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6. Response Accepted. This item was a comment regarding a letter from the <br />Division of Water Resources. No action necessary. <br />7. Response Accepted. This item was a comment regarding a letter from the <br />Division of Water Resources. No action necessary. <br />8. Response Accepted. Colowyo added the required backfilled and regraded <br />acres to their 2007 Annual Reclamation Report Map. <br />9. Regrading to rough grade is nearing completion in the Prospect Ditch <br />watershed of the former East Pit. Technical Revision #63 (TR-63) modified <br />the post-mining topography and drainage in this area. Postmining permanent <br />drainage profiles are shown on Map 33, revised and certified 2/13/07. Plan <br />view of this drainage is shown on Map 41, Watershed Boundaries for <br />Hydrologic Modeling, revised and certified 2/14/07. Grade of the lower <br />portion of the Prospect ditch were field checked using a Suunto PM-5 <br />Clinometer. <br />Station Field Reading Map 33 <br />5 to 6.5 10 degrees 7 degrees <br />6.5 to 8.5 14 degrees 7 degrees <br />8.5 and up 16 degrees 16 degrees <br />Potentially the lower portion of this ditch is steeper than the design plan. This <br />could result in erosion of the riprap channel unless careful field design <br />practices are implemented. Some gullies have already occurred, especially <br />from flow from the north, above the substation road. Conditions are "worst <br />case" at the present time due to the lack of topsoil and vegetation. <br />At this time, the Division does not have a survey of the profile of the Prospect <br />Ditch, although the ditch is apparently to final grade along its entire length. <br />There is no practical reason to delay verification that the drainageway has <br />been reconstructed as per the approved plan with respect to the grade. <br />However, with the addition of riprap and the topsoiling of areas adjacent the <br />ditch, it is unlikely that any deviation with the approved plan would result in <br />changes to the ditch. Nonetheless, it should be recognized that a steeper grade <br />than what was planned and approved (and subsequently used in SEDCAD <br />design for the Prospect pond) could be a contributing factor to any future <br />problem that could develop in the watershed. <br />The Division requests that Colowyo submit a survey of the Prospect Ditch <br />to the Division for immediate review. <br />10. The issues raised in question 10 of the first and second adequacy letters were <br />in regards to the Prospect drainage. This issue was discussed in some detail at <br />Colowyo C-1981-019 3 Permit Renewal OS <br />