2014-11-21_REVISION - C1996083 (4)

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Susan Burgmaier -4- November 18, 2014 d. Culvert G -5, shown on Map 21 -3, carries flow from Culvert D1 to Ditch D2 is not listed on the culvert summary table of Page EXH -8 -31, and we cannot locate design information for this culvert in the proposed or approved permit application materials. Please add Culvert G5 to the culvert summary table on page EXH -8 -31, and provide design information for the culvert or specify the location of a currently approved design. BRL: Culvert G -5 was added to the permit package as part of TR -87. It is part of the Pond D hydrologic network and will be included in the technical revision application that addresses the TR -77 stipulation No.34, submittal due no later than January 15, 2015. DRMS: There are several inconsistencies in the flow values for Ditch H1 and Culvert H1 presented in various locations in the permit: • The flow value for Ditch H1 on proposed page Volume XI, App B -8 is listed as 3.07 cfs. • The flow value listed on the design information for Ditch H1 provided on currently approved page Exh -8 -166, is 23.35 cfs. The value was adjusted upward with TR -84, which included plans for a clean water diversion above Gob Pile #3. However, it would appear that much of the flow described as flowing to Ditch H1 actually flows through the Gob Pile #3 Clean Water Diversion Ditch directly to Culvert H1. • The flow value for Culvert H1 on proposed page EXH -8 -31 is 3.07 cfs. Currently approved EXH -8 -31 lists the flow value as 23.35 cfs. • The label for Ditch H1 has been dropped from the version of Map 21 -3 submitted on September 24, 2014. It would appear that the flow value for Culvert H1 should be 23.35, and the flow value for Ditches H1 and H2 should be 0.62 cfs and 3.07 cfs, respectively. Please verify the flow values reported for Ditches H1 and H2 and Culvert H1, and correct the values so that they are consistent throughout pages EXH- 29iii, EXH -8 -31, EXH -8 -166, and Volume IX App B -8, and restore the label for Ditch H1 on Map 21 -3. Need to cross reference TR -91 with TR -84 BRL: The flow for ditch H1 should be 2.57 cfs, and the flow for ditch H2 should be 0.62 as shown on page EXH -8 -166. Page Exh 8 -166 has been revised to show the correct flow of 2.57 cfs for Ditch H -1. The difference between the approved flow of 3.07 and 2.57 cfs is 0.50, the mine water discharge, which is a discharge that is no longer occurring. The mine water discharge has also been removed from all Clean Water Ditch Segments approved with TR -89. Pages Volume XI, App. B -67, 72 and 73 are attached. The flow for Culvert H1 has been revised to a value of 23.73, page Exh. 8- 168 has been revised. This flow value is a sum of flows from Ditch H -1, the clean water