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HomeMy WebLinkAboutWPO202200020 Stormwater Management Maintenance Agree. 2023-01-13SHIMP ENGINEERING, P.C. Design Focused Engineering Stormwater Management Plan Calculation Packet 0 4 183 rtrgj23 AL Project Name: SOUTH PANTOPS DRIVE PARCEL 20R. Prepared by. Shimp Engineering P.C. Date: April 27, 2022 Revision date: January 11, 2023 Page I SHIMP ENGINEERING, P.C. Design Focused Engineering Table of Contents Cover Page Table of Contents Project Narrative Project Description SWM Quantity SWM Quality Pre -Development Stormwater Management Calculations: Pre -Development Drainage Area Map Pre -Development HydroCAD Analysis to outfall Pre -Development Time of Concentration Calculations Time of Concentration Nomographs Pre-DA & Post DA Post -Development Stormwater Management Calculations: Post -Development Drainage Area Map Post -Development HydroCAD Analysis to outfall. Post -Development Ditch & inlet Drainage Area Map Energy Balance Equation Flood protection compliance check Time of Concentration - TOC VDOT LD-204 VDOT LD-209 VDOT LD-268 SWM Quality Requirements: Post-Dev NEW VRRM Landuse Map NEW VRRM -Development Spreadsheet Independent Reports: Excerpt from NRSC Soils Report NOAA Precipitation Report Appendix A: Rip- Rap Calculation Page 2 SHIMP ENGINEERING, P.C. Design Focused Engineering January 10, 2023 Albemarle County, VA 401 McIntire Road Charlottesville, VA 22902 434-243-7929 djames2@albemarle.org albemarle.org Regarding: South Pantops Drive Parcel - 20R Stormwater Management Plan Proiect Description The purpose of this project at South Pantops Drive — Parcel 20R is to build a thirteen (13) Units townhouse development. All SWM calculations required are contained within the following report. The development property has an area of 5.34 acres and the development will disturb a total area of 1.10 acres. The proposed stormwater design meets water quality requirements set forth in 9VAC25-870-65 and water quantity requirements set forth in 9VAC25-870-66-B.(3) and 9VAC25-870-66-C(3)c SKM Quandtp The runoff from this development is released into the manmade channel in compliance with quality regulation detailed in 9vac25-870-66-b (channel protection) and 9vac25-870-66-c(3).c (flood protection): Channel protection: a portion of concentrated runoff flowing thru the site shall be routed via new storm drains into the natural channel which will release runoff at rates which comply with the energy balance equation 9vac25-870-66- b(3). Flood protection: to meet flood protection requirements our post -development run-off will be discharged into a channel thus, this is the limit of analysis and no further analysis is required. all channels to this point are adequate. regulation detailed in 9vac25-870-66-c(3).c SHW Quality 1. Per the NEW VRRM spreadsheet, no further total phosphorous treatment is required. 2. Water quality will be provided with dedication of 3.26 acres land into a swm forest/open space easement. 3. permeable pavement is utilized for run-off reduction and each driveway will be permeable pavement made of and interlocking pavers (IP). Each driveway will treat runoff from the front half of each townhouse. 4. concentrated runoff release to the outfall is contained within adequate manmade channel. Ref LD-268 ditch design analysis. Page 3 D&Siyn Fu o§ed 6Ryii5�g� fty Pre -Development Stormwater Management Calculations: Pre -Development Drainage Area Map Pre -Development HydroCAD Analysis to Outfall Time of Concentration Calculations Time of Concentration Nomographs Pre-Dev & Post-Dev Page 4 LEGEND hi PRE-DEV DA WOODS I� PRE-DEV DA TURF PRE-DEV DA IMPERVIOUS - WATER FLOW DIRECTIONAL ARROW --- LIMITS OF DISTURBANCE N:1119INKA.T_jjr•]jr_jq SHIHPENGINP lmI P.C. ENGINEERING-LANDPLANNING-PROJECT MANAGE10VT 200 0 200 400 600 PREDEV DRAINAGE MAP SOUTH PANTOPS DRIVE PARCEL 20R SCALE: 1 "=200' DATE: 16 APRIL 2022 REVISION DATE: 10 JANUARY 2023 Page 5 Pre -Development HydroCAD Report Pre Development A OFFSITE TO OUTFA L 3L • . 1 Subcat Reach Aon Llnk )evelopment TO OUTFALL Page 6 Pre Dev 1-10-2023 Prepared by {enter your company name here) Area Listing (all nodes) Area CN Description (acres) (subcatchment-numbers) 30.450 55 Woods, Good, HSG B (1S, 2S) 3.490 61 >75% Grass cover, Good, HSG B (1S, 2S) 18.320 98 Paved parking, HSG B (1S, 2S) 52.260 TOTAL AREA Pre —Drainage Areas Printed 1/11/2023 Page 7 Pre Dev 1-10-2023 Prepared by {enter your company name here) Soil Listing (all nodes) Area Soil Subcatchment (acres) Group Numbers 0.000 HSG A 52.260 HSG B 1S, 2S 0.000 HSG C 0.000 HSG D 0.000 Other 52.260 TOTAL AREA Pre —Drainage Areas Printed 1/11/2023 Page 8 Pre Drainage Areas Pre Dev 1-10-2023 Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Prepared by {enter your company name here} Printed 1/11/2023 HydroCAD® 9.10 s/n 07054 © 2010 HydroCAD Software Solutions LLC Page 4 Time span=0.00-60.00 hrs, dt=0.01 hrs, 6001 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S: Pre DevelopmentDA Runoff Area=51.540 ac 35.12% Impervious Runoff Depth=0.78" Tc=31.2 min CN=71 Runoff=29.47 cfs 3.340 