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2.0 TECHNICAL REVISION - TENMILE TUNNEL REHABILITATION <br />An integral component of the Climax 2010 Restart Project involves the rehabilitation of the Tenmile Tunnel <br />(TMT), located as illustrated in Figure 1. The TMT is essential to the current operation of the Tenmile decant <br />system and a critical component of the reclaim water management system for Mill operations for Climax 2010. <br />A general plan of the tunnel is illustrated on Figure 2. The original tunnel was built in the 1950s and an <br />extension to the tunnel was completed in the early 1970s. In general, the term TMT is now used to denote the <br />entire complex. The engineered slope of the tunnel is from north to south. Climax currently utilizes the <br />bulkhead and valuing systems within the tunnel to direct the flow north to the Tenmile tailing pond for water <br />treatment purposes. <br />Climax plans to rehabilitate the tunnel to a civil standard for an unlined water conveyance tunnel. The overall <br />maximum section of tunnel is 10-feet (ft) by 10-ft. with some sections as narrow as 6-ft by 6-ft. The tunnel is <br />approximately 10,103 ft in total length. In September 2001, a partial cave-in was discovered in the northern <br />section of the tunnel. Emergency repair crews were mobilized and repairs were made including the <br />installation of steel sets, rebar dowels and split-set stabilizers. It is understood that cellular concrete grout was <br />placed for a length of 216-ft at least 5-ft above the steel sets. Minimal maintenance has been conducted since <br />this work. The tunnel has subsequently been inspected by numerous consultants and company personnel. <br />These inspections form the basis for the scope of work proposed in this TR <br />The primary objectives of tl~e Climax 2010 TMT Rehabilitation Project will be to: <br />A. Rehabilitate- the tunnel to civil water-tunnel standards for a unlined conveyance systeira in an <br />environmentally responsible manner using structural, and physical stabilization measures; <br />B. Construct to relevant statutory authorities, applicable laws, .codes, guidelines, regulations and <br />. standards acceptable within the mining and.environmenta4 practice; <br />C. ,Constr4ict•to safety standards that equal.ar exceed MSHA, with dedication to making health and <br />safety a primary value. <br />2.1 Proposed Scope of Work <br />The TMT Rehabilitation work .will commence with the mobilization ofr the Contractor's equipment and <br />personnel on or about Ol June 2008. Climax water management activities require that the Tenmile Decant and <br />TMT remain operational during the major spring-runoff flow periods. Historically, this period typically begins <br />in early May and concludes in early August. Peak run-off volumes are on the order of 22,000 gallons per <br />minute (gpm). For this project, Climax is constructing a bypass pumping system that will pump on the order <br />of 10,000 gpm to allow an earlier entrance into the tunnel this summer and additional time in the tunnel before <br />the Spring 2009 runoff. <br />Based on this year's snow pack, Climax is anticipating to begin bypass pumping in early July. This will allow <br />for the timely dewatering of the tunnel in anticipation of the rehabilitation work starting in mid July. Climax <br />will be working with our water management consultants to gain as much time in the tunnel as feasible. <br />Depending on this year's spring runoff, Climax is anticipating that the tunnel will be available to be entered <br />for construction activities on or about 14 July 2008. Climax will advise the Contractor on status of the <br />dynamic runoff water volumes reporting to the tunnel and will advise of any revisions to the anticipated <br />schedule. <br />Specific TMT rehabilitation tasks include the following activities: <br />