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dewatering trench will be constructed with designed sumps where waters will be allowed to collect in <br />excavated depressions and then discharged into the proposed surface water system and sediment ponds. At <br />the proposed outlet to the sediment pond waters will be discharged into the receiving stream only after the <br />collected waters are clear of suspended sediments and/or other potential pollutants. Therefore, in <br />accordance with Rule 6.4.4(c) & (f), the Division requests that you provide a revised copy of the Ivline <br />Plan Map to show the location(s) and configuration(s) of [he settling ponds. The Division also requests', in <br />accordance with Rule 6.4.4(c) & (f), that you provide a plan view and representative cross section of the <br />pit excavation, dewatering trench, designed sumps, sedimentation pond, discharge point, and receiving <br />stream. (Please keep in mind that since the sedimentation pond is well within 400 feet of the channel of <br />the Yampa River, the sediment pond designs will need to conform to the criteria listed below in Item 9). <br />Please address. <br />9. Review of the mining and reclamation plan maps (Maps 3 & 4) indicates there are a number of locations <br />where pit excavation will occur within 400 feet of either Trout Creek or the Yampa River. In order to <br />ensure the structural integrity of the channels for Trout Creek and the Yampa River, pit slopes, interim <br />berms, and reclaimed slopes throughout the life of the mining operation, the proposed mining plans will <br />need to be revised to conform with the criteria listed in the Division's August 1993 In-Stream Aggregate & <br />Extraction Reclamation Guidance Document for all areas of mineral extraction that will occur within 400 <br />feet of either Trout Creek or the Yampa River. (Please see attached guidance document). The following <br />options are acceptable to the Division: <br />Option A :The applicant may revise the mine plan map to show the boundaries of the "Floodway" of Trout <br />Creek and of the Yampa River and clearly show that all pit excavation will occur outside of either <br />Floodway. In conjunction, the applicant should revise the narrative in the mine plan by providing a <br />commitment to no aggregate extraction within the floodway of either Trout Creek or the Yampa River. <br />Option B :The applicant may revise the mine plan and mine plan map to clearly demonstrate [hat no <br />mining will occur within 400 feet of the channel of either Trout Creek or the Yampa River. <br />Option C :The applicant may keep the proposed mining limits upon submission of an approvable plan and <br />cross-sectional design for side channel spillways allowing for pressure equalization of Floodwaters between <br />[he pit excavation and the channels of either Trout Creek or the Yampa River. For acceptable design <br />criteria, please refer to the attached guidance document (Appendix D and Figure D-16). <br />Option D :The applicant may keep the proposed mining limits upon submission of an approvable plan and <br />cross-sectional design for channel riprap slope protection, pitside riprap slope protection, and interim berm <br />slope protection for any locations within the affected land where excavation or interim berms will occur <br />within 400 feet of the channel of either Trout Creek or the Yampa River. For acceptable design criteria, <br />please refer to the attached guidance document (Appendix D, Figure D-5(a), and Figure D-5(c)). <br />10. Letters of objection to the application have been received on April 5, 2001 and May 8, 2001 from <br />Loretta Van Norstrand expressing concems over the applicant's projections of mining related impacts to <br />groundwater, riparian areas, and mature cottonwood trees. Please respond to the objectors concems and <br />clarify if the applicant's projections for potential impacts' addressed potential impacts to groundwater and <br />vegetation resources outside of the proposed affected land. (Please see attached objection letters). <br />11. The applicant indicates on page 3 that 2000 feet of haul road will be constructed to connect Routt <br />County Road #179 to U.S. Highway 40. The applicant also proposes (on page 8) to construct a mine <br />access road approximately 50 feet wide. Review comments from Allen Sorenson of the Division regarding <br />