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In support of this request, these areas have been surveyed and <br /> supporting calculations have been prepared, using the Universal <br /> Soil Loss Equation (USLE) . (Attachment A) . <br /> A comparison has also been made to a permitted outfall (016) as to <br /> the allowable contribution of total suspended solids (TSS) to <br /> waters of the state (i.e. applicable effluent limits) . Potential <br /> soil/sediment loss f�om any area for which a small area exemption <br /> is requested is far less than is allowable for effluent from this <br /> point source. (Attachment B) . <br /> Measures for sediment control have been taken for each area, as <br /> described below. <br /> 1. Southwest end of 13 Mine pad. <br /> This area is relatively flat, and measures .12 acre in size. <br /> Concrete slabs cover a portion of the area. There are concrete <br /> walls still standing at two locations on the perimeter of the area. <br /> The surrounding terrain is steep. It is likely that this <br /> relatively flat beach reduces flow velocity and has a net <br /> deposition of sediment from the steep hillside above, so this area <br /> actually has the effect of decreasing overall sediment levels in <br /> the runoff from the hillside. <br /> Routing flows to sediment ponds is infeasible at this location, as <br /> the existing sediment ponds are upslope, and the steep hillside of <br /> the surrounding terrain makes it infeasible to construct a pond or <br /> catchment basin. <br /> For that reason, Mid-Continent has constructed a berm around the <br /> perimeter of the area to contain runoff. The berm extends on <br /> either side of the concrete walls, essentially including them as <br /> part of the berm. <br /> 2. Outslope of rock tunnel pad. <br /> The outslope extends from a berm which borders the portal yard <br /> area, down to the stream buffer zone along Dutch Creek, and covers <br /> an area of .75 acre. <br /> The outslope has been vegetated, and we have re-seeded and mulched <br /> the area where growth has been sparse. A straw berm has been <br /> established at the base of the re-vegetated lower slope to control <br /> run-off while the vegetation is re-established. <br /> 3. Outer slope at southeast end of berm behind the bathhouse. <br /> The outer slope at the southeast end of the berm is .12 acre in <br /> size. The entire berm berm is . 21 acre, but the northernmost side <br /> drains to the preparation plant yard area, and then to the 001 <br /> series of sediment ponds, and a rock berm (to the south) separates <br /> 2 <br />