of Subcatchment2S: Pre Development Runoff Area=0.720 ac 30.56% Impervious Runoff Depth=0.69" Tc=5.0 min CN=69 Runoff=0.87 cfs 0.041 of Link 3L: POA Inflow=29.60 cfs 3.381 of Primary=29.60 cfs 3.381 of Total Runoff Area = 52.260 ac Runoff Volume = 3.381 of Average Runoff Depth = 0.78" 64.94% Pervious = 33.940 ac 35.06% Impervious = 18.320 ac Page 9 Pre Dev 1-10-2023 Prepared by {enter y, company name here} Type 11 24-hr 1 yr, Pre Drainage Areas 24 hr Rainfall=3.03" Printed 1/11/2023 Summary for Subcatchment 1S: Pre Development DA OFFSITE TO OUTFALL Runoff = 29.47 cfs @ 12.30 hrs, Volume= 3.340 af, Depth= 0.78" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 18.100 98 Paved parking, HSG B 30.000 55 Woods, Good, HSG B 3.440 61 >75% Grass cover, Good, HSG B 51.540 71 Weighted Average 33.440 64.88% Pervious Area 18.100 35.12% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 31.2 Direct Entry, Time of Concentration Summary for Subcatchment 2S: Pre Development ONSITE TO OUTFALL Runoff = 0.87 cfs @ 11.97 hrs, Volume= 0.041 af, Depth= 0.69" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Descri 0.220 98 Paved parking, HSG B 0.450 55 Woods, Good, HSG B 0.050 61 >75% Grass cover, Good, HSG B 0.720 69 Weighted Average 0.500 69.44% Pervious Area 0.220 30.56% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Time of Concentration Summary for Link 3L: POA Inflow Area = 52.260 ac, 35.06% Impervious, Inflow Depth = 0.78" for 1 yr, 24 hr event Inflow = 29.60 cfs @ 12.30 hrs, Volume= 3.381 of Primary = 29.60 cfs @ 12.30 hrs, Volume= 3.381 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Page 10 Pre Drainage Areas Pre Dev 1-10-2023 Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Prepared by {enter your company name here} Printed 1/11/2023 HydroCAD® 9.10 s/n 07054 © 2010 HydroCAD Software Solutions LLC Page 6 Time span=0.00-60.00 hrs, dt=0.01 hrs, 6001 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S: Pre DevelopmentDA Runoff Area=51.540 ac 35.12% Impervious Runoff Depth=2.53" Tc=31.2 min CN=71 Runoff=108.76 cfs 10.878 of Subcatchment2S: Pre Development Runoff Area=0.720 ac 30.56% Impervious Runoff Depth=2.36" Tc=5.0 min CN=69 Runoff=3.16 cfs 0.142 of Link 3L: POA Inflow=109.16 cfs 11.020 of Primary=109.16 cfs 11.020 of Total Runoff Area = 52.260 ac Runoff Volume = 11.020 of Average Runoff Depth = 2.53" 64.94% Pervious = 33.940 ac 35.06% Impervious = 18.320 ac Page I I Pre Dev 1-10-2023 Prepared by {enter y, company name here} Type 11 24-hr 10 yr, Pre Drainage Areas 24 hr Rainfall=5.54" Printed 1/11/2023 Summary for Subcatchment 1S: Pre Development DA OFFSITE TO OUTFALL Runoff = 108.76 cfs @ 12.27 hrs, Volume= 10.878 af, Depth= 2.53" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 18.100 98 Paved parking, HSG B 30.000 55 Woods, Good, HSG B 3.440 61 >75% Grass cover, Good, HSG B 51.540 71 Weighted Average 33.440 64.88% Pervious Area 18.100 35.12% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 31.2 Direct Entry, Time of Concentration Summary for Subcatchment 2S: Pre Development ONSITE TO OUTFALL Runoff = 3.16 cfs @ 11.96 hrs, Volume= 0.142 af, Depth= 2.36" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Descri 0.220 98 Paved parking, HSG B 0.450 55 Woods, Good, HSG B 0.050 61 >75% Grass cover, Good, HSG B 0.720 69 Weighted Average 0.500 69.44% Pervious Area 0.220 30.56% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Time of Concentration Summary for Link 3L: POA Inflow Area = 52.260 ac, 35.06% Impervious, Inflow Depth = 2.53" for 10 yr, 24 hr event Inflow = 109.16 cfs @ 12.27 hrs, Volume= 11.020 of Primary = 109.16 cfs @ 12.27 hrs, Volume= 11.020 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Page 12 Pre Drainage Areas Pre Dev 1-10-2023 Type 11 24-hr 100 yr, 24 hr Rainfall= 9. 10 " Prepared by {enter your company name here} Printed 1/11/2023 HydroCAD® 9.10 s/n 07054 © 2010 HydroCAD Software Solutions LLC Page 8 Time span=0.00-60.00 hrs, dt=0.01 hrs, 6001 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S: Pre DevelopmentDA Runoff Area=51.540 ac 35.12% Impervious Runoff Depth=5.55" Tc=31.2 min CN=71 Runoff=242.32 cfs 23.827 of Subcatchment2S: Pre Development Runoff Area=0.720 ac 30.56% Impervious Runoff Depth=5.30" Tc=5.0 min CN=69 Runoff=6.98 cfs 0.318 of Link 3L: POA Inflow=243.17 cfs 24.145 of Primary=243.17 cfs 24.145 of Total Runoff Area = 52.260 ac Runoff Volume = 24.145 of Average Runoff Depth = 5.54" 64.94% Pervious = 33.940 ac 35.06% Impervious = 18.320 ac Page 13 Pre Dev 1-10-2023 Prepared by {enter y, company name here} Type 11 24-hr 100 yr, Pre Drainage Areas 24 hr Rainfall= 9. 