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. - February 27,1997 -3- 963-2178 TABLE 3 HYDROGRAPH RESPONSE SHAPE (HRS) .AND MAIOMUM (MAJQ LENGTHS OF OVERLAND FLOW Oak Bnuh, etc. M 300 M 300 Bare Soil (loose) M 300 F 300 Bare Soil (compacted handstands F 300 F 300 and roads) and vegetated azeas subject to disturbance by traffic Graveled Areas F 300 F 300 'HRS - M =Medium F =Fast TABLE 4 CONTROL PRACTICE FACTORS ;,:z=:.::;:,.:::;Walet~s6ed:Area:::::..:::.':;"::'; :.;;,;:' :.::::::::::.:: AcsesstnetiC::t':::' ::>.: ".':: ':":':"::;:Cotitcoi'PhaeEiee.Fsctoc:':':::: Cut Slopes Assessed as protected with Soil 0.03 Guard, considered conservative as field performance might approach 0.001 of better. Fill slopes and Topsoil Storage Pile Assessed as Hydromulched 0.64 slopes Seeded. Graveled roadways and bench or Gravel areas aze assessed as 0.05 pad surfaces providing 100% cover. For all sites, based on prior experience by MCC with BMP's for sediment control, sediment control will be accomplished using a combination of silt fences and straw bales. The vegetative filter was modeled to show that it can be an effective means of secondary sediment control. Neither silt fences nor straw bales are evaluated as contributing factors in the SAE effluent analysis, although in actual practice these structures will be used as the primary sediment control structures for the SAE's. Fill slopes are analyzed as seeded and mulched. Cut slopes are protected with Soil Guard (trade name of sprayed protective duff). SedCAD+ does not model vegetative (brush) litter as a filter. These structures were equated to grass filters. The natural vegetation of the sites is either open meadow or oak brush with chokecherry and serviceberry. There is a layer (minimum of 2 inches) of brush litter of the ground. However, flows and velocities are so low that the litter would probably remain stable and in place, or rapidly dam up in collections of debris. The ground cover (vegetative 8~61~\96LI]g~il"2EAn.LTR Golder QSSOCIdtBs