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Rule 2.05.4 - Reclamation Plan <br />1. In the 2009 reclamation blocks in the East Pit and West Pit, Colowyo used surface <br />roughening (cross-ripping) and contour ditches with good success. Based on discussions <br />with the Division, Colowyo has revised page 2.05-30, which addresses the commitment <br />to perform additional reclamation practices in the East Pit reclamation areas. Basically, <br />Colowyo has committed to the use of surface roughening, including cross-ripping, and <br />the use of contour furrows to help reduce surface runoff and sheet flow. On revised page <br />2.05-30, Colowyo states that they will use "contour furrows approximately 4-6 inches <br />deep and 20-25 inches wide... spaced approximately 10-75 feet apart" depending on the <br />slope. Although the description provided in the text is very specific regarding the use of <br />contour furrows, the Division would like clarification whether Colowyo intends to use <br />contour furrows or contour ditches on the reclamation, as they are two very different <br />reclamation practices. Additionally, the Division does not believe that the use of contour <br />furrows and surface roughening alone will be enough to adequately control the runoff and <br />sheet flow that will be present in the reclaimed East Pit. Please clarify/confirm whether <br />Colowyo intends to use contour furrows in the East Pit reclamation and whether <br />Colowyo intends to also use contour ditches in the East Pit reclamation. If Colowyo <br />does, in fact, plan to use contour furrows, please include a description of how <br />Colowyo plans to construct the furrows. from an equipment stand point. If <br />Colowyo plans to use contour ditches in the East Pit reclamation, please include a <br />description of the general construction practices that will be used for the contour <br />ditches. Please update revised page 2.05-30 as necessary. <br />Rule 2.10 - Maps and Plans <br />2. Based on the meeting with the Division conducted on 13 October 2010, Colowyo intends <br />to modify the design of the stock tanks so they sit slightly outside of the post-mining <br />channel. Water will be diverted from the post-mining channel, into the stock tank, then <br />back into the post-mining channel. The plan as depicted on Map 12 - Hydrology, South <br />Area, shows these stock tanks in the middle of the post-mining channels. Please modify <br />Map 12 to show the exact location of the stock tanks, as discussed in the 13 October <br />2010 meeting. Please also modify all of the figures included in the SEDCAD <br />modeling for the Prospect Pond to show the exact location of the stock tanks. The <br />map and figures should also contain the routing detail of the runoff from the post- <br />mining channel, into the stock tank, then back into the post-mining channel. <br />Map 12 - Hydrology, South Area, shows reclamation that has been completed at the <br />Colowyo Mine as it relates to backfilling and grading and post-mining channel <br />construction. Given the ongoing and continual nature of the reclamation at the Colowyo <br />Mine, this map will never be a completely accurate representation of what is actually <br />reclaimed on the ground except for at one specific point in time. The map does, however, <br />need to be accurate for any given reclamation year. Colowyo will need to update Map 12 <br />on a yearly basis to show the reclamation that has occurred to date. The Division <br />recommends that Colowyo provide a new copy of Map 12 in the spring of each year <br />showing the previous year's reclamation. The map will need to be submitted as a Minor <br />Revision to the permit.