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currently in the permit text continue to be appropriate. Colowyo is open however, to <br />adding text to its Annual Hydrology Report as requested in the 22 June 2010 letter from <br />the Division reviewing the 2007-2009 Annual Hydrology Reports. This text will <br />specifically state that a limited number of low impact spoil springs are expected to develop <br />occasionally but that their aerial extent and low level or non-existent surface flow will <br />have a very minor impact on surface (and shallow groundwater/perched aquifer) water <br />quality and quantity in the future. <br />Rule 3.02.2 -- Determination of Bond Amount <br />8. Pursuant to Rule 3.02.2(4), Colowyo may provide the Division with a midterm <br />reclamation cost estimate for review and approval. The Division completed a reclamation <br />cost estimate with Permit Renewal 05 (approved 15 September 2009) and determined that <br />the amount of bond held was sufficient to cover the remaining reclamation in the event of <br />pen-nit revocation and bond forfeiture. Since equipment costs have not been updated since <br />that time, the RN-05 estimate is still valid. Colowyo did submit a reclamation cost <br />estimate under the cover of Technical Revision 85 but the Division deemed that revision <br />incomplete on 1 March 2010. The Colowyo estimate included changes to the mining and <br />reclamation plans that were proposed in Technical Revision 81 that have not yet been <br />approved. If Colowyo chooses to include a midterm review reclamation cost estimate it <br />should be for the currently approved reclamation plan. <br />Colowyo's Response: <br />Upon the approval of TR-81, Colowyo will proceed with TR-85, which will update the <br />bond post-mining topography and incorporate the most recent cost estimates for <br />Colowyo's bond. <br />Rule 4.05 - Hydrologic Balance <br />9. The Division and Colowyo have had many discussions over the last five plus years <br />regarding the long-term hydrologic stability of the Prospect watershed. While these <br />discussions have been mainly focused on the Prospect watershed, they are equally <br />applicable to the East Taylor and West Pit watersheds (for the West Pit) and the Section <br />28 and West Taylor watersheds (for the South Taylor Pit). These discussions have <br />centered on controlling and slowing the runoff from the long, steep reclaimed slopes at the <br />Colowyo Mine. While Colowyo did implement some of the ideas during the 2009 <br />reclamation season (contour ditches and ripping the topsoil prior to seeding), the Division <br />is requesting a comprehensive and detailed plan for controlling the runoff from the <br />reclaimed slopes, including, but not limited to, contour ditches, ripping, straw bales, <br />reconstructed drainage channels, stock ponds and the possible addition of non-NPDES <br />sediment ponds within the reclaimed area. This plan needs to be specific enough for each <br />of the pits/watersheds to address their unique characteristics. The plan must be prepared <br />by Colowyo and approved by the Division ahead of reclamation and with sufficient detail <br />to ensure proper implementation in the field. The locations of runoff control measures, <br />such as contour ditches and stock ponds, need to be planned prior to reclamation to ensure <br />they function as designed and have the desired effect of controlling and slowing the runoff <br />and providing adequate sediment control. While a minor amount of "field fitting" may be <br />necessary, the location should be well thought out based on the topography and other <br />characteristics of the watershed. Sediment and runoff control features should be located <br />on a map, to ensure that they are properly located and in the necessary area(s). This plan