10 " Printed 1/11/2023 Summary for Subcatchment 1S: Pre Development DA OFFSITE TO OUTFALL Runoff = 242.32 cfs @ 12.24 hrs, Volume= 23.827 af, Depth= 5.55" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Type II 24-hr 100 yr, 24 hr Rainfall=9.10" Area (ac) CN Description 18.100 98 Paved parking, HSG B 30.000 55 Woods, Good, HSG B 3.440 61 >75% Grass cover, Good, HSG B 51.540 71 Weighted Average 33.440 64.88% Pervious Area 18.100 35.12% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 31.2 Direct Entry, Time of Concentration Summary for Subcatchment 2S: Pre Development ONSITE TO OUTFALL Runoff = 6.98 cfs @ 11.96 hrs, Volume= 0.318 af, Depth= 5.30" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Type II 24-hr 100 yr, 24 hr Rainfall=9.10" Area (ac) CN Descri 0.220 98 Paved parking, HSG B 0.450 55 Woods, Good, HSG B 0.050 61 >75% Grass cover, Good, HSG B 0.720 69 Weighted Average 0.500 69.44% Pervious Area 0.220 30.56% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Time of Concentration Summary for Link 3L: POA Inflow Area = 52.260 ac, 35.06% Impervious, Inflow Depth = 5.54" for 100 yr, 24 hr event Inflow = 243.17 cfs @ 12.24 hrs, Volume= 24.145 of Primary = 243.17 cfs @ 12.24 hrs, Volume= 24.145 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Page 14 SOUTH PANTOPS DRIVE - PARCEL 20R Time of Concentration Calculations PREDEV TOC TO OUTFALL 100 ft Overland Flow 1.20% slope 0.35 C-value 11. 00 min Seelye Chart 1822.0 ft S.C. Flow 9.39% slope 2.15 fps velocity 14.12 min. NEH Figure 15-4 1081.2 ft Channel 88.0 ft height 5.48 min. Kirpich Chart TOC= 31.20 min. Poor Grass Surface Page 15 m 600 Soo Paved 400 e.e Bare 200 Soil 100 t FIBSS 90 Surface Dense 60 Glass 70 60 5o UC 30 p 10 TG = 0.225 L0.42 8-OA O C -1.0 Tc= 0w1gr.0 Flcm, Time, rwrps I. = t 4 gth of Shlt, rwl 35 6 - slep.. tsspfset C = Rawnal `C' Value... Graurb Character 1 30 0.9 0.8 0.7 0,6 W 0.3 0.2 \ \ �i z `O SOUTH PANTOPS DRIVE PRE & POST DEV TOC NOMOGRAPHS Tlmacac..ee.trad.. port" Nwnnnal F.ligimmedng HmdL:wk Figem lfH Velorld versus slope for shallow concentmled Now tan a.ao 0..70 0.60 25 a:0 n.nn aaa 11.60 min 0.20 POST TOC 20 F 11.60 min ? w PRE TOC z 0.10 u:ue Z 0.07 O w y 5 0.06 'S °� o.u6 a 1.0 w 5/ 0 ON 2.0 Oa / / Q 0.03 H 5.0 Lu W nz U � 00 U 20 0.01 10 ROT[CaV: "C" value fer Set-w Gearin, Ctaoro i,er 0. Gros. 0.215 f-." 0.25 a>sroes Gross Svfoce 0.[e 1 p posture 0•40 Bvs sot : O.fe Pawsu 0.90 OVERLAND FLOW TIME LEGEND TOC PRE TO POA -- -- OCPOST TOPOA TOC2 ASSUMED 5 MINUTES iiiiiiiiiiiiil�lr�l�l�iiiiiiiiiiiiiiiin�� ��������a111111111�1���YI���ar1� RIIllllr���� ■■■.1111111111111� ■■S�.»lllll� � �■■ ��■■■��■IIIIIIIIIII�■rI■It%4�11111111��■ �■■■■�1111111111 �■■■1111111111 II ,� �;�11%' I■IU%1�111lill�i�■■ Ilil;illlll■■1 IIIAIAII�■■ '. ■111111111��■ 111111111111MEN IIIIIIIIIIII■■_�_ -gym ======== : ...a.. �o ��■ mm ��■ :1 ��■ ■■ .......��� Ilmm��� IIIIIIIl�mm oil gw6- 2.15 FSP PRE TOC 2.15 FSP POST TOC V'eloclty(Ws) ' lc 16 4 F.mrarinns and mourptioas developed Rom flgum 154 Fluor type Depth m-ru:g'en Veluti[y equatiuw (ft) (Me) Pavement and xmell upland ymlliea 02 amr, V=2(1.329(a)" Gino .d watcrwgya 0.4 0.0FA1 Neard'bar, soduutlled(merlaad Now); and alluaial fans in western mountain 0.2 0.051 V-o.065(ey- ia,gkmis l'nlNvatM shai6ht rnw crops N2 0,0FiN Va8.762(iir. Start-A'asepasture 0.2 0.013 V-6.962(s)0.° Ainilnurealoes cultiya0on, contour or stnperoppe4 and woorllonds 0.2 0.101 V=6.03E(s)"' Forts with heavy grmmd lirrer and hay meadows 0.2 0.202 V=2.61f(s)- TOC NOMO LINE COLORS MATCH WITH NOTES IN TOC CALCS TRAVEL TIME FOR CHANNEL FLOW (Kilpich Chart) H (feet) 500 Tn (nin.) 5.48 MIN 5.48 MIN PRE TOC POST TOC ml 100 L (feet) 10000 pxd^Ole 50 50 5000 0 L rote: c c (1) For use with nature! chamels; w 10 (2) T r� ved m chaelar multiply w 300 to E F K ,yn £ 0 5 500 5 I Source: VDOT TIME OF CONCENTRATION OF SMALL DRAINAGE BASINS 1 Plate 5-3 Page 16 Post -Development Stormwater Management Calculations: Post -Development Drainage Area Map Post -Development HydroCAD Analysis to Outfall Post -Development Ditch & Inlet Drainage Area Map Energy Balance Equation Flood protection compliance check Time of Concentration VDOT LD-204 VDOT LD-209 VDOT LD-268 Page 17 LEGEND 002 POST-DEVDA WOODS POST-DEV DA TURF O® POST-DEV DA IMPERVIOUS POST-DEV DA BRUSH WATER FLOW DIRECTIONAL ARROW �IILIFA116Y91991&1111C7:19kilo] a ■■■■ POST-DEV DA TOTAL SHIMPENGINEERING, P.C. EN6INEERIN6-L410MNNN6-PRGIEff MANAGEENENT 7-5140 CHANLO.�ELE. �. z.... JUST OSHIME cNEE INGOO. 200 0 200 400 600 POSTDEV DRAINAGE MAP SOUTH PANTOPS DRIVE PARCEL 20R SCALE: 1 "=200' DATE: 16 APRIL 2022 REVISION DATE: 10 JANUARY 2023 Pe_e 18 Post -Development HydroCAD Report POST DA OUTF 9 Subcat Reach Aon Llnk A onsite VRRM :DUCTION Page 19 Post —Drainage Areas Post Dev 1-10-2023 Prepared by {enter your company name here) Printed 1/11/2023 Area Listing (selected nodes) Area CN Description (acres) (subcatchment-numbers) 0.130 48 Brush, Good, HSG B (2S) 30.000 55 Woods, Good, HSG B (1S) 3.440 61 >75% Grass cover, Good, HSG B (1S) 0.970 81 VRRM ADJUSTED CN (2S) 18.100 98 Paved parking, HSG B (1S) 52.640 TOTAL AREA Page 20 Post —Drainage Areas Post Dev 1-10-2023 Prepared by {enter your company name here) Printed 1/11/2023 Soil Listing (selected nodes) Area Soil Subcatchment (acres) Group Numbers 0.000 HSG A 51.670 HSG B 1S, 2S 0.000 HSG C 0.000 HSG D 0.970 Other 2S 52.640 TOTAL AREA Page 21 Post_Drainage Areas Post Dev 1-10-2023 Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Prepared by {enter your company name here} Printed 1/11/2023 HVdroCAD® 9.10 s/n 07054 © 2010 HVdroCAD Software Solutions LLC Page 