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? T <br />provisions and criteria of 4.05.9(13) (a). In each of these demonstrations, surface water quality <br />data and details are referenced in the Annual Hydrology Reports. However, the water quality <br />demonstration needs to be in the permit application package. Please provide a demonstration <br />similar to those provided for the Seneca lI Mine for permanent pond demonstrations for each of <br />the Yoast Mine ponds that are proposed as permanent features. This should include a <br />comparison of permanent pond effluent to appropriate stream segment standards. Please refer <br />to the Seneca II Mine Permanent Impoundment Water Quality and Water Right Demonstrations <br />permit application package pages 7-379 through 7-387. <br />20. In the Permanent Impoundment Demonstrations Appendix 20-1.2, SCC indicates that they have <br />a water right for Pond 010 and no water rights for Ponds 013 and 014. For Pond 010, please <br />provide the water right decree or reference its location and summarize the decreed amount and <br />Case No. in the Permanent Impoundment Demonstration. For all three permanent pond <br />requests (010, 013, and 014) appropriate application materials should be submitted to the <br />Office of the State Engineer for the permanent structures. All impoundments that are intended <br />to be retained as permanent postmining features shall comply with applicable State Engineer <br />rules and regulations. Under the State Engineers rules a permit is required but water rights are <br />not required for Livestock Water Tanks or Erosion Control Dams, which may be applicable to <br />Ponds 013 and 014. State Engineer and DRMS approval shall be obtained before bond release <br />can occur. <br />21. The Permanent Impoundment Demonstration for Pond 012 is not appropriate at this time since <br />the pond configuration is not stable and a new design and subsequent as-built will be submitted <br />for Pond 012. Please withdraw the Permanent Impoundment Demonstration for Pond 012 from <br />TR-37. <br />22. For the Stockpond ST-1 Permanent Impoundment Demonstration, insufficient information was <br />provided regarding the spillway capacity. There was no SEDCAD demonstration provided as <br />referenced in the demonstration. The peak flow from the 25-year, 24-hour storm event, the <br />depth of flow and freeboard with emergency spillway flowing at design depth were not <br />provided. Please provide the SEDCAD run and information listed above. <br />23. Under the capacity discussion, SCC indicates that "since the capacity is under 2 ac. ft. limit, the <br />State Engineer's office does not need the review the permanency request". Please provide your <br />reference for the two acre-feet limit. Based on our discussions with the Office of the State <br />Engineer, the two acre-feet limit only applies to Erosion Control Dams with respect to the <br />location of an outlet at or below the two acre-feet storage volume level. Permits or notification <br />may still be required by the State Engineer for these structures. This structure was legally <br />constructed under DRMS jurisdiction. However, at the time of bond release all impoundments <br />including stockponds that are intended to be retained as permanent postmining features shall <br />comply with the applicable State Engineer rules and regulations. State Engineer and DRMS <br />approval shall be obtained for this structure before bond release can occur. <br />24. An error was noted under the capacity discussion of the Stockpond ST-1 Permanent Pond <br />Demonstration, SCC states that "The Factor of Safety from this analysis shows 1.3". This <br />should read "A safety factor greater than 1.3 was calculated by this analysis."