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-1•~' 4. Miscellaneous - This section should include such items as portal sealing, powerline removal, culvert removal, etc. Portal Seals - Rule 2.05.4(2 The applicant presents a relatively standard portal sealing plan for the proposed Bear b3 mine; however this sealing plan does not adequately address the potential for gravity discharge of water or discharges containing acid or toxic-producing elements which could occur due to the up-dip nature of the mining operation. The application on page 2.05-28 states that "there has never been any gravity discharge of water from the previous mining operations" and that "no acid-producing or toxic- producing elements are found in the coal seam". This present situation may not be representative of future conditions which may develop during the permit term as the mining operation progresses southward into the C-seam. As such, the applicant must develop portal sealing plans and specifications showing how mine openings will be sealed to prevent uncontrolled mine discharges upon completion of mining. These plans should address two potential discharge conditions, one for non-toxic discharges and one for discharges containing toxic or acid-producing elements. Backfilling and Grading - Rule 2.05.9(2)(c) The application submitted by Bear Coal Company for the proposed Bear No. 3 mine does not adequately address the regulations of the Colorado permanent regulatory program concerning the requirements for backfilling and grading. Specifically, the plan presented in the application does not discuss in adequate detail the stability of the proposed reclaimed configuration in light of the geologic hazards known to exist within and adjacent to the surface facilities and lease area. The Colorado Geological Survey (Rahe Jange, et. al.) has mapped the Somerset yuarlranglc and fi.vc adjoining quadrangles to delineate areas of geologic hazard that could cause an economic loss or affect the safety of the citizens of Colorado. Mapping of the Somerset quadrangle shows that a significant slope failure complex exists within and adjacent to the area of the portal bench, bench access road, and the entire northern quarter of tlrc lease area to an elevation of approximately 6,800 feet. In addition, a localized recent landslide scarp has been delineated directly above the old Clark Mine portal entry. In light of these known potential geologic hazards, it is imperative that the applicant analyze the stability of the portal bench and bench access road area in order to determine what the most stable reclaimed configuration should be. Ideally, all disturbed areas of the mine should be restored to the approximate original contour. The regulations of the permanent regulatory program do allow for variance in steep slope situations provi.rl.iny f:hat the conditions of Rule 2.06.5 and 9.27.9 are satisfied. The primary mechanical concern for steep slope backfill situations, which holds , whether or not a variance is granted, is expressed in Rule 4.27.3(3):