4 Time span=0.00-60.00 hrs, dt=0.01 hrs, 6001 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S: POST DA offsite to Runoff Area=51.540 ac 35.12% Impervious Runoff Depth=0.78" Tc=31.2 min CN=71 Runoff=29.47 cfs 3.340 of Subcatchment2S: POST DA onsite VRRM Runoff Area=1.100 ac 0.00% Impervious Runoff Depth=1.09" Tc=5.0 min CN=77 Runoff=2.23 cfs 0.100 of Link 3L: POA Inflow=29.75 cfs 3.440 of Primary=29.75 cfs 3.440 of Total Runoff Area = 52.640 ac Runoff Volume = 3.440 of Average Runoff Depth = 0.78" 65.62% Pervious = 34.540 ac 34.38% Impervious = 18.100 ac Page 22 Post Dev 1-10-2023 Prepared by {enter your company name here} Post_Drainage Areas Type 11 24-hr 1 yr, 24 hr Rainfall=3.03" Printed 1/11/2023 Summary for Subcatchment 1S: POST DA offsite to OUTFALL Runoff = 29.47 cfs @ 12.30 hrs, Volume= 3.340 af, Depth= 0.78" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 18.100 98 Paved parking, HSG B 30.000 55 Woods, Good, HSG B 3.440 61 >75% Grass cover, Good, HSG B 51.540 71 Weighted Average 33.440 64.88% Pervious Area 18.100 35.12% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 31.2 Direct Entry, Time of Concentration Summary for Subcatchment 2S: POST DA onsite VRRM REDUCTION Runoff = 2.23 cfs @ 11.97 hrs, Volume= 0.100 af, Depth= 1.09" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Type II 24-hr 1 yr, 24 hr Rainfall=3.03" Area (ac) CN Description 0.970 81 VRRM ADJUSTED CN 0.130 48 Brush, Good, HSG B 1.100 77 Weighted Average 1.100 100.00% Pervious Area Tc Length Slope Velocity Capacity Description 5.0 Direct Entry, Time of Concentration Summary for Link 3L: PDA Inflow Area = 52.640 ac, 34.38% Impervious, Inflow Depth = 0.78" for 1 yr, 24 hr event Inflow = 29.75 cfs @ 12.30 hrs, Volume= 3.440 of Primary = 29.75 cfs @ 12.30 hrs, Volume= 3.440 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Page 23 Post_Drainage Areas Post Dev 1-10-2023 Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Prepared by {enter your company name here} Printed 1/11/2023 HVdroCAD® 9.10 s/n 07054 © 2010 HVdroCAD Software Solutions LLC Page 6 Time span=0.00-60.00 hrs, dt=0.01 hrs, 6001 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S: POST DA offsite to Runoff Area=51.540 ac 35.12% Impervious Runoff Depth=2.53" Tc=31.2 min CN=71 Runoff=108.76 cfs 10.878 of Subcatchment2S: POST DA onsite VRRM Runoff Area=1.100 ac 0.00% Impervious Runoff Depth=3.08" Tc=5.0 min CN=77 Runoff=6.23 cfs 0.282 of Link 3L: POA Inflow=109.50 cfs 11.161 of Primary=109.50 cfs 11.161 of Total Runoff Area = 52.640 ac Runoff Volume = 11.161 of Average Runoff Depth = 2.54" 65.62% Pervious = 34.540 ac 34.38% Impervious = 18.100 ac Page 24 Post Dev 1-10-2023 Prepared by {enter your company name here} Post_Drainage Areas Type 11 24-hr 10 yr, 24 hr Rainfall=5.54" Printed 1/11/2023 Summary for Subcatchment 1S: POST DA offsite to OUTFALL Runoff = 108.76 cfs @ 12.27 hrs, Volume= 10.878 af, Depth= 2.53" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 18.100 98 Paved parking, HSG B 30.000 55 Woods, Good, HSG B 3.440 61 >75% Grass cover, Good, HSG B 51.540 71 Weighted Average 33.440 64.88% Pervious Area 18.100 35.12% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 31.2 Direct Entry, Time of Concentration Summary for Subcatchment 2S: POST DA onsite VRRM REDUCTION Runoff = 6.23 cfs @ 11.96 hrs, Volume= 0.282 af, Depth= 3.08" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Type II 24-hr 10 yr, 24 hr Rainfall=5.54" Area (ac) CN Description 0.970 81 VRRM ADJUSTED CN 0.130 48 Brush, Good, HSG B 1.100 77 Weighted Average 1.100 100.00% Pervious Area Tc Length Slope Velocity Capacity Description 5.0 Direct Entry, Time of Concentration Summary for Link 3L: PDA Inflow Area = 52.640 ac, 34.38% Impervious, Inflow Depth = 2.54" for 10 yr, 24 hr event Inflow = 109.50 cfs @ 12.27 hrs, Volume= 11.161 of Primary = 109.50 cfs @ 12.27 hrs, Volume= 11.161 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Page 25 Post_Drainage Areas Post Dev 1-10-2023 Type 11 24-hr 100 yr, 24 hr Rainfall= 9. 10 " Prepared by {enter your company name here} Printed 1/11/2023 HVdroCAD® 9.10 s/n 07054 © 2010 HVdroCAD Software Solutions LLC Page 8 Time span=0.00-60.00 hrs, dt=0.01 hrs, 6001 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S: POST DA offsite to Runoff Area=51.540 ac 35.12% Impervious Runoff Depth=5.55" Tc=31.2 min CN=71 Runoff=242.32 cfs 23.827 of Subcatchment2S: POST DA onsite VRRM Runoff Area=1.100 ac 0.00% Impervious Runoff Depth=6.29" Tc=5.0 min CN=77 Runoff=12.30 cfs 0.577 of Link 3L: POA Inflow=243.77 cfs 24.403 of Primary=243.77 cfs 24.403 of Total Runoff Area = 52.640 ac Runoff Volume = 24.403 of Average Runoff Depth = 5.56" 65.62% Pervious = 34.540 ac 34.38% Impervious = 18.100 ac Page 26 Post Dev 1-10-2023 Prepared by {enter your company name here} Post_Drainage Areas Type 11 24-hr 100 yr, 24 hr Rainfall= 9. 