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is the only party with a water supply well completed in the Trout Creek Sandstone in the vicinity of the Eastern Mining District. .Roads There are several ranch roads that traverse the longwall panels and these roads will be subsided. These roads are used by local or surface owners and access to these roads is limited to those specific owners. No significant impact to the roads should result from TCC's mining activities. No control plan is contemplated for these roads. County Road 33 TCC plans to subside Routt County Road 33, which is a two-lane asphalt road; (refer to Map 23B, Structures and Renewable Resources, for location). Panels 5 Right and 6 Right undermine and subside the road in the next 6ve- yearpermit term(1998-2003). Twentymile has undermined and subsided Routt County Road 33 where it overlies panel 9 Right. TCC monitored the road while mining and subsidence was occurring and no significant impacts to the road resulted from this activity. The road responded the same way when it is subsided during the mining of panels 5 Right and 6 Right. A control plan has been developed for the road and is presented in a later section. Powerlines Three different powerlines traverse panels 2 Right through 6 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, and 3) 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 aze shown on Map 23B, Structures and Renewable Resources ~n reference to the jointly owned line where it traverses sections 21, 27, and 28, Twentymile has the right to ndermine 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 interruption. The tilting could result from the differential settling that may occur in relation to the four legs of the tower. 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. TCC subsided all these lines while mining panels 9 Right, 8 Right, and 5 Right without any significant impacts to the lines. U 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. These structures were subsided duringthe mining of Qanel 9 Right without any significant impacts. The YVEA powerline traverses panels 6 Right and 5 Right. The powerline was undermined and subsided as .ongwall mining progressed through these panels. TCC's experience with this type of powerline in the Southwest PerrnitRenewalNo.3 2.05-181.2 APPRO~J~D APR 2 4 2b®0o6/00