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• Subsidence Surveys <br />Stipulation 12 requires that five subsidence monitoring stations in Jerry Creek Canyon <br />and Coal Canyon be surveyed to detect movement or change in elevation. Two surveys were <br />conducted during 2000. Table 1 shows the results of the surveys conducted since 1996. <br />These results indicate no subsidence at any of the measured locations. <br />TABLE 1 -SUBSIDENCE MONITORING SURVEY DATA COMPARISON <br />• <br /> SUBSIDENCE MONUMENT ELEVATIONS <br />Date SM01 SM02 SM03 SM04 SM05 <br />Fa111996 4869 .36 4898. 68 4970 .44 4985. 68 5121 .62 <br />04/17/97 4869 .30 4898. 53 4870. 47 4985. 74 5121 .65 <br />12/18/97 4869 .45 4898. 71 <br />10/05/98 4869 .24 4898. 56 4970. 27 4985. 72 5121 .55 <br />12/15/98 4869. 23 4898. 56 4970. 27 4985. 72 5121 .55 <br />08/30/99 4869. 54 4898. 90 4970. 65 4986. 11 5121 .81 <br />11/23/99 4869. 41 4898. 81 4970. 14 4985. 97 5121 .74 <br />4/24/00 4869. 45 4898. 84 4970. 50 4986. 04 5121 .75 <br />9/11/00 4869. 45 4898. 85 4970. 53 4986. 04 5121 .74 <br />Minimizing Subsidence <br />Both the Roadside North Portal Mine and the Roadside South Portal Mine are currently <br />• <br />idle with no immediate plans for continued operations. <br />Conclusion <br />There is no evidence of subsidence related damage caused by the mining operation in <br />the last year. No dangerous subsidence related features were located during the surface <br />investigation or survey of the subsidence monuments. The operator was not notified that <br />subsidence has affected any structures, water supplies or environmentally sensitive areas. <br />2000 Subsidence Report <br />Page 3 <br />