The URL can be used to link to this page

Home My WebLink AboutSW4090301_401 Certification Application_20090519i 05-14-'09 09:26 FROM-Stimmel Asscoc, P.A. 3367615069 A� NCDENR T-011 P002/006 F-027 Permit Nvrn er:Sw'}lollo3al —M.ab (to be provided by OWQ) F whr�W STORMWATER MANAGEMENT PERMIT APPLICATION FORM 401 CERTIFICATION APPLICATION FORM BIORETENTION CELL SUPPLEMENT This form must be frlled out, printed and submitted. The Required Items Checklist (Part Ill) must be printed, filled out and submitted along with all of the required information. Project name Ivt 0D 66lds-King Contact name - ---- Phone number 336.723A067 Date FBtiruary 26, 2009... Drainage area number 1 Site Characteristics Drainage area 20,965 ft' Impervious area Percent impervious $9.0% Design rainfall depth Peak Flow Caiculalions Is prelp❑st control of the 1-yr, 24-hr peak flow required? :'",: Y. ' i. • (Y or N) 1-yr, 24-hr runoff depth ;:%: 3 in . 1-yr, 24•hr intensity ;0-21 inlhr Pre-tlevetopment 1-yr, 24-hr peak flow 2.Q$D. ft3lsec Post- development 1-yr, 24-hr peak flow ft'fsec Pre/Post 1-yr, 24-hr peak control -0.030 tt'lsee Storage Volume; Non -SA Waters Minimum volume required :::::1;5I4.0 ft3 Volume provided ::°':1,554.Q ft g OK Storageftume; SAWaters 1.5' runoff volume Pre -development 1-yr, 24-hr runoff Post -development 1-yr, 24-hr runoff Minimum volume required 0 ft, Volume provided fi3 Coll Dimensions Ponding depth of water 12 inches OK Ponding depth of water 1.00 ft Surface area of the top of the bioretendion cell 1,804.0 ft, OK Length; 54 It OK Width: 49 ft OK -or- Radius tt Media and Soils Summary Drawdown time, ponded volume 0.5 hr OK Dravdown time, to 24 inches below surface 12 hr OK Drawdown Time, total; 12.5 hr In -situ snit Soil permeability 2,00 inlhr OK Planting media sod. - Soil permeability 2,00 in/hr OK Soil composition % Sand (by weight) 85% OK % Fines (by weight) 10% OK % Organic (by weight) 5% OK Total: 100% Phosphorus Index (P-Index) of media 30 (uniuess) OK Form SW4o1-eioreNCAkiOn•Rev, 7 Parts I and 11. Dcsion Summary, Page 1 Of 2 05-14-'09 09:26 FROM-Stimmel Asscoc, P.A, 3367615069 T-012 P003/006 F-027 Permit Number: $ wy2191ca — '-1,16 (to be provided by DWQ) Basin Elevations Temporary pool elevation 1099.75 fmsi Type of Noretention cell (answer 'Y' to only one of the two following questions): Is this a grassed call? Y (Y or N) Is this a celt with t(eesishrubs? "N (YorN) Planting elevation (top of the mulch or grass sod layer) .'..1098.75 fmsI Depth of mulch :.:0 inches Bottom of the planting media soil 1096.75 fMSI Planting media depth 2 ft Depth of washed sand below planting media soil 0Mft Are underdrains being installed? (Y or N) How many clean oul pipes are being installed? What factor of safety is used for siziag, the underdrains? (See 10 BMP Manual Section 12.3.6) Additional distance between the bottom of the planting media and ft the bottom of the cell to account for underdrains Bottom of the cell required 1095.42 fmsI SHW7 elevation Distance from bottom to SKWT 15.42 ft OK Insufficient much depth, unless installing grassed cell. 102 MOL OK Planting Plan Number of tree species ... !,!o Number of shrub species ':74 Number of herbaceous groundcovet species Recommend more species Additional Information Does volume in excess of the design volume bypass the Y!.. (Y or N) bloretention cell? Does volume in excess of the design volume flow evenly distributed !:::.�' (Y or N) through a vegetated filter? What is the length of the vegetated filter`7 ft Does the design use a level spreader to evenly distribute flow? rl N (Y or N) Is the BMP located at least 30 feet from surface waters (50 feet if .:(YorN) SA waters)? Is the BMP located at least 100 feet from water supply wells? (Y or N) Are the vegetated side slopes equal to or k3ss than 371 ? Y or N) Is the BMP located in a proposed drainage easement with access to a public Right of Way (ROM? Inlet velocity (from treatment system) 0,46 fv= Is the area surrounding the cell likely to undergo development in N (Y or N) the future? Are the slopes draining to the bloretention cell greater than 20%? N (Y or N) Is the drainage area permanently stabilized? Y (Y or N) Pretreatment Used (Indicate Type Used with an "X' in the shaded cell) Gravel and grass (9-inchea gravel followed by 3-5 ft of grass) Grassed swale Forebay Other OK OK Show how flow is evenly distributed. OK OK OK OK OK OK OK OK Form sVV401,8icretan1jon-Rev.7 Parts I and