feet past the zone. Once this occurs, visual
<br />monitoring will cease. When the 13 -Right Longwall Panel starts, the slope will be inspected visually on a daily
<br />basis until it progresses 1,500 feet past the zone.
<br />In addition to visual monitoring, TCC will install subsidence monuments in the shoulder of the road over the
<br />start room, 11 -Right gateroad, and at the point where the road is closest to the centerline of the 12 -Right Panel.
<br />These monuments will be monitored before mining starts, to define the premining elevation, and then quarterly
<br />once mining commences. The monuments will be monitored on a quarterly frequency until mining has
<br />progressed halfway through the 14 -Right longwall panel. Once the longwall has reached this point, the
<br />monitoring will cease and TCC can remove the monuments. Also, TCC will install nail monuments along the
<br />centerline of the road from a point approximately 500 feet south of the 11 -Right gateroad, to a point
<br />approximately 500 feet east of the bleeder entry on the east side of the 12 -Right Panel. These monuments will
<br />be surveyed prior to longwall mining in the 12 -Right panel and then weekly once mining begins in the panel.
<br />The longwall face must be within 500 feet of a nail monument before it is monitored. Monitoring of these
<br />points will cease once the longwall face is 1,500 feet past the nail monument. This same monitoring process
<br />will be done for longwall panels 13 and 14- Right.
<br />NMD and WMD (Panels 17- through 25 -Right and Panels 12- through 17 -Left; PR 03 -06, PR06 -07, and
<br />PR09 -08)
<br />As was proposed in the EMD application (PR97 -04), TCC is not planning on establishing further subsidence
<br />monuments except as described below. Historical and ongoing subsidence monitoring has demonstrated that
<br />TCC's subsidence predictions were conservative, and provided reasonable and accurate projections of
<br />anticipated subsidence and related subsidence effects. Further subsidence monitoring work would not serve a
<br />useful purpose other than further verification of subsidence predictions, and is not warranted. It should be noted
<br />that mining - related subsidence is not expected to impact the proposed 6MN Reservoir, since the Reservoir is
<br />entirely outside of the projected subsidence limits. As an MSHA impoundment, however, the Reservoir will be
<br />inspected on a monthly basis, except during the winter months, to assess the condition of the impoundment, and
<br />specifically, the embankment structure.
<br />RCR27 — TCC will visually monitor affected portions of RCR27 on a dialy basis, beginning when the longwall
<br />face is within 500 feet of the near -edge of the road and continuing until the logwall face is 1,500 feet beyond the
<br />far edge of the road. Visual monitoring will focus on identifying any cracks or differential settling of the paved
<br />road surface, road -bed, or shoulders, any evidence of instability in adjacent road cut - slopes, and any subsidence -
<br />related drainage issues. TCC will also install nail monuments along the centerline of the road from a point
<br />approximately 500 feet south of the 12 -Left gateroad, to a point approximately 500 feet north of the 18 -Left
<br />gateroad. These monuments will be surveyed prior to initiation of longwall mining in the 17 -Left Panel to
<br />establish a baseline, and then weekly once the lonwall face is within 500 feet of a nail monument. Monitoring of
<br />these points will continue until the longwall face is 1,500 feet past the nail monument.
<br />Powerlines - Two powerlines owned by Western Area Power Administration (WAPA), Tri State, and Public
<br />Service Company (PSC), traverse the 19 -Right Panel, as shown on Map 2313, Structures and Renewable
<br />Resources. Details of the monitoring plan for the powerlines overlying the 19 -Right Panel have been developed
<br />in consultation with the utilities. The plan entails visual inspections of the towers and foundations on a periodic
<br />basis, supplemented with surveying as described in the following paragraphs. The affected structures will also
<br />PR09 -08 2.05 -191.5 04/29/09
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