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The West Elk Mine is currently permitted for three refuse disposal areas - the Refuse <br />Pile Expansion Area, the Upper Refuse Pile and the Lower Refuse Disposal Area. The <br />upper pile has not been constructed and is on indefinite hold. Specific information on <br />that waste pile can be found in Exhibit 50 of the permit application package. The lower <br />refuse pile and refuse pile expansion are both in use. Specifics regarding these piles are <br />located in Exhibits 51 and 70 respectively. <br />The lower waste pile is located adjacent to Highway 133, at the west side of the mouth <br />of Sylvester Gulch. MCC initially proposed the disposal of waste rock within two waste <br />piles in the original permit application. One pile, the "initial waste rock pile," would <br />contain approximately 1.25 million cubic yards and would be located on the lower <br />facilities bench (the current location of the shop). Subsequent to permit approval, this <br />initial waste rock pile was deleted from MCC's permit. <br />In the summer of 1985, Mountain Coal Company submitted an application for Permit <br />Revision 3 requesting approval of a permanent lower waste pile to be located adjoining <br />the mouth of Sylvester Gulch. This application originally requested approval to <br />permanently dispose of 1.77 million tons of coal processing waste within the proposed <br />structure. The original design phased the refuse pile into five specific design layouts <br />(Phases I through V), including recompaction and reconfiguration of temporarily stored <br />waste material. The pile was constructed according to this original phased design until <br />the Phase IV configuration. TR-63 was submitted in November 1992, which eliminated <br />Phase V and reduced the pile to 1.2 million tons. The proposed storage volume <br />represents a 15.7 year life. The proposal included the combination of a 28,500 cubic <br />yard topsoil pile during Phases I through III and a maximum of 45,000 cubic yards of <br />non-toxic soil cover (subsoil) stockpile. Topsoil removed for Phase IV will be stored on <br />the 50-foot bench constructed in Phase III. In addition, an access road was constructed <br />in Phase Three and a portion of the Sylvester Gulch access road to the main fan portal <br />was relocated. Underdrains have been constructed beneath the pile. Piezometric <br />groundwater monitoring will be conducted. Slopes of the pile will be maintained at <br />2.5H:IV. <br />The TR-63 application included a thorough slope stability analysis performed in <br />accordance with the prudent state-of-the-art slope analysis for the original design in <br />1985, and for the redesigned pile in 1992. Material strength values were derived from <br />on-site sample testing and nearby previously reported test results. Piezometer <br />observations, falling head parameter tests and analytical projections were completed in <br />order to predict appropriate phreatic surfaces within the proposed waste structure. Data <br />for the 1992 analysis utilized data collected for the 1985 analysis. <br />The applicant has committed to the installation and quarterly monitoring of three sets of <br />survey monuments to monitor slope stability of the waste structure. One row of <br />monuments has been installed parallel to the state highway adjoining the toe of the <br />waste pile on 100-foot intervals. Two additional rows of monuments have been <br />installed perpendicular to the highway on the facial slope of the pile at 50-foot interval <br />spacing. The operator has also committed to quarterly reporting of visual inspections of <br />the topsoil, non-toxic soil cover stockpiles, and refuse pile. <br />41