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a) At least four principle species including a minimum of three cool season perennial grasses and a minimum of 1 perennial forb shall be established. . b) Each principle species shall contribute no less than 3% relative cover. c) No single species shall contribute in excess of 50% relative cover. 9. Question 23 requested that Colowyo include a cost for cleaning the sediment ponds over the 10-year liability period in the bond estimate. Please include this task in the reclamation cost estimate. December 28. 1995 Letter (MR-33) 10. Question number 2 in the Division's letter reads as follows; Rule 4.05.6(6) states that the Division may approve a sedimentation pond that relies primarily on storage to control the runoff from the design event when it is demonstrated by the operator that the water will be safely removed in accordance with current, prudent, engineering practices. Colowyo needs to address how the water will be safely removed from all ponds that rely on storage to control the runoff. According to the State Engineer's Office, water in excess of 2 acre feet must be released from the pond within 36-hours unless water rights are obtained (C.R.S. 37- 87-122). The Division reviewed all of the ponds recently constructed at the mine to determine if the pond would properly treat and pass the 10-year event with a "permanent pool" of water up to the primary spillway (Prospect Pond, Section 16 Pond, West Pit Pond and East Taylor Creek Pond). The East Taylor Creek Pond appears to be the only sediment pond that may not safely pass or treat the 10-year event if there is a "permanent pool" due to the different spillway elevations (two feet rather than three feet). If the water level in the pond was lowered one foot below the principal spillway, theoretically, the spillways will safely pass the 10-year event. Two issues need to be addressed; a. Colowyo must demonstrate how water will be safely removed from all ponds that rely on storage to control runoff, to be in compliance with the State Engineer's Regulations requiring release of water in excess of 2 acre-feet within 36-hours, and to maintain.adequate capacity to contain or treat runoff from storms or snowmelt which occur while the pond is already storing water. b. Colowyo must demonstrate that the Taylor Creek Sediment Pond will safely pass the 10-year, 24-hour storm event if there is a "permanent pool" of water in the pond. Colowyo could address this issue by either, lowering or perforating the riser to drop the water level or marking the maximum storage elevation on the riser.