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GEM SERVICES <br /> Dawson Project—Tailings Characterization Page 1 <br /> 1 Introduction <br /> Zephyr Minerals Ltd. is preparing a mine permit application for the Dawson Project. The <br /> Dawson.Project is a proposed underground gold mine located approximately 6 miles southwest of <br /> Canon City, Colorado. GEM Services was retained to conduct a tailings geochemical <br /> characterization study as part of the mine permit application. <br /> 1.1 Project Description <br /> The Dawson Project is located on the Dawson property in Fremont County,Colorado. The <br /> property comprises a group of patented and unpatented mining claims totalling approximately <br /> 1,000 acres. Within these mining claims are three gold deposits. Only the Dawson deposit is <br /> proposed for mining. Two ore types will be mined—altered and unaltered. <br /> The proposed mining method is sublevel longhole stoping. Underground access will be via portal <br /> and decline. About 17,000 tons of granitic rock will be brought to surface from the construction <br /> of the decline. Approximately 4,200 tons of this rock will be used in the construction of the <br /> tailings storage facility, described below in Section 1.2. <br /> The proposed ore processing method is by gravity separation and flotation to recover native gold <br /> and sulfides to produce a gold concentrate that will be sold to a refinery for final extraction and <br /> purification of gold. No cyanide will be used in the ore processing. Tailings will be dewatered <br /> using a thickener and a pressure filter belt. The dewatered tailings,referred to as filter cake,will <br /> be trucked to the filtered tailings storage facility. <br /> 1.2 Filtered Tailings Storage Facility <br /> The design of the filtered tailings storage facility (FTSF) is described in detail in Amec Foster <br /> Wheeler(2016). A summary description is provided below. A schematic is provided in Figure 1. <br /> The FTSF will consist of a buttress of granitic rock and tailings filter cake compacted behind the <br /> buttress. The buttress rock will be the rock brought to surface during construction of the decline. <br /> The filter cake will be placed by end dumping and compacted by heavy equipment on top. The <br /> top will be crowned to shed precipitation. The filter cake will have the consistency of damp fine <br /> sand,having a moisture content of approximately 12%. <br /> Water management will consist of minimizing the amount of clean water contacting the tailings <br /> and containing the water that does. Diversion ditches will be constructed on the upstream side of <br /> the FTSF to intercept surface water flow and direct it around the FTSF. Collection ditches will be <br /> constructed along the sides and downstream side of the FTSF to intercept precipitation that runs <br /> off the surface of the FTSF. This contact water will be captured in the lined contact water pond. <br /> DDSldds Zephyr Dawson Tailings Chamctetization_FinaLReport,Feb.3,22,1:18 PM Feb 2022 <br />