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EFCI's subsidence monitoring and mitigation plans for the waterline were included <br />in the monitoring, and subsidence control plans. <br />RMG's original description of worst -case subsidence projections indicated that <br />material damage or diminution of reasonable foreseeable use could result from <br />possible mine subsidence within the permit and adjacent areas. Consequently, a <br />subsidence survey and subsidence control plan were prepared for the Southfield <br />mining operations. These plans, originally implemented by Dorchester, were <br />utilized with no significant changes for EFCI's ongoing operations. Now that <br />mining has ceased, subsidence effects have stabilized, and ongoing subsidence <br />monitoring has verified the accuracy of the subsidence projections, regular <br />subsidence monitoring will be discontinued. <br />Subsidence Monitoring Program <br />The purpose of the subsidence monitoring program is to measure surface <br />subsidence and to evaluate the accuracy of subsidence predictions relative to <br />actual ground displacement. The program is designed to yield subsidence data <br />that can be used to evaluate and predict the effects of both development and <br />retreat extraction methods. <br />The subsidence monitoring program developed by RMG in 1983, was prepared in <br />accordance with applicable provisions of Sections 2.05.6 (6) and 4.20 of the <br />Colorado Regulations, and was used by EFCI during the period of active mining. <br />This monitoring program effectively meets the operational and regulatory <br />objectives of subsidence monitoring for the Southfield Mine. Observed <br />subsidence, as documented by historic monitoring results, is comparable to RMG's <br />projections in the initial permit document, therefore, EFCI discontinued regular <br />subsidence monitoring and reporting at the end of 2003. The RMG report and <br />EFCI's supporting monitoring data are included in this section and in Exhibit 23, <br />Subsidence Information. <br />Monitoring is no longer necessary at either the high - resolution ( "South ") <br />subsidence grid or the other subsidence monitoring locations. Subsidence <br />monitoring for the high - resolution grid and the other subsidence monitoring <br />locations, as documented by Semi - Annual Subsidence Reports from 1983 through <br />1995, and 1983 through 2003, respectively, has verified the accuracy of the <br />original subsidence predictions. <br />TR -36 2.05.6 -59 Revised - October 2003 <br />