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b. The backfill into the open cuts must be placed in controlled horizontal lifts, not exceeding 2 feet thickness, and compacted by a minimum of four passes with a rubber tired loader, haul truck or other rubber tired heavy equipment. The fill must be compacted to a minimum of 90 percent maximum achievable dry density. A minimum of one density test, completed in accordance with an appropriate ASTM standard, must be completed for each backfilled open cut cell, with the density testing results to be included in the annual reclamation report. c. The initial lift of backfill must be placed onto e rough surface in order to assure a good bond between bedrock and backfill. If the floor of the open cut to be filled is smooth, which might be anticipated on bedding plane surfaces or partings, the surface must be ripped or blasted to leave a roughened surface for initial backfill placement. Similarly, the surface of each backfill lift must be scarified or roughened prior to placement of subsequent backfill lifts, in order to assure adequate bonding between lifts. d. The operator needs to commit to a maximum finished slope for the backfill of 2:1 and a maximum depth of fill of 25 feet. If the operator proposes to leave any backfill slopes steeper than 2:1, or create fills that will be deeper than 25 feet, the Division will require that the backfill material be tested in the laboratory for shear strength characteristics and that a theoretical slope stability analysis be completed demonstrating that the proposed finished slopes will be stable with a minimum safety factor of 1.5 (refer also to other demonstrations required under item 4 above). e. If it is determined that either clay or geosynthetic liners are required for the proposed open cut fills, the Division will require that the shear strength characteristics o£ the liner materials and liner interfaces be determined by laboratory testing, and that a theoretical slope stability analysis be completed demonstrating that the fills will be stable with a minimum safety factor of 1.5. 6. CONTOUR DEPRESSION FILL AREA STABILITY AND RECLAMATION The applicant has not adequately addressed Division concerns regarding the stability of the proposed contour depression fill area. fissential construction details such as foundation preparation, placement of lifts, material blending methods and testing, and a representative cross-section (fiRHIBIT fi-l, CONTOUR DEPRESSION) of the disposal area have as yet not been 6