2013-10-17_PERMIT FILE - C1982056A (4)

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County Road 33 XC subsided County Road 33, which is a two lane asphalt road (refer to Map 23B, Structure and Renewable Resources) when Panels 9 Right, 8 Right, 7 Right, 6 Right, and 5 Right were longwall mined. 9 Right undermined the road during the period of May, 1996 — July, 1996. The 8 Right Panel undermined the road during the period April 1997 — May 1997. The 7 Right Panel undermined the road in February 1998. The 6 Right Panel undermined the road in August, 1998, and then again during the period November 1998 — December 1998. The time variation for the 6 Right Panel was due to the fact that the road entered and left the panel in two distinct locations. The 5 Right Panel undermined the road during March 1999 — May 1999. The subsidence which resulted was within the projections TCC provided in Exhibit 7E, Predictions of Subsidence Eastern Expansion of Foidel Creek Mine. Powerlines Four different powerlines traverse panels 8 Right and 9 Right. The owners and construction of the lines are as follows: 1) Public Service Company - wooden H- structure (Wolcott Tap - Wolcott), 2) Western Area Power Administration - wooden H- structure, 3) Yampa Valley Electric Association - single wooden pole structure, and 4) joint ownership by Public Service Company, Tri -State Generation & Transmission, Western Area Power Association, and Platte River Power Administration - metal structure (Hayden -Gore Pass line). The location of the powerlines are shown on Map 23B, Structures and Renewable Resources In reference to the jointly owned line where it traverses sections 21, 27, and 28, TCC has the right to undermine and subside the powerline. This right is described in the easement between Tri -State and Getty Minerals Marketing, Inc., to which our respective companies have succeeded, and is recorded with the Routt County Clerk and Recorder in Book 607, at Page 1642. The worst possible consequences of subsidence could result in the metal structures tilting and deforming, and/or the powerline becoming detached from the tower, which could result in power ;nterruption. The tilting could result from the differential settling that may occur in relation to the four legs of the )wer. The differential settling occurs due to the location of the legs in relation to the advancing subsidence trough. Along with the differential settling, additional strain could be placed on foundations leading to cracking of the cement. Another worst - possible -case consequence for the powerline would result if the line separated from the tower connectors and fell to the ground. If this occurred, and either a train or a car were traveling under the line, there could be contact between the line and vehicle. In reference to the two wooden H- structures, the worst possible consequences of subsidence would result in the tilting of the structures. TCC has undermined and subsided these types of structures in the Southwest Mining District and observed the tilting of the poles. The integrity of the poles remained intact and they continue to function with no loss of service. TCC is anticipating the same type of response for the wooden structures located in the Eastern Mining District. The Public Service Company line, which is one of the wooden structures, has a gang switch located within the subsided area and has indicated that tilting of the switch could result in a malfunction. The YVEA powerline traverses panels 9 Right, 8 Right, and 7 Right located in Section 23, T5N, R86W. The powerline will be undermined and subsided as longwall mining progresses through these panels. TCC's experience with this type of powerline in the Southwest Mining District indicates that no problems or material damage will occur to the line due to subsidence. APPROVED APR 2 4 2000 Permit Renewal No. 3 2.05 -179 2/2/00