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Surface Mining Near Underground Mining <br />While there are a number of surface mines in the general vicinity of the mine <br />area, all of these mines are inactive, all except the GEC Pit are located well above <br />(three to four hundred feet) the interval to be mined, and none are within angle <br />of draw limits or within four hundred feet of the ultimate limits of underground <br />mine workings. Consequently, the provisions of this section are not applicable. <br />Subsidence Survey, Subsidence Monitoring, and Subsidence Control Plan <br />The Subsidence Survey, Subsidence Monitoring and Subsidence Control Plan <br />prepared by Rocky Mountain Geotechnical (RMG) for Dorchester Coal in 1983, <br />addresses all applicable regulatory requirements and has been utilized as the <br />subsidence plan for EFCI since acquisition of the mine from Dorchester in 1985. <br />The RMG subsidence plan and supporting monitoring data is contained in Exhibit <br />23, Subsidence Information. Since measured subsidence over the past eighteen <br />years is well within the range predicted by RMG in the original mine permit and <br />progressive subsidence has effectively ceased, EFCI proposed and the CDMG <br />approved elimination of quarterly and semi-annual subsidence monitoring and <br />reporting at the end of 2003. In order to confirm and document long-term <br />surface subsidence effects, EFCI will conduct two additional subsidence surveys <br />during years 3 and 9 (2006 and 2012) of the reclamation liability period. These <br />final surveys will be documented by subsidence monitoring reports submitted to <br />the CDMG. Changes to the monitoring plan are discussed in the following <br />sections. <br />Inventory of Structures and Renewable Resource Lands. As part of the <br />subsidence plan, an inventory of structures and renewable resource lands was <br />conducted for those areas that have been or will be undermined by either <br />Dorchester or subsequent EFCI operations. An itemized list of potentially affected <br />structures is as follows: <br />• The Thompson Ranch Buildings (2 houses and barn) <br />• County Road 92 <br />• County Road 15 <br />• Refuse Disposal Area <br />TR-36 2.05.6-55 Revised -October 2003 <br />