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County Road # 33 • [n reference to Routt County Road 33, TCC plans to install subsidence monuments along the road at the gateroads and center of the panels. These monuments are TCC's typical subsidence monument. The monuments will be monitored on a quarterly frequency while active mining occurs. Once the panel has been mined and two monitoring sessions show no further movement, monitoring will be discontinued and the monuments will be removed. While the road is being undermined, signs will be placed 1,500 feet before entry into the section of road that will be subsided. The signs will be large billboard-type signs, approximately 4' x 8', and lettered with "Begin Subsidence Zone" and "Leaving Subsidence Zone." These signs will be placed so they are visible for each travel direction. In addition to the entrartce signs, warning signs will be placed throughout the subsidence area and will read, "Rough Road, Drive With Care." After subsidence has ended and/or fmal repa'u completed, the signs will be removed from the site. Additionally, during active mining the road will be inspected daily for evidence of surface cracking. The drainage ditches along the side of the road will be checked and repaired as necessary to maintain road drainage. Also, the railroad overpass located in section 28, TSN, R86W, will be monitored when the longwall in panel 6 Right is 2,000 feet from the end of the panel. A monument will be established on the overpass; it will be monitored quarterly and the results submitted in the semi-annual subsidence report. Powerlines Twentymile Coal is not anticipating any material damage resulting from the undermining and subsiding of the • powerlines traversing the Eastern Mining District. The recent experience with undermining and subsiding of the powerlines traversing the southwest mining district substantiates this opinion. The data demonstrates the wood structure, both sign poles and H-structures, were subsided and no loss of service occurred. Public Service has requested that their wooden structure transmission line be monitored. The specifics of the plan are presented later. Havden-Gore Pass Line In reference to the metal structures, the same type of response, as decided above, is anticipated. Hayden-Gore Pass (metal structures) -The metal structures traverse all of the panels located in the Eastern Mining District. The monitoring plan will incorporate both visual inspections of the line and use of surveying equipment to detect movement of the structures. The distance of the active longwall face from the structure will trigger the powerline monitoring. Monitoring, as described below, will begin when the active face is within 500 feet of the structures and intensive monitoring will conclude when the active longwall face is 1,500 feet past the swctures. This process will be repeated for each panel within the Eastern Mining District. Once the active face is within 500 feet of the powerline, daily visual inspections of the powerlines, which includes verifying that the powerline has not come down on the county road or the railroad tracks, will commence and will continue until the face is 1,500 feet past it. The visual inspection will provide a daily log on stability of the powerlines and support structures. During the inspections, the condition of the structure will be observed and changes to the structures will be noted accordingly. This will include notes on integrity of bolts, support structures, insulators, foundation/soil contact areas, etc. These records will be maintained at Twentymile's office. • ~~. - Permit Renewal No. 3 2.05-191.1 12/10/98