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intercept the flow in Poverty Gulch above that location, convey it around the mine to <br /> the Poverty Gulch streambed and discharge the flow into Poverty Gulch using a suitable <br /> energy dissipation structure". CC&V must commit in writing to the Division that no <br /> surface mining activity(including topsoil stripping and overburden removal)will take <br /> place within 400 feet of Poverty Gulch until a technical revision is submitted and <br /> approved by the Division for an acceptable reclamation/closure design alternative to the <br /> pipeline. <br /> RESPONSE: The design of the Globe Hill mine area was approved by the Division <br /> under Amendment 10. As pointed out by the Division above, Newmont is evaluating <br /> alternative designs for managing stormwater in Poverty Gulch once the North Cresson <br /> mine area is developed. We agree a pipeline is not an acceptable permanent alternative <br /> for reclamation or closure design. This alternative was envisioned as a temporary <br /> measure for routing stormwater during development of the Globe Hill mine area. <br /> Newmont will continue to evaluate alternative designs for stormwater management in <br /> Poverty Gulch and will commit to discussing these alternatives with DRMS in advance of <br /> submitting a technical revision for this activity. <br /> 57. Appendix 10, Drawing CCVSAI I-6. There are some discrepancies in the channel details: <br /> • Details 2, 3 and 4 show channel and swale designs with four and six inch design depths. <br /> This does not appear to include any freeboard which is typically six inches(for small <br /> channels) or at least half the velocity head (v2/2g). How much freeboard is included in <br /> the design and provide rationale for the freeboard design approach. <br /> RESPONSE: The SEDCAD computation for the Chicago Tunnel site has been <br /> reconfigured and Drawing No. CCVSA11-6 has been revised to include and clarify the <br /> two basins and discharge channels. The area shaded in orange is Basin ChiTun Pond <br /> which collects runoff from all non-sediment potential pollution sources and discharges <br /> into the Sediment Pond, which includes the tunnel portal, the maintenance shop, and the <br /> fuel depot. The area shaded blue is Basin ChiTun Bypass, which collects runoff from a <br /> much smaller area that only has typical drainage from natural woodlands and from the <br /> access road. <br /> Details 2, 3, and 4 show the cross sections within the ChiTun Pond basin. The <br /> conveyance channels are intended to be swales within the traffic patterns, not separate <br /> stream channels. Those swales will be armored with riprap and will be the travelled <br /> surface. No freeboard is needed since the swales will contain the flow and direct it to <br /> the Sediment Pond, which has the capacity for full containment. Accordingly, there is no <br /> practical need for additional freeboard. <br /> Detail 5 (Section D) has been added to show a conventional drainage ditch along the <br /> access road of Basin ChiTun Bypass. That section also shows the elevated location of <br /> Poverty Gulch streambed above the road that is further illustrated on Photo 3 of this <br /> document. <br /> • The drawing has section callouts A, B and C. Where are Sections A, B and C? <br /> RESPONSE: Note that those are Details 2, 3, and 4 as labeled Section A, B and C, <br /> respectively. Detail 5/Section D has been added. <br /> • There is a reference to the "Primary Drainage Channel on Back Side of Shop—2"W x <br /> 8"Deep". Where is the detail for this channel? <br /> RESPONSE: Detail 3, Section B. <br /> Page 26 of 30 <br />