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APPENDIX B <br /> MITIGATION PROJECTS <br /> Mitigation Projects <br /> SGC is listing nine mitigation projects which will offset potential loading increases resulting <br /> from waters returning to their natural flow paths around the Sunnyside Mine. The projects are <br /> listed as "A" list or primary(those projects on which work will commence after the hydraulic <br /> seal valves are closed)and "B" list or secondary(those projects which may need to be completed <br /> in order for the dissolved zinc concentrations to meet the criteria at Reference Point AR-72). The <br /> secondary list will be evaluated after the primary list has been completed and the reference water <br /> quality can be monitored to see the effects of the completed primary projects on maintaining the <br /> dissolved zinc loading from the Upper Animas Basin. Completion of all projects on the <br /> secondary list may not be necessary if the reference water quality in the Animas is being <br /> maintained without them. <br /> SGC will evaluate, engineer and complete work in a workmanlike,safe, proper and expedient <br /> manner according to the work plans attached to this Consent Decree. All work on mitigation <br /> sites will focus on reducing the dissolved zinc loading at the reference point and not on meeting <br /> specific standards at each mitigation site. <br /> Mitigation on sites not owned or controlled by SGC will require permission of property owners <br /> to enter their property to evaluate and do mitigation work. Should SGC identify more beneficial <br /> projects, they will replace other projects on the "B" or secondary project list with concurrence <br /> from WQCD. <br /> BB=2 "A" List- Primary Projects <br /> (1) Sunnyside Mine Pool <br /> After closure of the valve in the property line seal, SGC will introduce high pH <br /> water into the pool during filling of the mine pool. The projected target pH of <br /> mine water would be 8.0 to 9.0 versus current 6.5 at the American Tunnel. This <br /> will allow for the mine pool to reach equilibrium from a basic pH as oxygen is <br /> depleted rather than from an acid pH. <br /> (2) Mine Waste Dump- South Fork of Cement Creek <br /> 23663-/.L/ZW 1 b <br />