10 " Printed 1/11/2023 Summary for Subcatchment 1S: POST DA offsite to OUTFALL Runoff = 242.32 cfs @ 12.24 hrs, Volume= 23.827 af, Depth= 5.55" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Type II 24-hr 100 yr, 24 hr Rainfall=9.10" Area (ac) CN Description 18.100 98 Paved parking, HSG B 30.000 55 Woods, Good, HSG B 3.440 61 >75% Grass cover, Good, HSG B 51.540 71 Weighted Average 33.440 64.88% Pervious Area 18.100 35.12% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 31.2 Direct Entry, Time of Concentration Summary for Subcatchment 2S: POST DA onsite VRRM REDUCTION Runoff = 12.30 cfs @ 11.96 hrs, Volume= 0.577 af, Depth= 6.29" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Type II 24-hr 100 yr, 24 hr Rainfall=9.10" Area (ac) CN Description 0.970 81 VRRM ADJUSTED CN 0.130 48 Brush, Good, HSG B 1.100 77 Weighted Average 1.100 100.00% Pervious Area Tc Length Slope Velocity Capacity Description 5.0 Direct Entry, Time of Concentration Summary for Link 3L: PDA Inflow Area = 52.640 ac, 34.38% Impervious, Inflow Depth = 5.56" for 100 yr, 24 hr event Inflow = 243.77 cfs @ 12.24 hrs, Volume= 24.403 of Primary = 243.77 cfs @ 12.24 hrs, Volume= 24.403 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs Page 27 Channel Protection: Energy Balance Equation with Run-on for OUTFALL SOUTH PANTOPS DRIVE - 20R 1 Yr, 24 Hr Storm Comparison Q 1post < Q i Pre, site ((RV t Pre, sae)/(RV 1 Post, Site))(I.F.) + Q t Pre, offsite ((RV 1 Pre, offsite)/(RV t Post, offsite)) LF. = 0.8 when LOD > 1 ac, I.F.=0.9 when LOD <_ 1 ac, I.F. = 1.0 when predev site is fully forested PreDev Site Fully Forested? = no I.F. = 0.8 Limits of Disturbance = 1.10 ac Onsite Offsite Pre Dev Area Onsite = 0.72 ac Pre Dev DA Offsite = 51.54 ac Post Dev Area Onsite = 1.10 ac Post Dev DA Of3Site = 51.54 ac Q t Pre, site = 0.87 cfs Q t Pre, otsre = 29.47 cfs RV i Pre, site = 0.041 of RV i Pre, ofste = 3.340 of RV i Post, site = 0.100 of RV i Post, oftite = 3.340 of Predev 1-yr Flow Rate Sum Qlpre,site +Qlpre,Offsite = 30.34 cfs Regulatory Maximum Postdev 1-yr Flow Rate Max Qipost <_ 29.76 cfs Achieved Design Postdev 1-yr Flow Rate Design Qipost = 29.75 cfs Energy Balance Equation Compliance Check: Achieved Notes: 1. The assumption in the calculation above is that the site equals the land -disturbing activity (LDA). The definition for "site' is not clearly defined in the regulations, but LDAs are defined as regulated. The water quantity criteria are applied to the site as per the regulations. This nuance can be addressed by a VSW authority on a case by case basis or as standard policy, although more stringent application of water quantity technical criteria should appear in local ordinances for locality V S W authorities. 2. This site discharges to an outfall within a natural channel. Since postdevelopment runoff to this outfall meets the energy balance equation, Channel Protection Requirements per 9VAC25-870-66-B.3.a are met, and channel protection requirements are satisfied. Page 28 Flood Protection: Peak Flow Rate in Channel in Mapped Floodplain for Site Outfall SOUTH PANTOPS DRIVE - 2011 10 Yr, 24 Hr Storm Comparison Site outfall in mapped floodplain? = yes Regulatory Maximum 10-yr Flow Rate Qtopre = Max Qmpost = 109.16 cfs Achieved Design Postdev 10-yr Flow Rate Design Qlopost = 109.50 cfs Flood Protection Compliance Check: Achieved Notes: 1. In this case, the site discharges to a mapped floodplain, per 9VAC25-870-66-C-3c. Since 10-year runoff is confined within the stormwater conveyance system to this point of discarge, flood protection requirements are met. Page 29 SOUTH PANTOPS DRIVE - PARCEL 20R Time of Concentration Calculations - TOC POSTDEV TOC TO OUTFALL 100 ft Overland Flow 1.20% slope 0.35 C-value 11.60 min Seelye Chart 1822.0 ft S.C. Flow 9.39% slope 2.15 f s velocity 14.12 min. NEH Figure 15-4 1081.2 ft Channel 88.0 ft height 5.48 min. Kirpich Chart TOC= 31.20 min. NOTE: Poor Grass Surface ( Nomographs) 0.36 Page 30 LEGEND POST-DEV DA WOODS - LIMITS OF DISTURBANCE POST-DEV DA TURF POST -DITCH DA TOTAL O® POST-DEV DA IMPERVIOUS POST -INLET DA TOTAL POST-DEV DA BRUSH ® POST -PERMEABLE PAVERS AREA i Scale: 1 "=50' V�� WOOD — y_ ---_ - _ A" / HSG: \B- ='------- ---- O -- - --------------_ O °O` O O O OO _- \\ —--------------"- O O °O OO O; no-orl- � OO G ••••• x • ,1 � �� � P1, • 11 1� 114 J j RMEABLE AVERS-" .`'- )W • J. _� �-- Inlet DA ,----- - `Ditch DA 03 AC ` PRESERVED - �y\fir �' ` ` •\ ��- ' �_ _ SLOPE ! _"-- I I 1`� `� `� \\\\ . �� � — �---�/__ __-- ____ 7i -A(-•fir --- ' �,� ' , I I I1 � �\ �\ \ \\ `\ . .� FLOODWAY ��,-` ��_----_---�= ----- p ��,'-� , `/ I� I \ \� \� `� \`•\\\EE \' I 50 DITCH & INLET DRAINAGE MAP SOUTH PANTOPS DRIVE PARCEL 20R SHIMPENGINEMY6,,P.C. DATE: 10 JANUARY 2023 EvcnmFExwc-LUDMIKINO-FR0JECTHffA0HEvr �H, LO.E �.E. V. 22902 . sr asPHONE: E 3'EE. G SOUTH PANTOPS DRIVE - PARCEL 20R LD-204 Stormwater Inlet Computations Inlets on Grade Only Sag Inlets Only z m v � m U �C iipp d a 0' a 2 C7 a. C7 F rn Ca e a Od U q 'i 1 2 3 5 6 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 (ft) (ac) (in/hr) (cfs) I (cfs) (cfs) 1 (10 1 (?) (?) (ft) (ft) 1 (cfs) I (cfs) (ft) 1 (ft) (ft) A4 DI-2 8- 0.40 0.87 0.35 4.00 1.40 0.000 1.40 0.015 0.020 0.054 0.083 0.18 - - 8.87 6.5 2.28 0.000 2.28 0.25 12.28 Page 32 SOUTH PANTOPS DRIVE - PARCEL 20R LD-229 STORM DRAIN DESIGN COMPUTATIONS From To