it, Design Summary, Page 2 of 2 a 05-14-'09 09:27 FROM-Stimmel Asscoc, P,A, 3367615069 T-011 P004/006 F-027 Permit Number:__C'WH 09 t o of " AI oA (to be provided by DWQ) � or w"rFa HCDENR p STORMWATER MANAGEMENT PERMIT APPLICATION FORM 401 CERTIFICATION APPLICATION FORM BiORETENTION CELL SUPPLEMENT This form must he filled out, printed and submeed. The Required Items Checklist (Part !11) must be printed, filled out and submitted along with all of the required information. Project name Contact name Phone rumbei Date Drainage area number lien B1nht, 33b-723-1Q67 F&n' ",26, 2008 2 , .. t+ Bite Characteristics Drainage area ::iQ257 ft Impervious area :C8,7iti ftz Percent impervious 85.0% % Design rainfall depth :a,0 inch Peak How Calculations Is prelpasR control of the 1-yr, 24•hr peak flow required? ; Y ,:' '..:. (Y or N) 1•yr, 24-hr runoff depth :::i3 in 1-yr, 24-hr intensity ;`0:21 irAr Pre -development 1-yr, 24-hr peak flow ? 2,480'ft3lsec Post -development 1-yr. 24-hr peak Now 2:450. ft3lsec Pre/Post 1-yr, 24-hr peak control -0A34 015ec Storage Volume: Non -SA Waters Minimum volume required Votume provided 790,0 ft, OK Storage VolumoT 5A Waters 1.5' runoff volume ft3 Pre -development 1-yi, 24•hr runoff Post development 1-yr. 24-hr runoff Minimum volume required 0 fl' Volume provided ft3 —� Coll Dimensions Pondng depth of water 12 inches OK Ponding depth of water 1.00 ft Surface area of the top of the bioretention cell 925.0 It' OK Length, 40 ft OK Width: 29 ft OK -or- Radius ft Media and Soils Summary Drawdown time, ponded volume 0.5 hr OK Drawdown time, to 24 inches bakm surface 12 hr OK Drawdown time, total: 12.5 hr In -situ soil. Soil permeability 2.00 Whf OK Planting media soil, Soil permeability 2.00 inlhr OK Spil composition % Sand (by weight) 85% OK % Fines (by weight) 10% OK % Organic {by weight) 5% OK Tots}: 100°% Phosphorus Ir.dex (P-Index) of media 30 (uniltess) OK Form SY1401-Biorctemlion,Rev. 7 Pena i and 11. Design Summary, Page 1 of 2 �•. 05-14-'09 09:27 FROM-5timi Asscoc, P A 3367615069 T-011 P005/006 F-027 Permit Number.�`✓YO0 0/ (fo he provided by DW41 Basin Elevations Temporary pool elevation .1100.60 fmsl Type of bioretention cell (answer "Y" to only one of the two following questions): Is this a grassed cell? Y (Y or N) Is this a cell with treesishrubs? N (Y or N) Planting oievation (top of the mulch or grass sod layer) 1099,E fmst Depth of mulch . 0 inches Bottom of the planting media soil 1097.6 lmsl Planting media depth 2 ff Depth of washed sand below planting media soil 0.33 R Are underdrains being installed? Y (Y or N) Flow many clean out pipes are being installed? 2. What factor of safety is used for siting the underdrains? (See ;� p BMP Manual Section 12.3.6) Additional distance between the bottom of the planting media and the bottom of the cell to account for underdrains 1 Bottom of the cell required 1090.27 fmsl Si elevation 1U90 fmsl Distance from bottom to Si 16.27 ft OK Insuffident mulch depth, unless installing grassed cell. f0I. OK OK Planting Plan Number of tree species Number of shrub species : 0. Number of herbaceous groundcover speces".::. 1. Recommend more species. Additional Information Does volume in excoss of the design volume bypass the :..::...;: • (Y ar N) bioretention cell? Does volume in excess of the design volume flow evenly distributed ;' .'" through a vegetated filter? What is the length of the vegetated filter? ft Does the design use a level spreader to evenly distribute flow? N'' `1 • (Y or N) Is the GMP located at least 30 feet from surface waters (50 feet if : Y. (Y or N) SA waters)? . Is the BMP totaled at least 100 feet from water supply wells? . ` Y.;>.° . : ; (Y or N) Are the vegetated side slopes equal to or less than 3:1? :.' Y : i:..:..' (Y or N} is the BMP located in a proposed drainage easement with access Y.; (Y or N) to a public Right of Way (ROW)? Inlet velocity (from treatment system) .1.45 fUsac Is the area surrounding the cell likely to undergo development in ,N (Y or N) the future? .. Are the slopes draining to the bioretention cell greater than 20%? N. (Y or N) Is the drainage area permanently stabilized? Pretreatment Used (Indicate Type Used with an 'X' in the shaded cell) Gravel and grass (Binches gravel followed by 3-5 #t of grass) Grassed Swale Farebay Other OK OK Show how flow is evenly distributed. OK OK OK OK OK OK OK (Y or N) OK Form SW401•Riafetentlon-Rev.7 Parts i and II. Design Summary, Page 2 of 2