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Underground mining activities commenced in 1976 at this mine using standard room-and-pillar methodology with a secondary pillar recovery technique within the framework of the subsidence control plan (see pages 189-190 of the permit application). Since January, 1986, the mine has been in a Division-approved temporary cessation and no mining is currently envisioned to occur until market conditions improve. Upon resumption of mining, pillaring will occur in Fault Block No. 2 until all recoverable coal is obtained. Sunland will then make a decision whether or not to extract the chain pillars of Fault Block No. 1. About 120,000 tons of recoverable coal remains in the Lower Pinnacle seam of Fault Block Nos. 1 and 2. Sunland dropped consideration of mining in Fault Block No. 3 during the Permit Renewal No. 1 application and will submit future revision if it is determined that mining in this fault block is feasible. The operation is in compliance with the requirements of this section. XVI. Explosives - Rules 2.05.3(6) and 4.08 No surface blasting is proposed for this underground mine. Therefore, the requirements of this section are not applicable. XVII. Backfilling and les 2 Information pertaining to the backfilling and grading plan is presented on pages 182-183 and 187.1 of the permit application. There are two areas to backfill and grade within the disturbed area: the portal area and the facilities area. The applicant has requested a variance from approximate original contour for the portal area, based upon steep slope mining conditions. The original slope within the portal bench area exceeded 80~. Further, Routt County Road 29 right-of-way exists immediately below the portal bench. Backfilling the portal bench cut to approximate original contour would, in the opinion of the Division, expose the users of the county right-of avay to a significant health and safety threat. Sunland proposes to partially backfill the portal bench cut. The 30-foot high portal bench cut will be backfilled to approximately 15-feet in depth, resulting in 10-foot of cover being placed above the 5-foot thick coal seam outcrop. The portal will be graded to approximately 45 degrees in slope, resulting in a 5-8 foot wide toe bench at the foot of the backfilled slope. This bench will assist in catching any debris which might fall from the bench cut or the overlying natural slopes. This configuration should assist, therefore, in preventing injury or harm to users of Routt County Road 29. Sunland has committed to the examination of the portal bench by an appropriately qualified registered professional engineer or professional geologist at the time of backfilling and grading. Therefore, the Division approves the variance from approximate original contour for the portal area. -17-