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County Road 33 <br />~CC subsided County Road 33, wfiich is a two lane asphalt road (refer to Map 23B, Structure and Renewable <br />Resources) when Panels 9 Right, 8 Right, 7 Right, 6 Right, and 5 Right were longwall mined. 9 Right undermined <br />the road during the period of May, 1996 -July, 1996. The 8 Right Panel undermined the road during the period <br />April 1997 -May 1997. The 7 Right Panel undermined the road in February 1998. The 6 Right Panel undermined <br />the road in August, 1998, and then again during the period November 1998 -December 1998. The time variation <br />for the 6 Right Panel was due to the fact that the road entered and ]eft the panel in two distinct locations. The 5 <br />Right Panel undermined the road during March 1999 -May 1999. The subsidence which resulted was within the <br />projections TCC provided in Exhibit 7E, Predictions of Subsidence Eastern Expansion of Foidel Creek Mine. <br />Powerlines <br />Four different powerlines traverse panels 8 Right and 9 Right. The owners and construction of the lines are as <br />follows: 1) Public Service Company -wooden H-structure (Wolcott Tap-Wolcott), 2) Western Area Power <br />Administration -wooden H-structure, 3) Yampa Valley Electric Association -single wooden pole stmcture, and 4) <br />joint ownership by Public Service Company, Tri-State Generation & Transmission, Western Area Power <br />Association, and Platte River Power Administration -metal structure (Hayden-Gore Pass line). The location of the <br />powerlines are shown on Map 23B, Structures and Renewable Resources <br />fr reference to the jointly owned line where it traverses sections 21, 27, and 28, TCC has the right to undermine and <br />subside the powerline. This right is described in the easement between Tri-State and Getty Minerals Marketing, <br />Inc., to which our respective companies have succeeded, and is recorded with the Routt County Clerk and Recorder <br />in Book 607, at Page 1642. The worst possible consequences of subsidence could result in the metal structures <br />tilting and deforming, and/or the powerline becoming detached from the tower, which could result in power <br />nterruption. The tilting could result from the differential settling that may occur in relation to the four legs of the <br />~wer. The differential settling occurs due to the location of the legs in relation to the advancing subsidence trough. <br />Along with the differential settling, additional strain could be placed on foundations leading to cracking of the <br />cement. <br />Another worst-possible-case consequence for the powerline would result if the line separated from the tower <br />connectors and fell to the ground. If this occurred, and either a train or a car were traveling under the line, there <br />could be contact between the line and vehicle. <br />In reference to the two wooden H-structures, the worst possible consequences of subsidence would result in the <br />tilting of the structures. TCC has undermined and subsided these types of structures in the Southwest Mining <br />District and observed the tilting of the poles. The integrity of the poles remained intact and they continue to <br />function with no loss of service. TCC is anticipating the same type of response for the wooden structures located in <br />the Eastern Mining District. The Public Service Company line, which is one of the wooden structures, has a gang <br />switch located within the subsided area and has indicated that tilting of the switch could result in a malfunction. <br />The YVEA powerline traverses panels 9 Right, 8 Right, and 7 Right located in Section 23, TSN, R86W. The <br />powerline will be undermined and subsided as longwall mining progresses through these panels. TCC's experience <br />with this type of powerline in the Southwest Mining District indicates that no problems or material damage will <br />occur to the line due to subsidence. <br />u <br />E1PPR®1/ED APR 2 4 2000 <br />Permit Renewal No. 3 2.05-179 2/2/00 <br />