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surface water flow to the south and eventually into the southern end of the mining area, <br />where it is directed into the lower pit area. Surface water does not collect in this area but <br />quickly percolates into the well-fractured carbonate bedrock. Collection and diversion of <br />all surface water flows into the marble pit from former underground metal mining <br />operations located above the mazble mining zone will help to mitigate any potential for <br />low pH water that might be sourced from old metal mine workings. 2) Highwall <br />stabilization work will include the removal and stockpiling of a topsoil horizon of from <br />one to five feet in thickness that occurs at the surface of the black altered quaztzite <br />located immediately west of the marble beds. These soils will be stockpiled in narrow <br />windrows on benches above the mining hghwall bench system for future use for planting <br />medium on the flat portions of the benches. A hghwall bench configuration will be <br />developed to facilitate safe mining practices of the marble bed directly below. Mine <br />benches thirty feet wide(at top) and forty feet vertical height will be bulldozed starting <br />300 feet above the present marble outcrop at the surface, allowing for safe removal of the <br />mazble bed. The outslope of the mine bench system will be designed to lie at angle of <br />repose for the two upper benches, resulting in bench width of app. 30' at the base of each <br />bench. At the time of excavation of the bottom of the first bench, an evaluation of rock <br />hardness and competency of the quartzite bedrock exposed will be performed for <br />weathering characteristics and geotechnical stability. (app. 40' below present elevation), <br />the results of which will determine final bench number(s) limits and design of outslope. <br />Depending on rock quality characteristics as benching proceeds downwazd, outslope of <br />the third, fourth, and possibly fifth mine bench maybe left at a steeper angle no greater <br />than 70 degrees. In the lower benches, it is planned to utilize the blue gray mazble as <br />bedrock outslope material. 3) Highwall development will then allow for safe mining of <br />the white mazble bed up to 250 feet lower than the original surface outcrop. Mazble <br />extraction will proceed using conventional drilling and blasting techniques, with front- <br />end loader and excavators used for rock removal after blasting to be transported directly <br />by loader or loaded into trucks for transport to a mobile crushing and screening unit <br />located in the immediate area neighboring the working face. Stacking conveyors will be <br />used to construct production stockpiles of various grade and size. All equipment will be <br />on site seasonally, no permanent process structures or equipment is planned. Blasting <br />production benches may vary in height from 20-30'. Individual production rounds of <br />white mazble may vary greatly due to grade control restraints, from a few hundred tons <br />per blast to a few thousand tons per blast. Blasting procedures employed on-site will <br />meet all MSHA requirements for storage and use, and the county/Forest Service roadway <br />will be blocked off prior to each production round. Current mine plan calls for <br />approximately 30000 tons per year of mazble mined and processed, although volumes <br />may increase in the future to 50000 tons per year. On average, it is anticipated that a <br />Stripping Ratio of 1:1, W:O, will be in affect for life of mine. <br />6 <br />