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• existing rail grade construction would provide some measure of protection against elevated flows, with the coazse ballast material acting as a french drain to rapidly drain off excess flows or surface water accumulations. 38. Please provide a detailed plan view and noss section ojPond C so that the Division can verify its capacity. Response: Given the limited information provided by the Pond C design drawings as included in the WESTEC Report, a new Pond C design figure has been developed and is included with the revised drainage design calculations for insertion in Appendix B. This figure includes a pond plan view and cross-sections as noted. Please see accompanying revisions. 39. What is the spatial relationship between Ditch D10 and the Pond C embankment wall? /s there potential for the ditch to cut around any portion of the wall? Response: As a result of further review of the drainage control designs for the West Valley Fill and Pond C it has been determined that Ditch D-10 is unnecessary and the ditch has been eliminated. Ditches D-6 and D-7 will enter the remaining segment of the original ephemeral stream channel at the northern limit of Pond C. Although limited space imposes certain design constraints, discharge to Pond C at this point will minimize the potential for short-circuiting and erosion of the Pond C embankment wall to the extent reasonably feasible. • 40. Map E-3214, the Postmining Drainage Plan, does not include a permanent upland diversion for the existing refuse pile. Please revise the map to include the diversion. Response: Map 3214 has been revised to show the existing upland diversion as a permanent postmining drainage structure. Please see accompanying revisions. 41. Map E-3214 appears to have two culverts at the end of Elk Creek, yet on Map 5-100 the cross- section l-I' does not show any indication of the culverts or even the creek. Also, on Map 5-100 J- J; it does not indicate the creek location for the postmining cross-section, whereas K-K' and -/L' do show the location. Please explain or correct as required. Response: The noted maps have been reviewed and revised as appropriate for consistency. Please see accompanying revisions. 42. Map E-3111 does not include al! ditches, berms, and culverts on site. If this map is meant only to illustrate drainage features associated with 7R-29, this should be noted and a reference to additional maps made. !f not, the map needs to be revised to include all drainage structures. Also, the rymbols shown on the legend are not applied consistently on the map (ditches are shown as blue dots as well as the conventional stream rymbolJ. Please. revise the map to define al[ symbols used, and to be consistent in their application. Response: Map 3211 shows those drainage features within the Sanborn Creek, Elk Creek, and West Valley Fill areas. This map has been reviewed and revised as appropriate to • include all drainage fearures in these areas, correct any inconsistencies, and define all symbols as noted. Drainage features for other azeas including Hubbard and Bear Creeks are shown on other existing permit maps. Map 3211 has also been revised to include references to ocher maps which show mine drainage features. Please see accompanying revisions.