Catch. Runoff hic Ace= ToC Total Total Up Dn Pipe hw Pipe Pipe Velocity Flow time Point Point Area Ccef AC AC IntensityFlow cfs invert Invert Len Sloe Diameter Capacity Inc ac min in�hr El El 11 % in cfs fUs min 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 *A4 A3 0A0 0.87 0.35 0.35 5.00 5.17 1.81 394.50 387.50 84.55 8.28% 15 20.14 10.17 0.02 *A3 A2 - - - 0.35 5.02 5.16 1.81 383.26 381.00 39.4 5.74% 15 16.77 8.93 0.03 *A2 Al 035 503 516 1.81 376.50 376.03 18.94 2.48% 15 11.02 6.63 0.04 Page 33 SOUTH PANTOPS DRIVE - PARCEL 20R Modified LD-268 Roadside and Median Ditch Design Form Dosing Storm Side Slope I Min. I Max n=0.015 Concrete 0.04 Ditch C A CA Toe I - lin 12 110 Q - tin Q2 010 A L :1 R Slope Slope Allowable Velocity 2-yr 10-yr Matting Type Freeboard Channel Designed Depth SF AC INCR ACC FVFt Ft/Ft -Velocity --Depth -Velocity --Depth 1 0.46 88370 2.03 0.93 0.93 1 5.0 1.0 5.17 6.81 0.93 6.12 11.81 3 3 0.23 0.34 10.0 17.25 1 0.34 8.55 0.68 EC-3 TYPE II 0.12 0.80 "Velocity calculations performed using maximum slope for this application "Depth calculations performed using minimum slope for this application "` Q2 & Q10 flow from hydroCAD Structure channel DA Page 34 SHIMP ENGINEERING, P.C. Design Focused Engineering SWM Quality Requirements: Post -Development New VRRM Landuse Map New VRRM Development Spreadsheet Page 35 LEGEND VRRM IMPERVIOUS VRRM TURF VRRM WOODS SWM FOREST / OPEN SPACE ElPOST-DEV DA BRUSH m i I I I PRESERVEb-- __ ---- --- -- — SLOPES 0 80 160 224 WOOD NEW VRRM - DRAINAGE MAP SOUTH PANTOPS DRIVE PARCEL 20R REVISION DATE: JANUARY 10 2023 ``_ --- _OP DR` E S p(ER 1��140SOVj_�6'� Fes. • TUR, . "\ F < IMPERVIOUS ` .. - - o LIMITS OF DISTURBANCE 1.10 ACRES SWM FOREST/ OPEN SPACE TO BE DEDICATED 3.26 ACRES 78,PARCEL RIVANNA RIVER ._� PRESERVED SLOPE SCALE: 1 DEQ Yodefo Rstrufibeduction Method New Developments plianre Spreadsheet-Verson3.0 C 2011 area Standards and SpedBcatlons 0 2013 Oraft BMP Standards and Specifications Project Name: South Pantop Drive-Parce120R Date: lanuary062023 BMP Design Specifications List. 2013 Draft Stilt & Specs Site Information Post -Development Project (Treatment Volume and Loads) land Cover (acres) NSolls BSolls Cscale DSoils Totals Forest/Open Space (acres)—undourbetl, prmened forestropen space or redbreast land 3.26 326 Managed Turl)acres) — disturbed, traded for am: nr ocherow but to be med/man. ed 0.51 0.51 Impervious Cover laves) D s9 0.59 -forest/Open Some cameos man be protected in accoNorue was the Minima Runoff peruaied Method 6.36 Constants Runoff CoefficienK (Rv) Annual Randall (inches) 43 ASons BSois eSoils DSoils Target Rainfall Faced (inches) 1.00 oresvopen spere 0.02 0.03 0,04 0.05 Total Phosphorus OP) EMC Imi 0.26 Managed Turf 0.15 OLD 0,22 025 Total Nitrogen (Tn) EMC(mg/Q 186 lmcervmus cover 0.95 0.95 0,95 095 Target TP load llb/acre/yr) 0.41 Pj (unless mrrectim f lea rl 0.90 F.mWD n Space Co., (a.,) 3.26 Trea(aere-a af) 0.0636 Treatment Volume (cubic het) 2,76D TP bad (lb/yr) 1.73 TN lead pbyr) 12.00 Informational FuralOnl Weighted RV)foreed) 0.03 %Forest 75% Managed Turf Cover)acres) 0.51 Weighted Rv )turf) 0.20 %Managed Turf 12% Impervious Cover (acres) 0.59 Rv)Imparn s) 0.95 %Impervious 16% Site Area (actual 4.36 Site Rv 0.17 data Inpr cells nsrnt values calalatloncelb Page 37 Drainage Area A A. OCK Stormwater Bert Management PraRices IRR = Runoff ReduEBonl Swl MeaSxemA bARMIG Or Remenl In DFU AIeIM Pen DNVALPmemrrtnmemvoL"T M UA A IItI z,zv P.1- ANG. ReeuenT COURRO1 NAGA .un C,N,Ma o—O ery • , , realnree V,I ... DATA am ma(F) R pn " Ah"meelNel eenlMeR RmDF vewme lKl SDw RMP eamrm vene.INel PLe.Pne,"a ANSI EMeeenl%1 r, P ,Uaaml NG e IIN PneGMmG NBy mma0 RemaniM Pn�nvu USE) aue.e, r.an mw E� Iryed� a. na,e n 5re U1 uilLRxsl >a. snipe uanremm CC Nx ilk ILRxxI xasmy mposue Np-P1 Alm—K Uo_Nl Sp_ED U. xel xx Dp-.1 x ssa nil 6m MI T. —1, Cs 961 21 n lrM Al mi.. .A.m.mxzlsx=TU .. :11 ...m All s.k AL- PAL Ass: mnaaNsolklYRe31 G realm. ulene S. Msw.enlsDRUW .1—INUID,chl h-nm RPem e. eu,m.n onispanl a —n""n 92 a. "on nls­eC _n mm CIf -PSI . C. UD,C—, xz D—Ul A- 10 ISDC wzl n m..m. m.. VDsaI 10 DD PC n Teed VC,t S.IK so 0 0 0 0 0 om nm om ACC_.awh TOTAL IMPERVIOUS COVER TEQUDI e M TOTALMANNAGEDMIRFARESTRAFreDlad EA. CK TER.ttRLL URNOFF REDUCTION IN D.A.AUII TOLkLPHOUNHORSUSAVAILABLEFOR REMOVAL AAIIX/y,l TOTAL PHOSPHORUS REMOVED WITH RUNOFF REDUCTO PRACQUES1. AAII!/ ,1 Tmu PxxsPHORUS MMAININGAFTERAPPLYING RUNOFF REDUCTION PRArnCESIN DAAUWQ11. SEEMMQWCITYEOMVSMA TRa EOa SITEEOMYOANEEE HULA ONS ...(ChRRI ss. [uamartewwmPxlsPznsl " " " " o so om om Aznmmmv.ewwmazlsDaral 0 0 0 0 0 xs 0m om 00x 0m TOCALIMPERVIOUS Dlatl� A TGPLL GTUREAREATREATEDIa� AREA CHECK. DR. TOTAL PHOSPHORUS REMDvu REQUIRED DX SITE UIN`yQ0 TOTAL PHOSPHORUS NALULABLE FOR REMOVAL IN AA::- COMPERESPHO AAO •1 TOTLL PHOSPHORUS AO •l AAllb/y, A1 TELL PHOSPHORUS REMAINING AFTER APPLYING AEG LOAD REDUCTIONS IN DA A UWQ AAa=mGRHwMDVEDwmwITE AAa4Y,1 EDTAL NITROGEN REMOVED IN DJ, A a WY,I UN-1 LAae A".Mea G.UN .ee av NE., e EMnenrylzl I m—a t,el Q.