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<br />roadway which will be removed/covered by highwall work as described above. Approximately <br />three miles of roadway will remain within the affected land boundaries, utilized for site access <br />and maintenance of revegetated areas. These remaining roadways will be smaller (12-16' <br />widths) and as low a grade as possible for long term run off impact control. While the worth of <br />the equipment will far outmatch the cost of removal, for the purposes of this closure cost <br />estimate, no estimate of market value will be used to off-set the removal cost. <br />Estimate of removal of equipment, concrete structures, and roadways including all roadways not <br />removed by highwall work ......................... $25,000 <br />FINAL STORMWATER MANAGEMENT SITE CONFIGURATION <br />The present crusher site will be used for a large sediment pond structure that will effectively <br />control storm flows from more than 95% of the mine site. This is due to the crusher site location <br />at the lowest elevation and bottom of the haul road network prior to leaving the mining site. <br />After removal of mining equipment, gypsum stockpiles, and concrete structures, the present <br />crusher site area will be graded to form a large settling pond of three to four acre-feet of storage <br />prior to discharge of stormwater to the existing stormwater ditch and sediment pond system <br />installed in 1995. The discharge of the sediment pond will be designed to handle a 200 cfs <br />storm event. The gypsum rock stockpile on site may be used for the sediment pond embankment <br />if not marketed. Concrete structures may be used for spillway construction. The sediment pond <br />area will be planted to native grasses and shrubs and mulched in accordance with common <br />reclamation practices on the site, as the sediment control structure per se addresses a 100 year <br />storm event. The construction of the sediment pond embankment will consume about 15,000 <br />tons of material and cost an estimated $30,000.00 . <br />Above the existing crusher site, the rock talus/highwall reduction work will afford a large <br />amount of rock material which will be used to line all ditches and pathways of stormflow. <br />Blasted rock materials will be bulldozed to containment berms at the toe of all rock talus slopes <br />to slow stormwater velocities prior to moving downgrade towards the existing crusher site/large <br />sediment pond area. Finish grading and rip-rap placement along with final roadway <br />configuration will cost an estimated $25,000.00 in bulldozer and other machine time <br />REVEGETATION OF SPECIFIC AREAS <br />Sixty acres of the affected land is currently under some state of reclamation. Approximately <br />forty of these is in a state of reclamation development that should meet closure criteria, ie, the <br />sites reflect a stable, self-sustaining vegetative mode and long term hydrologic and safety <br />concerns have been adequately addressed. Twenty acres of mined land is under revegetation <br />that might be considered well along but not advanced enough to qualify for full reclamation <br />status without further vegetative efforts. This twenty acres includes those areas called the North <br />