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the ones used in the Colowyo 2009 East Pit and West Pit reclamation. The asymmetric <br />ditches lend themselves to better equipment access for cleaning and repair and are likely <br />to perform better over the extended liability period. Please consider the more <br />traditional asymmetric terrace ditch design in accordance with Rule 4.14.2(2). <br />Rule 4.05.6 - Sediment Ponds <br />13. Response Not Accepted. In Colowyo's response it is stated that the "typographical error <br />is rendered moot..." because the pages with the error, Exh. 7-20C-7 through Exh. 7-20C- <br />78, are being replaced. No replacement pages were included in the response. These <br />pages were not included on the response tracking sheet as being either removed or <br />replaced, either. The original adequacy question still stands, as follows: The footer for <br />the West Taylor Pond SEDCAD modeling states that the revision is TR-82. The correct <br />revision number is TR-81. Please change the footer information for the West Taylor <br />Pond SEDCAD modeling to TR-81 to reflect the correct revision number. <br />14. Response Partially Accepted. Colowyo has provided the additional introductory text for <br />Exhibit 7, Item 20, Part C as requested. However, Colowyo has now presented two <br />designs for the West Taylor Pond. It is not clear whether Colowyo is replacing the <br />original West Taylor Pond model or not. The confusion may stem from the fact that, in <br />response to question 13, Colowyo states that they were resubmitting pages Exh. 7-20C-7 <br />through Exh. 7-20C-78, although no replacement pages were submitted (see also question <br />13 above). The referenced pages contain the West Taylor Pond model. Additionally, the <br />West Taylor Pond model the Division currently has is based on the old post-mining <br />topography and not the post-mining topography proposed with Technical Revision 81. <br />Additionally, both pond design models use sumps or stock ponds as secondary sediment <br />control measures for the worst-case disturbance in the watershed. Please provide the <br />Division with a discussion of which West Taylor Pond design Colowyo wants to be <br />included in the approved permit document and, as in question 13 above, please <br />insure that the footnotes on the pages are correct. Please provide additional input <br />or discussion related to the hydrologic design for the West Taylor Pond, including <br />whether the sumping of water will be utilized or required as reclamation progresses <br />in the watershed. <br />15. Response Not Accepted. On Page Exh.7-20-7 Colowyo provides Table 4, which is a <br />summary of the sediment ponds in the South Taylor area. Colowyo has updated the <br />table, as requested, but there is still one problem with the table, specifically in the <br />"sediment loading" section. Sediment loading into the pond and out of the pond appears <br />to be inconsistent or inaccurate as compared to the approved SEDCAD modeling output <br />for the West Taylor Pond. The information on "sediment loading" for Section 28 and <br />Section 21 Ponds also appears incorrect. Please review Table 4 information specific to <br />the "sediment loading" section and correct as necessary.