-UUO POUGARUEO OUG Am IS IS VIA TOTAL AAlxj xmmGEx MREovEDwllxwxQETRUNOFF REDUCTION RND.A.A ahlyA(a) SEE HER FEE OWllT'COMVLIANEE Tfla EOx ST. fALEULA THOSE IIAfmnNwn OMY) A.NYak leeanx Plan) lee RR) 11 ale"RRI e ITTRRI 13 eale"RRI MP IT. SRI Page 38 Ngkk Rianfl Ra....... MQVirginia Runoff Redunion MahM1 New Developmem CompliameSp¢adsand,-Vemion3.0 BMV Ceslpn Spetlfimnom 1.1 2U33 O¢ft .d, S Spa¢ SNe SUmnN1Y Proleet Ttle:SautM1Panmp Dm Parce12UR Ogre: lanuary062023 Total Rainfall= G inches Site land Cover Summary A cols B9WIs Br C is DSOIk Leak Marraral forest/Open (acres) O.DD D.N 0.. 3.2fi 75 Managetl Turf (acres) O.DD D.51 D.LU 0.. 0.51 ]2 Imce rviou s Cow r(acres) 0.. D.59 D.N 0.. a59 1a 6.36 0D SNe Tv and land Craver Nutrient Loads ne Rv 0.1] Tn ant Volume (Frrl 1 2.z60 TP lnad(lb/Yr) 1.z3 IT. Wad(Ibar) 12. Talal W Watl Reduction Required (I TP LauD REOU CLION NOT REQU I RED Site Complance Summary TOUT Ruroff Volume Red union its) 388 Ttla1 TP and reduction Achle¢d (lb/yr) 0.32 TWa1TR Wad Reduction Achieved lib/M 227 Remainiry Post Development TP Wad (lb/yQ lA2 Remaining Wad Reduction (IbIW) 0.00 Required "TARGET W REDUCTION EXCEEDED BY 0.37 LB/YEAR" L.A. DAB oAC DAD DAE Total fareat/Open(acres) OW D.W 0.. O.OD 0.. 0.00 Managetl Turt(anes) 039 D.W 0.00 O.OD 0.00 0.39 Impetuous Caver(scres) 0.58 D.W 0.00 o.OD 0.. 0.58 TWI Area(MMS) a.. a.. OJqI am am o.97 Drainage Area Compliance Su mmarv, DAA DAB DAC DAD DAE Total TP Wad Reduced lb r 0.32 D.W 0.. O.OD 0.. D.32 TN Wad Reduced (Ib/yr) 227 D.W 0.. O.OD 0.. 227 Drainage Area A Summary Wnd Wver3ummary A Soils B9alk C3s k DSOIl Total Mafraral forest/Open(acres) 0.00 O.OD D.Ltla0 0.. Managetl Tuff (acres) 0.00 0.39 O.N 0.. 0.39 an Impewio sCover(acres) 0.00 0.58 O.LU 0.. 0.58 60 0.97 BMP Selections Managed Tuf ImpnNom Co¢r TP Wad kom oowmkeam PrMI¢ C12rArea GeMArea BMPTmhn¢t Volume(ft') Upstream Un[naMtlItsei Wad to PnN¢pbs) TP gemoved (Ib/N) 1P Remalnlry (Ib/Yr) Treatmenito he (ayes) (ayes) Prxtl¢s(Ib) EmPloYed 3a. Pmaneable Pavemem an tivIX soi OSS 86213 O.OD am 0.32 032 Thai Wpewiona Waarrremed(-1 0.25 rwi nrtA¢a Treat: (acres) 0.. TOMi n Watl Reduce -Achieved in oA Ib 0.32 TmaITX Wad Reduction Achieved In DA (Ib/w) 2.22 L- earstum 2y 2rss l0yearYmm Target Rainfall Event(in) 1 3..3 3.66 5.54 Dralnage Areas 0.V ACN D¢Inage/ueaA Drainage AreaR onlnagefi-C Drainage ArtaD ominage Area Cal B3 0 0 0 0 RR(fts) 3P8 0 0 0 0 1-mr realm pedool RVIIRR(111 1.67 ON n0] ON OCO RR(.1.1 ].36 ON ran OW on nl ale. R1 0 O 0 0 .-year realm pedotl 1IM(.n) 1.99 ON n0] OW on RR(.aln) 1... ON ran OW on or a¢nW RI 0 O 0 0 10year Mum period -IM(.n) 3.6] ON n0] OW on RVwRRnas4nj 3.56 ON ran OW OCo m aa}mes B2 0 0 0 0 Page 39 snnmayPM Site Results (Water Quality Compliance) Area Checks D.A. A D.A. B D.A. C D.A. D D.A. E AREA CHECK FOREST/OPEN SPACE (ac) 0.00 0.00 0.00 0.00 0.00 OK. IMPERVIOUS COVER (ac) 0.58 0.00 0.00 0.00 0.00 OK. IMPERVIOUS COVER TREATED [ac) 0.25 0.00 0.00 0.00 0.00 OK. MANAGED TURF AREA (ac) 0.39 0.00 0.00 0.00 0.00 OK. MANAGED TURFAREATREATED(ac) 0.00 0.00 0.00 0.00 0.00 OK. AREA CHECK Site Treatment Volume (ft3) z,7so Runoff Reduction Volume and TP By Drainage Area RUNOFF REDUCTION VOLUME ACHIEVED (ft) 388 0 0 0 0 388 TP LOAD AVAILABLE FOR REMOVAL (Ib/yr) 1 1.43 0.00 0.00 0.00 0.00 1.43 TP LOAD REDUCTION ACHIEVED (Ib/yr) 0.32 0.00 0.00 0.00 0.00 0.32 TP LOAD REMAINING (Ib/yr) 1.12 0.00 0.00 0.00 0.00 1.12 NITROGEN LOAD REDUCTION ACHIEVED (Ib/yr) 2.27 0.00 0.00 0.00 0.00 2.27 Total Phosphorus FINAL POST -DEVELOPMENT TP LOAD (Ib/yr) 1.73 TP LOAD REDUCTION REQUIRED (Ib/yr) 0.05 TP LOAD REDUCTION ACHIEVED (Ib/yr) 0.32 TP LOAD REMAINING (Ib/yr): 1.42 REMAINING TP LOAD REDUCTION REQUIRED (Ib/yr): 0.00 ** ** TARGET TP REDUCTION EXCEEDED BY 0.37 LB/YEAR ** Total Nitrogen (For Information Purposes) POST -DEVELOPMENT LOAD (Ib/yr) 12.40 NITROGEN LOAD REDUCTION ACHIEVED (Ib/yr) 2.27 REMAINING POST -DEVELOPMENT NITROGEN LOAD (Ib/yr) 10.13 Page 40 SHIMP ENGINEERING, P.C. Design Focused Engineering Independent Reports: Excerpt from NRSC Soils Report NOAA Precipitation Report Page 41 a11,4 M M 1 ti }In Y Y `ll tLIA I"'40 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrGs.usda.govtwps/ portal/nres/main/soils/healthn and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https:Hoffices.sc.egov.usda.gov/locator/app?agency=nres) or your NRCS State Soil Scientist (http://www.nrGs.usda.govtwps/portal/nres/detail/soils/contactus/? cid=nres 142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require Page 43 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Page" Contents Preface.................................................................................................................... 2 How Soil Surveys Are Made..................................................................................6 SoilMap.................................................................................................................. 9 SoilMap..............................................................................................................10 Legend................................................................................................................11 MapUnit Legend................................................................................................ 