2009-01-29_REVISION - C1981019 (4)

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Colowyo Mine TR-72 PAR3 29 January 2009 Page 2 of 8 sites, within each defined land use/vegetation community, and noted that more dramatic variation would be achievable (and would need to be reflected in the plan) for the South Taylor Area, where the projected average soil thickness is approximately 2.5 times greater than in the remaining portion of the currently approved permit area. Division of Wildlife (DOW) representatives stressed during our meeting on 20 January 2009, that they considered commitments for variable topsoil replacement to be a fundamental element of the reclamation plan, to achieve the desired vegetative diversity. They felt the best approach for delineation of varying topsoil thicknesses and treatment areas would be to include a map that would define the general areas and topographic features associated with defined soil replacement thickness ranges and enhancement treatments (such as snow fences, soil berms, etc.). Revised topsoil replacement narrative on amended pages 2.05-46 through 2.05-49 does not adequately address the concerns the Division has identified. The Division does not accept Colowyo's argument that a plan with defined thickness replacement zones is impractical because of frequent mine plan changes and limitations of recovery estimates. The vast majority of soil salvage for the original permit area has been completed, and salvage operations for the South Taylor area will be completed prior to initiation of topsoil replacement. Regardless, a defined plan based on the current topsoil stockpile volumes and future recovery projections is needed. A topsoil replacement plan delineating soil thickness averages and ranges for defined topographic areas is necessary to ensure that topsoil replacement operations will be conducted to achieve the desired ecologically significant variation in soil thickness across the landscape. The Division is requesting a map at a scale of at least 1:6000 with delineated soil depth replacement zones, and notes that South Taylor replacement thickness variability should be more pronounced than the post-2008 portions of the original permit area, due to the significantly greater volume of available topsoil projected. The Division understands that over any topsoil replacement unit there is a certain amount of variability (for example, in a unit where 8 inches of topsoil is to be replaced, one area may have 10 inches while another area may have only 6 inches) which is why the Division is requesting a map with the range of planned topsoil depths. Colowyo may wish to add specific wording to their revised text to address this issue. Please revise the cited narrative as appropriate and provide an appropriate topsoil replacement thickness map or maps, pursuant to the above discussion. Approximate acreage and general locations within which the "soil berm", and "thick and thin disarray" practices would be applied should be described/delineated. Use of snow fencing in appropriate locations to enhance shrub establishment should also be addressed. Additionally, the Division is requesting that Colowyo commit to submitting a topsoil replacement map or plate in the Annual Reclamation Report that maps the topsoil depth(s) for each reclamation unit in detail after replacement. This commitment