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Technical Revision 37 Response to Adequacy Comments Page 6 • what was calculated for the "original" Pond 012 design for this watershed (e.g., 10,394 tons; 32.6 tons per acre). The modeling also indicates that there is over 300 years of storage capacity available, which is likely much longer than the "life" of this structure. Pond 012A is a pre-settling pond that SCC constructed to supplement the sediment storage capacity for Pond 012. Finally, Pond 012A is not a wastewater discharge monitoring point and, consequently, it does not matter if settleable solids are re-suspended and the discharge contains a 24-hour volume weighted settleable solids concentration greater than 0.5 milliliter per liter. Consequently, SCC does not think that the design needs to be changed. 14. Attachment 13-17 As-Built Report for Pond 014 incorrect# references Pond 013 in the Introduction and on page 13-17.1-1. Please correct these pages. Response: The references to Pond 013 have been corrected. 15. Culverts that are intended to be permanent as shoran on the Post-Mining Topography Map 20-2 should be added to the permanent structures and featurrs discussion in Tab 20 and listed in Attachment 20-1 Permanent Structures and Features Response: A culvert discussion has been added to Attachment 20-1, Permanent Structures and Features. 16. In some instances the slope information for the channels provided on Figure 13-12.3 Yoast Post Mining Channel Designs does not match the slope and profile information provided for Post Mining Channel Profiles Exhibit 20-2B. Please check the following profiles on Exhibit 20-2B; YPM-6 (Options 1 and 2), 6-3 (Option 2), 64, 7, 8, 10, 17, and 20 to ensure that the profile information is consistent with the slope data provided on Figure 13-12.3 and the supporting SEDCAD demonstrations. Response: In response to the Division's request that references to "Option 1" be eliminated from the PAP, there is • no need to check any "Option 1" slope information (e.g., YPM-6, Option 1; and, YPM-6-4). The submittal material has been reviewed to assure that the profiles on Exhibit 20-213 are consistent with the slope information on Figure 13-12.3. 17. There was no profile provided for YPM-3-2A on Exhibit 20-2B. If appropriate please add channel profile to Exhibit 20-2B. Response: Exhibit 20-213 has been revised to indicate channel YPM 3-2A. 18. Revised channel YPM-8 has a nearly 90 o turn at the lower end of the channel. This is an abrupt transition and is not a geomorphically stable configuration. The original approved design showed a moregradual bend near the lower end Please explain why the abrupt bend in the channel configuration has been added to the lower end of the channel or consider revising the channel to a more stable configuration. Response: This configuration reflects the actual location of the channel and the nearly 90 degree turn is a result of a water bar across the road. This road is proposed as a permanent road (waiting for final approval/request from the BI.M). There is no other logical way to cross the existing road. 19. The Permanent Impoundment Demonstrations Appendix 20-1.2 for Ponds 010, 013, and 014 will need to be amended to include specific information regarding water quality. The water quality discussion provided for each of these ponds is brief and only generally addresses the permanent impoundment requirements of Rules 4.05.9(13)(a). SCC did not adequately demonstrate that water quality in the ponds and discharge from the ponds meet the provisions and criteria of 4.05.9(13)(a). In each of these demonstrations, surface water quality data and details are referenced in the Annual Hydrology Reports. However, the water quality demonstration needs to be in the permit application package. Please provide a demonstration similar to those provided for the Seneca II Mine for permanent pond demonstrations for each of the . toast Mine ponds that are proposed as permanent features. This should include a comparison of permanent pond effluent to