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Existing Mining Plan <br /> The operator has mined this site intermittently since the issuance of the DRMS permit in 1987. The <br /> operation includes a surface extraction area (its limits being defined by the existing quarry wall),a <br /> below-grade quarry floor,a level staging area and product stockpile pad,topsoil stockpile areas, <br /> stormwater controls,and an access road. The mined area within the existing permit boundary is small <br /> and has room to grow by several more acres. <br /> Activities occurring on the site consist of stripping and stockpiling topsoil for later use in reclamation, <br /> stripping the overburden down to the top of the obsidian deposit in the area to be mined, drilling and <br /> blasting the obsidian,and moving and stockpiling the product for offsite sale and use. The nature of the <br /> obsidian deposit is that there is no waste or reject material produced during the mining and handling of <br /> the obsidian. The material is also very durable and competent(i.e., not weathered and fractured)which <br /> allows it to remain stable in a steep highwall slope over the long-term. <br /> The overburden that is stripped is not considered a product. It is not being processed, sold,or exported. <br /> It has been used to build the operations pad and earthen stormwater controls. The overburden lying <br /> above the obsidian to be mined is stripped, and the margins of this stripped area are graded to a stable <br /> slope (about 3H:1V)above the highwall being mined. All "excess" overburden that is stripped is hauled <br /> to an onsite stockpile location, where it is shaped,topsoiled and revegetated for later use. <br /> The topsoil that is stripped during the operation is stockpiled and seeded to protect it for later use in <br /> reclamation. Wherever possible,the operator performs reclamation concurrent to the mining <br /> operation. Weed control and stormwater control are currently carried out. <br /> In the past the pit has expanded incrementally,with topsoil and overburden stripped in advance of the <br /> highwall. This method has been appropriate for the rate of mining up until the present. <br /> Equipment used on the site includes bulldozer,wheeled loader,tracked drill, haul truck, crusher, and <br /> conveyor/stacker. <br /> All explosives,fuel, lubricants,and other materials used onsite are either delivered for use that day or <br /> stored properly: in clearly identified areas segregated from other site activities, secured, and with <br /> sufficient secondary containment as needed. These practices will be continued under the 112c permit <br /> mining plan. <br /> Mining Plan under Proposed Expansion <br /> The proposed mining plan in the expanded area will generally follow the steps already in use in the <br /> existing plan,with a few significant changes. Recent drilling has helped greatly in defining a larger area <br /> of extent and depth of the obsidian deposit currently being developed. The new plan will begin by <br /> further defining the areal extent of the economically mineable obsidian deposit. <br /> Under the 112c permit, nearly the entire affected area will be disturbed by various mining activities. <br /> Some areas will be disturbed during initial years of the mining stage (such as topsoil and overburden <br /> stockpiling), and other areas will be disturbed throughout mining. <br /> Expansion of Quarry Area:Strip Topsoil and Overburden <br /> The expansion of the quarry will proceed differently than the incremental way it has been done in the <br /> past. Under the existing 110 plan,topsoil and overburden are incrementally stripped and the highwall is <br />