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results. Piezometer observations, falling head parameter tests and analytical <br /> projections were completed in order to predict appropriate phreatic surfaces within <br /> the proposed waste structure. Data for the 1992 analysis utilized data collected for <br /> the 1985 analysis. <br /> The applicant has committed to the installation and quarterly monitoring of three sets <br /> of 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 <br /> interval spacing. The operator has also committed to quarterly reporting of visual <br /> inspections of the topsoil, non-toxic soil cover stockpiles, and refuse pile. <br /> For the Lower Permanent Waste Pile, drainage will be controlled by a series of <br /> drainage ditches, terraces, and a sedimentation pond. Since the pile will be <br /> constructed in phases, the drainage system will also be built in phases. All disturbed <br /> area drainage from the topsoil piles, subsoil stockpile and waste pile will be routed <br /> to the sedimentation basin at the northwest comer of the lower waste pile (MB-2R). <br /> The design incorporates several permanent drainage features into the plan. After <br /> final reclamation of the pile, the terraces will be barricaded with rocks or berms to <br /> prevent access to the pile. However, the terraces will still function to control runoff <br /> from the pile. A hundred year diversion ditch has been constructed around the <br /> perimeter of the pile to permanently collect any runoff from the site and safely route <br /> it to the natural drainage system. For a discussion of the hydrologic effects of the <br /> waste pile on both surface and ground water, see the hydrology section in the <br /> Probable Hydrologic Consequences section of this findings document. <br /> The Division has granted a variance from Rule 4.10.4(5), to cover the lower waste <br /> pile with a minimum of four feet of non-toxic and non-combustible material. The <br /> operator was able to demonstrate that there would be no expected detrimental effects <br /> on revegetation and that the probability of spontaneous combustion occurring is very <br /> low with a proposed soil cover of 18 to 24 inches. A satisfactory revegetation, <br /> erosion, and spontaneous combustion monitoring plan was proposed for the lower <br /> waste pile. Also, contingency plans were proposed for all three concerns in the <br /> event of failure or poor reclamation success. Therefore, upon reclamation of the <br /> lower waste pi,,:, the operator will cover the pile with 18 to 24 inches of topsoil and <br /> subsoil. For more information, please see information regarding Technical Revision <br /> No. 53. <br /> The West Elk Mine is permitted to dispose coal mine waste from other neighboring <br /> operations, if comparable in characteristic to MCC's refuse In the past, MCC has <br /> accepted sediment clean-out from the Terror Creek Loadout and development waste <br /> from Bear Coal Company (4.10.1(2)). <br /> The lower refuse pile is inspected quarterly by a qualified professional specialist <br /> under the direction of a professional engineer, experienced in construction of similar <br /> 44 <br />