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339 <br /> Project Area Land Cover Characteristics <br /> TN TP Pre- Post- <br /> PROJECT AREA LAND COVERS EMC EMC Project Project <br /> (mg/L) (mg/L) Area (ft) Area (ft) <br /> Roof _ _ 1.18 0.11 72,700 <br /> Roadway 1.64 0.34 83,649 <br /> Parking/Driveway/Sidewalk 1.42 0.18 263,339 <br /> Protected Forest 0.97 0.03 271,533 <br /> Other Pervious/Landscaping 2.48 1.07 3,680,820 2,889,340 <br /> CUSTOM LAND COVER 1 <br /> CUSTOM LAND COVER 2 <br /> CUSTOM LAND COVER 3 <br /> LAND TAKEN UP BY SCM 1.18 0.11 100,259 <br /> LAND COVER AREA CHECK <br /> Net Change of Land Covers(ft): 791,480 <br /> Total Project Area Entered (ft): 3,680,820 <br /> Total Pre-Project Calculated Area (ft2): 3,680,820 <br /> Total Post-Project Calculated Area (ft): 3,680,820 <br /> Equations Used and Project Area Calculations <br /> SIMPLE METHOD StormwaterRunoff Volume Generated, V <br /> Runoff Coefficient,R v V= Pi* Rv* (P/12)*A <br /> Rv= 0.05+(0.009*1) where A= drainage area(ft) <br /> where I= percent impervious(%) Pj= fraction of rain events with runoff <br /> Average Annual Pollutant Load,L P= average annual rainfall depth(in) <br /> L= (Pi*Rv*(P/12)) *(C*A*2.72) <br /> where C= event mean concentration(mg/L) <br /> Pre-Project: Post-Project: <br /> A= 84.5000 ac A= 84.5000 ac <br /> P = 47.31 in. P = 47.31 in. <br /> V= 653023 ft3 V= 2331222 ft3 <br /> I = 0% 1 = 14% <br /> Rv= 0.05 R,= 0.18 <br /> Pj = 0.9 Pj = 0.9 <br /> CTN = 2.48 mg/L CTN = 1.61 mg/L <br /> CTP = 1.07 mg/L CTP= 0.37 mg/L <br /> LTN = 101.13 Ib/yr LTN = 234.15 Ib/yr <br /> LTP = 43.63 Ib/yr LTP= 54.43 Ib/yr <br />