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Project Location: The Site is located in Jefferson County, Colorado at the northern terminus of <br />Glencoe Valley Road, approximately 10 miles north - northwest of Golden, Colorado in Section <br />25, Township 2 South, Range 71 West of the 6th Principal Meridian. The approximate latitude <br />and longitude of the Project are 39 °50'45 "N and 105 °16'54 "W, respectively. <br />Project Area Description: The Site is located in a narrow valley in the foothills of the Colorado <br />Front Range. The canyon is steep and narrow in the vicinity of the Site (approximately 1,200 <br />feet deep and 60 to 300 feet wide at the valley floor). The original valley floor in the vicinity of <br />the Site was covered with fill to form a pad for mine facilities and the creek was rerouted to the <br />north side of the canyon during mining. As part of the original reclamation work at the Site, <br />waste rock piles were capped and vegetated. These piles are located on both sides of Ralston <br />Creek. Ralston Creek is a perennial stream (which at times has no surface flow during dry years) <br />which flows southeast through the Site. Surrounding Ralston Creek is riparian area (including <br />small pockets of wetlands). Upgradient of the riparian area are grasslands, shrublands, and <br />conifer forest as well as primarily un- vegetated portions of the Mine. Approximately two miles <br />downstream of the Site, Ralston Creek flows into Ralston Reservoir which is owned and <br />operated by the Denver Water Board. <br />Project Description: The diversion plan for the Project has been agreed to by the Colorado <br />Division of Reclamation, Mining and Safety (DRMS). The Project includes the following <br />elements: <br />A phased approach will expedite this Project and the desire is to construct the upstream cutoff <br />wall during low stream flow conditions that typically occur during the late fall and winter <br />seasons. The phased approach assumes that permitting will be expedited and that winter <br />construction conditions allow construction to proceed. Dewatering of the stream and alluvial <br />groundwater, necessary for construction, will be manageable during these seasons. If the Project <br />is not phased, then the initial operation of the bypass would occur as late as fall 2012 or 2011 <br />The first phase will result in bypassing flows (up to 8 cfs) for approximately a year before a 42- <br />inch diameter steel pipe can be in operation. It is important to note that Cotter has discussed this <br />phased approach with DRMS, and DRMS has expressed conceptual agreement with moving <br />forward. <br />The following paragraphs describe each of the three phases. Additional emphasis and detail is <br />provided for Phase 1, which is the initial focus of this response. <br />October 7, 2011 <br />COTTER CORPORATION (N.S.L.) <br />PROPOSED PLAN <br />• Upstream Cutoff Wall /Diversion Intake <br />• Diversion Pipeline to Convey Upgradient Stream Flows through the Site <br />• Downstream CutoffWall/Diversion Return <br />Page 1 <br />