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tunnel. Also, the geomorphic consequences of wrapping the final diversion channel along the upper perimeter of the Roadside Refuse Pile may deserve further consideration. b) Handling of seepage water in vicinity of South Portals. Water from pre-law mine workings discharges seasonally in the immediate vicinity of the South Mine Portals. A plan to ensure that seepage will not compromise stability of the backfill in Ure vicinity would appear to be warranted. Also, prior to backfilling of the portals, the operator needs to demonstrate Utat there is no potential for water to build up behind Ute South Portal seals, to Ute extent that the integrity of the seals would be compromised c) The Roadside refuse area was temporarily stabilized in Ute 1980's by grading Ute outslopes and covering with 6 inches of soil, followed by seeding. The flat top of the pile has been used as a storage yard. Final reclamation will require stripping of the current soil cover, sloping the top of the pile, installation of drainage terraces, installation of permanent diversions, replacement of an 18 inch soil cover, and revegetation. The reclamation plan indicates that sufficient suitable soil material could be recovered during reclamation from beneath the paved parking areas of the lower bench for refuse cover. 1 think the documentation of the presence of sufficient suitable material in that location may be lacking, and that an alternative or supplemental borrow area ntay need to be identified. d) Recent monitoring of revegetated areas, as well as more casual observation, has indicated poor establishment of herbaceous perennials in some areas. Specifically, the souUt facing slopes of the C1tDA-2 refuse area are stabilized by a dense stand of fourwing saltbuslt and a few other shrubs, but the slopes are essentially devoid ofperennial hefiaceous vegetation. Likewise, major portions of the North Decline are dominated by cheatgrass, wiUt minimal perennial herbaceous cover. Interseeding with perennial grasses and (orbs, and/or outer au®nentive efforts may be warranted to ensure ultimate revegetation success to allow for final bond release within a reasonable time period. EnvironmentaVPublic Safetv Hazards I don't believe there are any imminent safety or environmental hazards that require immediate attention. However, I believe Ute adequacy of the current tninewater discharge system is questionable. Should the operator cease to monitor water levels at Well N-1 and cease to monitor and regulate discharge IIow From Outfall 002, we would need to ensure Utat those functions are performed. Without this periodic monitoring and maintenance, and nth no modification of the existing discharge system, there is potential for uncontrolled discharge, possibly catastrophic, from the NorUnrest Intake. l7eomorpttic questions regarding the CRDA-2 upper diversion and top of pile topography need to be resolved and prudent design implemented during final reclamation. My concern is tha4 with Ute current configuration of ditch and pile, a 100 year event type cloudburst could cause large scale erosion of the refuse pile, such as attuned in a similar environment at the Fmita Mine. Similarly, we need to ensure [hat a geomorpl»cally appropriate permanent design is developed and implemented for the Coal Creek petmanent diversion segment. The most significant concern wiUt respect to Uus issue would be the potential for Ure channel to alter its course at Ure upper end of the diversion segment, possibly eroding into the tce of the CRDA-I refuse pile. As is the case wiUt any mine, should Ure operator walk away, conditions will deteriorate and problems will develop unless we ensure Utat necessary monitoring and maintenance work is performed on a regular basis. Drainage related problems requiring quick response are most likely to occur during Ute monsoon season, July through early October most years, when cloudburst hPe storms are most likely. ~~. 5 ..~c.H a