DRMS Comment Objection Intake 9/1/2021 4:05:25 PM

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2.Section 2.4.6.4 Filtered Tailings Storage Facility(FTSF):The FTSF must remain in-place indefinitely and in others words-forever stable.Some of the shortcomings of the Amec Foster Wheeler design include: a.The safety factor used by AMEC Foster Wheeler in the FTSF design is a minimum. Because the FTSF must be forever stable,the design should include additional measures to stabilize the fill slopes from mass failures and erosion,for example various methods to mitigate circular and non-circular failures,and for erosion geocells, half buried wattles,and so on. b.The design storm event of 100 years in 24 hours is inappropriate. Because the FTSF must remain in-place indefinitely the criteria should be the probable maximum flood. Additional FTSF shortcomings in the Dawson mine permit application: c.The FTSF site characterization did not evaluate whether there is any blind groundwater discharge into the stream channel below the FTSF that evaporates or flows in the stream channel substrate. In addition,there is no surface and shallow groundwater cutoff at the head end of the surface water diversion channel immediately above the FTSF to divert any surface and shallow groundwater flow in the channel substrate particularly after a storm event.The cutoff trench would add resiliency and redundancy to the FTSF subdrainage layer. d. No soil test pits were performed in the soils below the FTSF. e. No geotechnical characterization of filtered tailings was performed on the Dawson ore deposit. No field compaction testing nor variable moisture testing were performed on the filtered tailings. f.As recommended by AMEC Foster Wheeler,there appears to be no tailings contingency impoundment at the mill in the event the FTSF is not in a condition to temporarily accept the tailings,for example during snowstorms or unacceptable moisture content. For additional information on characterizing filter tailings refer to Davies, M.,2011. Filtered Dry Stacked Tailings —The Fundamentals, Proceedings Tailings and Mine Waste 2011,Vancouver, BC, November 6 to 9,2011. The Mined Land Reclamation Board should retain a reclamation warranty for at least 25 years or demonstrated survival of major storms to be used for monitoring the FTSF and reclamation of any TSF failures if Zephyr Gold fails to do so. 3.Section 2.5.4 Grading, Backfilling and Ripping, last paragraph p.31 states that"The majority of the interior roads will not be reclaimed."All surface disturbances should be reclaimed. Further,the surface reclamation warranty should be held for a minimum of 15 years.The mountainous terrain of the site is steep,the soils are easily eroded,and high-elevation plant species are slow in maturing to a stable plant community. In future,if Zephyr Gold decides to resume mining,the roads are easily re-established. Wildlife and Plants 4.Section 2.8 Exhibit H:Wildlife Information:The Colorado Natural Heritage Program(CNHP)queried their data base for"occurrences of significant natural communities and rare,threatened or endangered plants and animals."This data base query simply provides background information on flora and fauna known to exist in the vicinity of the proposed Dawson mine. It is no substitute for a careful and thorough inventory of the wildlife and plants subsisting on-site.CNHP states"CNHP information should not replace field studies necessary for more localized planning efforts,especially if impacts to wildlife habitat are possible."(APPPENDIX G:Wildlife Information, letter dated November 8,2012, p.2, paragraph 3)Biological field studies as required by the Hard Rock Metal Mining Rules 2 CCR 407-1 Rule 6.4.3(e)must be completed on the Dawson site prior to any construction and mining in order to avoid/mitigate surface disturbances of occurrences of the ten globally imperiled and State rare wildlife, rare natural plant communities,and particular plant and wildlife species known to exist in the area. Please note that the CNHP report lists ten Special Status Species and rare plant communities in the area,not just the one, Botta's pocket gopher,given in Exhibit H.All on-site Special Status Species and rare plant communities inventoried and mapped in a proper field study must be protected or their disturbance mitigated. 5.Section 2.8 Exhibit H:Wildlife Information,2nd paragraph:This paragraph acknowledges the Grape Creek Water Gap Network of Conservation Areas, but it should also acknowledge and discuss the Grape Creek Potential Conservation Area and the Bureau of Land Management Area of Critical Environmental Concern.The natural resources of those areas are in the vicinity of the Dawson site and will inform the possible natural resources on the Dawson site. 6.Section 2.8 Exhibit H:Wildlife Information:This Section should describe measures to minimize or prevent