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Page 6 of 9 <br />The Division has no further concerns. The Sedcad designs in the November 29, 2011 submittal reflect <br />that the primary discharge pipe inverts were raised in elevation. <br />13. A) It does not appear that the primary and emergency discharge structures for the three sediment ponds <br />are shown on Map 2.05.3(3) -1. Please add these structures to the map since they are part of the surface <br />water hydrology. <br />The Division has no further concerns. Map 2.05.3(3) was renumbered as Map 2.05.3(4) -1 and revised <br />appropriately in the submittal dated November 29, 2011. <br />B) In Table 2 on page 4 of the Arcadis report in Appendix 2.05.3(4) -1, a primary discharge pipe length of <br />247 feet is given for sediment pond NHN -002. However, referring to Figure 3 of the same report, the <br />pipe length appears to be about 60 feet. Please clarify. <br />The Division has no further concerns. Table 2 was revised in the November 29, 2011 submittal. <br />17. A) The Sedcad hydrology design for Channel -1 consists of one ditch design page that is located at <br />the back of Appendix 2.05.3(3) -1, "Sedcad Runs for Culverts". Please include additional design pages <br />that show how the peak discharge for Channel -1 was obtained, as was done for the other ditches. Also, <br />in order to avoid any confusion, please consider moving the channel -1 Sedcad run pages to a more <br />appropriate section, such as Appendix 2.05.3(4) -2, "Sedcad Runs for Pond and Diversions ". Also, <br />please consider adding Channel -1 to Table 4: Ditch Design Parameters on page 7 of Appendix <br />2.05.3(4) -1, "Arcadis Report on Sediment Control ". <br />The Division has no further concerns. The Sedcad re- designs for Channel -1 were included in Appendix <br />2.05.3(3) of the November 29, 2011 submittal. <br />B) In Appendix 2.05.3(3) -1, "Sedcad Runs for Culverts", there are Sedcad design sheets for culvert C -1 <br />that use a peak discharge of 4.78 cfs and a culvert diameter of 18 inches. These parameters also appear <br />in the Culvert Table on Map 2.05.3(3) -1 for that culvert. However, directly after those design pages is <br />one design page for culvert C -1 that uses a peak discharge of 51.82 cfs. Please explain. <br />The Division has no further concerns. The culvert C -1 design page using 51.82 cfs was deleted. <br />C) The Culvert Table on Map 2.05.3(3) -1 states that the subwatersheds for culvert C -13 are SW1 -B and <br />SW -FA. However, referring to Map 2.05.3(3) -1, it appears that the subwatersheds should be SW-1C and <br />SW -FA. If this is correct, please revise the Sedcad designs and the Culvert Table on Map 2.05.3(3) -1 for <br />culvert C -13. <br />The Division has no further concerns. In the November 29, 2011 submittal, Map 2.05.3(3) was <br />renumbered as Map 2.05.3(4) -1 and revised. The Sedcad design was also revised. <br />D) Please add the D50 riprap size of 6 inches for ditch NHN -002 South w /Riprap to Table 4.• Ditch Design <br />Parameters on page 7 of Appendix 2.05.3(4) -1, "Arcadis Report on Sediment Control ". <br />The Division has no further concerns. The text in the Arcadis report was revised in the submittal dated <br />November 29, 2011. <br />19. In the May 26, 2011 submittal cover letter, Western Fuels explained the justification for using the curve <br />number but did not revise any text since the culvert was not in the mine's disturbed area. The Division's <br />question could have been worded better. The justification for the curve number of 91, used in the Sedcad <br />