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Table 1 is a design flow su~;•mary sheet for Lower Westmoreland Canyon. <br />• The flows were computed for nodes 1, 7, and 10 shown in Figure 6. Compu- <br /> tations for OPP peak floo-a are sur,zrized in Appendix I5' . Each node is a <br />control point where a hydraulic structure ~•:ould be required. Design floti•rs <br />for other locations in the watershed are presented elsewhere in the mine <br />plan. figure 6, Plate I and Plate II sho',: the configuration of ditches, <br />etc. that ~•rould be required to direct the surface runoff to each node. <br />It should be emehasized that runoff Generated from all disturbed areas '•~il <br />be routed thrcuoh sediment ponds (Plate II) in conformar~ce ~:ith CSt <br />renulations. <br />TABLE 1 <br />DESIGN FLO'+! SU•~~~P.Y SHEET - WESTt•~ORELAi;D CAt;YO~~ (see Appendix IY) <br /> <br />• ZO;;E <br />r;ODE <br />tv0. APPROX. <br /> <br />AP,EA <br />UPSTREAr•1 <br />(acres?1 GESIG'; ^":""-''r (r.f.s.) <br />- - <br />PR03A;.~- ' . ~0-7•EA°~- <br />NR Y,. (OPP) <br /> <br />REh'J~P.f;S <br />U?PER 6ASIN <br />DI':EP.SI0;1 -- DESIGt; FLO'~d: 550 c.f.s. <br /> 11 33.7 399 <br /> 12 50.6 590 <br />1~ 1 18.5 28 CN for 100-year storm = BO <br />2°- 7 18.3 26 <br />34 10 17.0 40(25)5 CN for 100-year storm = 80 <br />(OPP peak for C": 80 = 25 c.f. <br />~ Deterrr:ined frog configuration sho;,'n in Plate I. <br />Assumed runoff curve number (Cr;) = 75 for both Upper and Lower basins. <br />9 P.ecormended lo•,:er limit design storm (USDI, !1E SA, "Engineering and <br />Design t;anual--Coal Refuse Facilities," 1976). <br />. "- Floo-a computed assuming control of Upper basin runoff from PIfTS. <br />5 q = 25 c.f.s. (CN 80) at node 10 is believed to be sufficiently <br />p conservative for design. <br />