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-35- Runoff from disturbed areas is routed to sedimentation ponds through the use of collection ditches. These sedimentation ponds reduce the levels of settleable and suspended solids to levels that meet N.P.D.E.S discharge standards. After treatment, water is discharged back to the original stream course downstream of the disturbed areas. One smal] disturbed area (one acre in size) dces not pass through the sediment pond system. The area is the upper bench, which is used for the water tank. There are no activities planned for this bench that would generate large amounts of sediment. The operator, therefore, proposes to route the water through a small shallow sediment basin prior to discharge to the receiving stream. The Division has granted the operator a small area exemption for this area. The proposed sediment control plan will be adequate to treat the runoff from this small area. A large-scale pond is not practical or warranted for the limited extent of disturbance on this bench. To prevent excessive siltation from prematurely clogging the 260 foot Lewis Gulch Fill culvert, the Division is requiring the operator to construct a small sediment trap (2-3 foot deep excavation) at the inlet of the culvert to trap small amounts of streambed load prior to it entering the culvert. Cleaning a culvert of this size and length would be difficult if allowed to clog with sediment. The following stipulation addresses this concern. Stipulation No. 7 THE OPERATOR SHALL CONSTRUCT A SEDIMENT TRAP (3 FEET DEEP AND lU FEET LONG) AT THE INLET OF THE LE'~JIS GULCH FILL CULVERT PRIOR TO COMPLETION OF THE FILL. With the acceptance of the above stipulations, the Division's review of the drainage and sediment control system, mine water treatment system, and alternative sediment control system shows the operation to be in compliance with the design and performance standards of the Regulations. XVIII. Backfilling and Grading -Rules 2.05.3(6)(b). 2.05.3(9 Reclamation plans for backfilling and grading were provided on pages 81-86. Initial construction of the entries and preparation of the site for mining will result in the first stage of reclamation of the existing disturbance. Existing spoil material will be used to fill over the steel archway entries thus eliminating part of the highwall. Additionally, the proposed ramp to the underground development waste pile will fill an existing cut in the hillside. Spoil material will also be used in the construction of the Lewis Gulch Fill. The fill in Lewis Gulch is necessary to provide sufficient space for the construction of a sediment pond and a truck turn-around area. Twin Pines Coal Company, Inc., on page 92a, has proposed to remove the 8800 cubic yard Lewis Gulch fill and the 260 foot culvert at the time of final reclamation. The fill material will be placed in lifts on the portal bench and dill be graded to approximate the original contours.