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embankment. The area is well vegetated and has crock-check dam, which will additionally filter surface runoffprior to
<br />• discharge.
<br />Overland Belt West - this area is comprised of some 0.5 acres between the haulroad embankment and railroad tracks
<br />west ofthe Hautroad C rail crossing. Estimated runoff for the 10 yrfZ4 hr event would be same 0.03 acre-feet from this
<br />area, and will be treated by means of a rock filter. This should be more than sufficient, given that drainage for the area
<br />is neazly static,
<br />Haulroad C to_psoil~ile -covets approximately 0.3 acres between the haulroad and Foidel Creek, and is located across
<br />from Pond C. Runoff from the area is filtered by established vegetative cover. TCC will also inscribe a bemt and install
<br />rock filters to further treat the anticipated 0.01 AF of ntnoff for the 10 yr/24 hr event from this area.
<br /># 7 North Esca__pe Shaft -covers 1.82 anus of disturbance and is located in the SE 1/4, Section 20, TSN, R86W, 6th
<br />P.M. on Cochetopa Loam (a C soil). SAE demonstrations have characterized four areas: the north outslope, the east
<br />and west outslopes, the south side of the topsoil pile, and the pad, which incorporates drainage from the north side of
<br />the topsoil pile, the cutslope, the berm, the pad, and road drainage from the road. Sediment control will be achieved by
<br />seeding and mulching the pad outslopes, the cutslopes, and the topsoil pile, and by placing strawbale dikes or a silt
<br />fence below each of these locations to prevent off-site migration of sediment prior to vegetative stabilization.
<br />Vegetative filters will provide adequate sediment detention to achieve effluent limitations following a 10-year 24-hour
<br />storm event for these locations. Rock check dams wilt be installed at the southeast corner of the topsoil pile and below
<br />a riprapped Swale descending the northeast corner of the outslope. Peak flows from a i 0-year 24-hour storm are 0.06
<br />cfs, 0.03 cfs, 0.42 cfs, and 1.59 cfs for the north outstope, east or west outslope, north side of the topsoil pile, and pad,
<br />respectively.
<br />EMD Ventilation Shaft -covers approximately 2.66 acres of disturbance and is located in the NW,SE, Sec. 14, TSN,
<br />• R86W, 6th P.M. on Routt loam (a C soil). SAE demonstrations have characterized three areas: the east side of the East
<br />topsoil pile; the south and west sides of the Southwest topsoil pile; and other topsoil slopes and the benches and cut and
<br />fill slopes of the facility itself. Sediment control will be achieved through the installation of an upland clean water
<br />diversion ditch that will not cant' any water from disturbed azeas, by seeding and mulching the topsoil piles and cut and
<br />fill slopes with 2 tons/acre straw and graveling the pads and roads with gravel adequate to achieve 80% cover.
<br />Vegetative filters will provide adequate sediment detention to achieve effluent limitations following a 10-year 24-hour
<br />stomr event. Peak flows from this storm are 0.05 cfs, 027 cfs, and ].96 cfs for the east side of the East topsoil pile, the
<br />south and wes! sides of the Southwest topsoil pile, other topsoil slopes, and the benches and cut and fill slopes of the
<br />facility, respectively.
<br />Pond T Toasoil Stockpile -covers some 0.5 acres between the Pond T embankment face and railroad spur. Runoff
<br />form this area flows downslope between the railroad embankment and Pond T face to the Pond T weir. From there,
<br />flow is conveyed under the track by means of a culvert to Foidel Creek. Vegetative filtering is provided by the
<br />establishment of good vegetation on the topsoil pile and in the conveyance below the topsoil stockpile. Additional
<br />filtering of sediment is provided by a rock filter between the stockpile and the culvert, benches, and cut and fill
<br />slopes of the facility itself. Sediment control will be achieved through the installation of an upland clean water
<br />diversion ditch that will not carry any water from disturbed areas, by seeding and mulching the topsoil piles and cut and
<br />fill slopes with 2 tonslacre straw and graveling the pads and roads with gravel adequate to achieve 80 % wver.
<br />Vegetative filters will provide adequate sediment detention to achieve effluent limitations following a 10-year 24-hour
<br />storm event. Peak flows from this storm aze 0.05 efs, 0,27 cfs, and 1.96 cfs for the east side of the Fast topsoil pile, the
<br />south and west sides of the Southwest topsoil pile, other topsoil slopes, and the benches and cut and fill slopes of the
<br />facility, respectively.
<br />
<br />APFP.~3~/a~i A°R 2 '[ 20Cii
<br />Permit Renewal No. 3 2.05-82 11/1199
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