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,~, r.. 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 ricinity 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 bacldrll in the vicinity would appear to be warranted. Also, prior to bacldlling of the portals, the operator needs to demonstrate that there is no potential for water to build up behind the South Portal seals, to the extent that the integrity of the seals would be compromised c) The Roadside refuse area was temporarily stabilized in the 1980's by grading the outslopes and covering with 6 inches of soil, followed by seeding The flat top of the pile has been used az a storage yard Final reclamation will require stripping of the current soil cover, sloping the top of the pile, installation of drainage tertaces, installation of pemtartent diversions, replacement of an 18 inch soil cover,.and revegetation The reclamation plan indiptes that sufficient suitable soil material could be recovered during reclamation Crom beneath the paved parking areas of the lower bench for refuse cover. I think the documentation of the presence of sufficient suitable material in that location may be lacking, and that an alternative or supplemental borrow area may need to be identified. d) Recent monitoring of revegetated areas, as well az more casual observation, has indicated poor establishment of hefiaceous perennials in some areas. Specifically, the south Caring scopes of the CRDA-2 refuse area are stabilized by a dense stand of fourwing saltbush and a few other shrubs, but the slopes are essentially devoid of perennial herbaceous vegetation. Likewise, major portions of the North Decline are dominated by cheatgrass, with minimal perennial herbaceous cover. 1Nerseeding with perennial grasses and forts, and/or other augmentive efforts may be warranted to ensure ultimate revegetation success to allow for final bond release within a reasonable time period. Environmental/Public Safety Hazards I don't believe there are any imminent safety or environmental hazards that require immediate attention However, I believe the adequacy of the current minewater disclutrge system is questionable. Should the operator cease to monitor water levels at Well N-1 and cease to monitor and regulate discharge flow from Ou[fall 002, we would need to ensure that those functions are performed. Without this periodic monitoring and maintenance, and with no modification of the existing discharge system, there is potential for uncontrolled discharge, possibly ptastrophic, from the Northwest Intake. Geomorphic 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 that, with the current configuration of ditch and pile, a 100 year event type cloudburst could cause large scale erosion of the refuse pile, such as occurred in a similar environment at the Fruits Mine. Similarly, we need to ensure that a geomorphically appropriate permanent design is developed and implemented for the Coal Creek permanent diversion segment. The most significant concern wish respect to this issue would be the potential for the channel to alter its course at the upper end of the diversion segment, possibly eroding into the tce of the CRDA-t refuse pile. As is the case with any mine, should the operator walk away, wnditions will deteriorate and problems will develop unless we ensure that necessary monitoring and maintenance work is performed on a regular basis. Drainage related problems requiring quick response are moss likely to oavr during the monsoon season, July through early October most years, when cloudburst type storms are most likely. Wit. 5 . mc.~r a