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Comment/Objection Narrative* <br /> Since the Arkansas Valley Conservation Coalition(AVCC)filed its objection with DRMS August 31,2021, <br /> another significant failure of a tailings storage facility occurred in Brazil on Saturday January 8,2022 at the Pau <br /> Branco iron ore mine.The failure in Brazil and the potential failure here are similar since both would be a <br /> filtered tailing stack.With storms becoming more frequent and severe,the risks of a filtered tailings storage <br /> failure are increasing. Flash flooding is already an ever-present concern in our area,and the intervals between <br /> 100-year floods are getting shorter.This creates dangerous conditions that are ripe for a filtered tailings storage <br /> failure. Moreover,in the case of the proposed Dawson mine,the structural zone of the filtered tailings stack <br /> would be constructed upslope and on top of uncompacted tailings,thus constituting an upstream dam(per Dr. <br /> Steven Emerman—see his full report and biography at <br /> https://dnrwebiink.state.co.us/drms/O/edoc/l 341820/2021-08-31—PERM IT%20F I LE%20- <br /> %20M2021046%20(3).pdf?searchid=8da9d5b8-2275-42ee-al7c-229524833477). Recent history provides <br /> many examples of failures of upstream dams.The failures at Mount Polley in 2014,Samarco in 2015,and <br /> Brumadinho in 2019 were all failures of upstream dams. For that reason,the method of upstream construction <br /> is illegal in Brazil,Chile, Ecuador and Peru. In the Dawson Mine's case,a tailings failure would flow downhill, <br /> potentially into Grape Creek,and in turn,into the Arkansas River. <br /> Our Requests: <br /> 1.Thus far the DRMS has not required Zephyr to adhere to dam standards.Zephyr has(so far successfully) <br /> called the tailings dam a"filtered tailings structure zone"and not applied any known dam safety standards to <br /> the tailing stack.This essentially allows Zephyr to design the tailings stack to a lower standard more prone to <br /> failure.We implore the DRMS to apply a strict standard to the tailings dam,which would reduce the probability <br /> of failure. <br /> 2. Dr. Emerman's report filed with DRMS by the deadline of September 01,2021 states:"The application <br /> includes no consideration of the circumstances under which the tailings will undergo liquefaction and no <br /> consideration of the consequences of failure of the filtered tailings facility."The DRMS has not challenged the <br /> consequences of potential failure of the tailings dam. Please require Zephyr to produce an objective, <br /> comprehensive analysis of the potential impact and consequences of tailings liquefaction and failure of the <br /> tailings dam subsequent to completion of mining operations(not early in the mine's life). <br /> Below are links to a few articles pertaining to the Pau Branco mining-related tailings failure in Brazil posted by <br /> Dave Petley on AGU.org: <br /> https://blogs.agu.org/landslideblog/2022/01/11/pau-branco-l/ <br /> https://blogs.agu.org/landslideblog/2022/01/12/pau-branco-2/ <br /> https://blogs.agu.org/landslideblog/2022/01/13/pau-branco-3/ <br /> https://www.youtube.com/watch?v=s7lmiWYRids <br /> Another post by the Pau Branco iron ore mine operation's owner: <br /> https://www.globenewswire.com/news-release/2022/01/12/2365931/0/en/Operations-at-Vallourec-s-Pau- <br /> Branco-i ron-ore-mine-temporarily-suspended-following-the-exceptional-rainfall-i n-this-reg ion-of- <br /> Brazil.html#:-:text=Meudon%20(France)%2C%20January%2012,resulting%20in%20the%20interruption%20of <br /> Permit Number* <br /> Enter valid letter and then numbers,for example M1977999, M1999777UG or C1981201. <br /> M2021046 <br /> Permitting Action Type <br /> Amendment <br /> Select revision type or leave blank if comment pertains to a new permit application or NOI <br /> Permitting Action Sequence <br /> 2 <br /> Permit Type <br /> Minerals <br /> County <br /> Fremont <br /> Enter one county only <br /> Site Name <br /> Dawson Mine <br />