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EASTERN MINING DISTRICT (Panels 9 Right Through 7 Right) <br />Subsidence Monitoring Plan <br />As in the Southwest Mining District application, TCC did not plan on establishing further subsidence monuments, <br />except as described below. The ongoing subsidence monitoring work has demonstrated that TCC's subsidence <br />predictions were conservative and provided an acceptable description of expected subsidence. Any further <br />subsidence monitoring work would just be further verification of these predictions and is not warranted. <br />County Road # 33 <br />In reference to Routt County Road 33, TCC installed subsidence monuments along the road at the gateroads and <br />center of the panels. These monuments are TCC's typical subsidence monument. The monuments were monitored <br />on a quarterly frequency while active mining occurs. Once the panel was mined and two monitoring sessions show <br />no further movement, monitoring was discontinued and the monuments will be removed. <br />While the road was undermined, signs were placed 1,500 feet before entry into the section of road that was <br />subsided. The signs were large billboard -type signs, approximately 4' x 8', and lettered with "Begin Subsidence <br />Zone" and "Leaving Subsidence Zone." These signs were placed so they were visible for each travel direction. In <br />addition to the entrance signs, warning signs were placed throughout the subsidence area and read, "Rough Road, <br />Drive With Care." After subsidence has ended and/or final repair completed, the signs will <br />be removed from the site. <br />Additionally, during active mining the road was inspected daily for evidence of surface cracking. Visual inspections <br />stopped 30 days after longwall mining was completed, or the face was 1500 feet beyond the subsided point. The <br />drainage ditches along the side of the road were checked and repaired as necessary to maintain road drainage. <br />Also, the railroad overpass located in section 28, TSN, R86W, will be monitored by establishing a monument in the <br />overpass. Likewise a monument will be placed in RCR 27 approximately 2,000 feet west of its intersection with <br />RCR 33. Both of these monuments will be monitored quarterly and the results submitted in the semi - annual <br />subsidence report. <br />Powerlines <br />Twentymile Coal did not see any material damage resulting from the undermining and subsiding of the powerlines <br />traversing the Eastern Mining District. The data demonstrated the wood structure, both sign poles and H- structures, <br />were subsided and no loss of service occurred. Public Service requested that their wooden structure transmission <br />line be monitored. The specifics of the plan are presented later. <br />Permit Renewal No. 3 2.05 -189 1115100 <br />