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permit and spill prevention containment and control plan associated with <br />the NPDES permit also dictate preventative and mitigation measures for <br />ensuring that all water Tearing the mine site meets applicable effluent limits. <br />There are no variances from the requirements of the Rules and Regulations <br />proposed at this time. Therefore, no specific findings regarding water <br />quality standazds have been made. <br />The Division has granted a small area exemption from use of sediment <br />ponds due to the limited size of the azea and due to the fact that ponds and <br />treatment facilities are not necessary for the drainage to meet the effluent <br />limitations of Rule 4.05.2 and applicable State and Federal water quality <br />standards for receiving streams, and also due to the fact that no mixing of <br />surface drainage with a discharge from underground workings will occur. <br />The small areas to be exempted are topsoil stockpiles along the Tie-Across <br />Haul Road. (4.05.2(3)(b)(i}). <br />B. Diversions and Conveyance of Overland Flow <br />Seneca Coal Company has permitted seven ephemeral stream channel <br />reconstructions on the reclaimed mine site; 005 Gulch, 005-E1, 006 Gulch, <br />006-NET, 006-NE2, OOb-E1 and 006-SET. Five of the drainages are located <br />in the south mine azea and two in the north area. The reclaimed drainages <br />have been designed to safely pass the 100-yeaz, 24-hour storm event and can <br />be located in Tab 22 of the permit application. <br />The average postmining stream gradients will have concave longitudinal <br />profiles which approximate the premising slopes. The premising and <br />postmining drainage azeas of the reclaimed channels are similaz in acreage <br />and slope. After the watershed has been graded and the location of the <br />drainage channel determined, the channel will be constructed to the <br />required shape. At first, the channel will be rmtopsoiled to allow for initial <br />stabilization and inspected for stability according to the rill and gully plan in <br />Tab 22. When the channels have been stabilized, they will be topsoiled and <br />vegetated. <br />Seneca Coal Company has permitted stock tanks in both the reclaimed <br />drainage channels at the Seneca II-W Mine and some existing culvert <br />outlets. The stock tanks will slow the peak runoff of precipitation events <br />and help to minimise erosion in the drainage channels. They will also act as <br />an additional alternate sediment control measures, minimizing the potential <br />for sediment from roads to be tamed off the permit site. These small tanks <br />will benefit both livestock grazing and wildlife utilization of the reclamation. <br />16 <br />