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• Sediment ponds Nos. 4, 5, 6, 9, 10 and 13 will have a principal spillway <br />consisting of a pipe installed just above the maximum sediment depth. Ponds <br />#4, #5, and #6 were originally designed with a combination principal and <br />emergency spillway. Redesign information providing for separate spillways on <br />these ponds is given in Appendix 13-2. The principal spillways will have normally <br />closed manually operated gates or valves to control dewatering of the ponds. <br />Sediment ponds #1, #2, #7, #8, and #11 will require pumps for dewatering, since <br />surrounding ground elevations are higher than the sediment pond bottom <br />elevations. A portable pump will be rented for this application. The pumps will <br />be operated manually when required. Manual dewatering valves can function as <br />slow passive dewatering devices and also insure adequate detention time, so <br />that effluent limitations will not be exceeded. After settling, the water level will <br />not be allowed to stay above the maximum design sediment level as marked by <br />sediment stakes or measurements from the spillway. <br />Primarily due to the lack of capacity in sumps in the Roadside North portals, <br />Pond 12 was designed in 1997 to act as a surface water treatment pond for mine <br />water discharge. The primary spillway is controlled by a manually operated valve <br />• which allows regulation of the water level and detention time. Design information <br />is included in Appendix 13-2. Pond 12 was partially reclaimed during the fourth <br />quarter of 2001 because it was no longer needed for the operation. Additionally, <br />the bottom of the pond failed and caused anon-compliance discharge on <br />November 18 and19, 2001. <br />A new pond will be constructed concurrently with the reclamation of the North <br />Portal. The design for this pond is presented in Appendix 14-6 beginning on <br />page 14-6-53. This new pond is designated Pond #13 and is shown on Exhibit <br />8C. <br />Existing ponds have been certified by a registered professional engineer <br />subsequent to installation or modification. Certification of any other sediment <br />ponds will be submitted immediately following construction or modification in <br />accordance with Rule 4.05.6(7). Quarterly sediment pond inspections will be <br />performed to monitor the sediment level in each pond. The sediment will be <br />13-7 (Rev. 11 /01) <br />