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t; IRIS <br />MITIGATION AND DESIGN, INC. <br />Environmental Consulting <br />comments in a letter to the USFWS dated October 25, 2011. <br />IRIS MITIGATION AND DESIGN, INC. <br />2022 Arapahoe Street <br />Golden, Colorado 80401 <br />Phone: 720 - 272 -1985 <br />bleisure@irismitigation.com <br />USFWS commented on the initial Biological Assessment whereby IRIS responded to the <br />The USFWS then prepared a Biological Opinion which became part of the USACE permit <br />requirements dated November 25, 2011. This 2012 Schwartzwalder Mine Actual Area Impact <br />Report updates the USACE and USFWS on the construction activities that were completed at <br />the Site in 2012 and is required as part of the USAGE permit and the USFWS Biological <br />Opinion. This report also describes what mitigation activities need to be completed as a result <br />of the actual area impact (some of which have been completed to- date). <br />Proiect Background <br />The overall Schwartzwalder Mine project had three distinct phases and the 2011 USACE permit <br />and 2012 construction activities conclude Phase 1 of the project. Construction of the permitted <br />upstream cut -off wall and installation of the 18 -inch pipeline was completed in April 2012. In <br />April 2012, the Ralston Creek irrigation system was installed. Additional fine tuning of the <br />Phase 1 cut -off wall, 18 -inch pipeline, and irrigation system installation was completed in May <br />2012. <br />Phase 2 of the project included the proposed construction of a downstream cut -off wall, and a <br />42 -inch temporary diversion pipeline, mostly above ground and around the Site. Based on more <br />recent data and technical information, Cotter does not believe that Phase 2 is prudent or <br />needed at this time. Therefore, Cotter believes that Phase 3 should be the next Phase at the <br />Schwartzwalder Mine to be considered for USACE permitting with USFWS consultation. <br />Schwartzwalder Mine Actual Area Impact Page 2 <br />January 2013 <br />