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Table 8 Curve Numbers Provided in the SEDCAD model (from National Engineering <br />Handbook (NEH-4) (USDA-SCS, 1985), Continued <br />Runoff Curve Numbers for Other Agricultural Lands <br />Cover Type Hydrologic Condition A B C D <br />Pasture, grassland, or range-continuous Poor 68 79 86 89 <br />forage for grazing Fair 49 69 79 84 <br />Good 39 61 74 80 <br />Meadow - continuous grass, protected from 30 58 71 78 <br />razin and enerall mowed for ha <br />Brush -bnuh-weed-grass mixture, with Poor 48 67 11 83 <br />brush the major element Fair 35 56 70 77 <br />Good 30 48 65 73 <br />Woods - grass combination (orchard or tree Poor 57 73 82 86 <br />farm) Fair 43 65 76 62 <br />Good 32 58 72 79 <br />Woods Poor 45 66 77 83 <br />Fair 36 60 73 79 <br />Good 30 55 70 77 <br />Farmsteads - buildings, lanes, driveways, 59 74 82 86 <br />and surrounding lots <br />Notes: Values are for average runoff condition, and I, = 0.2S. <br />Pasture: Poor is < 50% ground cover or heavi ly grazed with no mulch, Fair is 50% to 75% <br />ground cover and not heavily grazed, and Good is >75% ground cover and lightly or only <br />occasionally grazed. <br />Meadow: Poor is <50% ground cover, Fair is 50% to 75% ground cover, Good is >75% <br />ground cover. <br />Woods/grass.. RC Ns shown were computed for areas with 50 percent grass (pasture) cover. <br />Other combinations of conditions may be computed from RCNs for woods and pasture. <br />Woods: Poor is forest litter, small trees, and brush destroyed by heavy grazing or regular <br />burning. Fair is woods grazed but not burned and with some forest litter covering the soil. <br />Good is woods protected from grazing and with litter and brush adequately covering soil. <br />Exhibit 7 Page 13 Revision Date: 6/19/09 <br />Revision No.: TR-73