13 MapUnit Descriptions........................................................................................ 14 Albemarle County, Virginia..............................................................................17 10—Ronda loamy sand, 0 to 2 percent slopes, frequently flooded.............17 12C—Catoctin silt loam, 7 to 15 percent slopes ......................................... 17 12D—Catoctin silt loam, 15 to 25 percent slopes ....................................... 18 12E—Catoctin silt loam, 25 to 45 percent slopes........................................19 13E—Catoctin silt loam, 25 to 45 percent slopes, very stony.....................20 2313—Yadkin clay loam, 2 to 7 percent slopes............................................21 23C—Yadkin clay loam, 7 to 15 percent slopes..........................................22 26133—Dyke clay loam, 2 to 7 percent slopes, severely eroded.................23 47D—Philomont sandy loam, 15 to 25 percent slopes ............................... 24 58C—Myersville silt loam, 7 to 15 percent slopes.......................................25 58D—Myersville silt loam, 15 to 25 percent slopes.....................................26 58E—Myersville silt loam, 25 to 45 percent slopes.....................................27 59C—Myersville very stony silt loam, 7 to 15 percent slopes ..................... 28 59D—Myersville very stony silt loam, 15 to 25 percent slopes ................... 29 59E—Myersville very stony silt loam, 25 to 45 percent slopes ................... 30 71 B—Rabun clay loam, 2 to 7 percent slopes ............................................ 31 71C—Rabun clay loam, 7 to 15 percent slopes..........................................32 71 D—Rabun clay loam, 15 to 25 percent slopes ........................................ 33 71 E—Rabun clay loam, 25 to 45 percent slopes ........................................ 34 72133—Rabun clay, 2 to 7 percent slopes, severely eroded ........................35 72C3—Rabun clay, 7 to 15 percent slopes, severely eroded ..................... 36 72D3—Rabun clay, 15 to 25 percent slopes, severely eroded ................... 37 72E3—Rabun clay, 25 to 45 percent slopes, severely eroded....................38 73C—Rabun clay loam, 7 to 15 percent slopes, very stony........................39 73D—Rabun clay loam, 15 to 25 percent slopes, very stony......................40 73E—Rabun clay loam, 25 to 45 percent slopes, very stony......................41 76—Dan River loam, 0 to 2 percent slopes, occasionally flooded .............. 42 79B—Meadowville silt loam, 2 to 7 percent slopes.....................................43 88—Udorthents, loamy, 2 to 25 percent slopes .......................................... 44 W—Water.................................................................................................... 44 Charlottesville City, Virginia.............................................................................46 48E—Philomont sandy loam, 25 to 45 percent slopes, very stony.............46 5513—Danripple loam, 2 to 7 percent slopes, rarely flooded.......................47 77—Dan River-Codorus complex, 0 to 2 percent slopes, occasionally flooded.................................................................................................. 48 91—Urban land...........................................................................................49 112D—Catoctin - Urban land complex, 15 to 25 percent slopes.................50 171C—Rabun - Urban land complex, 7 to 15 percent slopes.....................51 4 Page 45 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil -vegetation -landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 6 Page 46 Custom Soil Resource Report scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil -landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil - landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, day, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field -observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. 7 Page 47 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. Page 48 1.2C - ��.. 7�2E371D 7.1B 1D ; 71C 7. 71B b 7�1B 72B3-�.71�D 796� 72C3 91 71C 79B 2aB 79B 71C 4.� '.. 72C3 72B3 r 77 yyi76 12C 23Cr �"„ 23B •.B� ` °v.71B-'.'.�, 71E 79B 72D3" . 7e11D 23B-•' 71B 71C ' 796 <.�„ .4 58D ��. _� . 79B 1�', 71C* 12D 71D,: 23C' 71D _ .. ,. .1 12E �: �„ a.'-,!w . .ti..72B3 i P y 71:B_ ^ 7_1`C 58C1 W� 59E � 58E . • Yp3B' 71C 71D 7+1'B. ►'L y 88 h fit" t o 1 �E 71D 23C 73D 23B •• •. •236 ,. J 59D �' 77° a71D73D :'71.C884 •' -�71D 59C 72C3 73C ` - 13E 12E ,. W 19B t ....t�'•c v +...� 72D3 71D 23B 71 D 23� 71B 3B C ,.. . 23 23C 71C ✓"7}1:D�C 3� 71C 71-D 11210J)"23G 72D3;72C3,. MAP LEGEND Area of Interest (AOI) ❑ Area of Interest (AOI) Soils O Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features V Blowout ® Borrow Pit Clay Spot O Closed Depression Gravel Pit Gravelly Spot O Landfill ik Lava Flow Marsh or swamp Mine or Quarry O Miscellaneous Water O Perennial Water V Rock Outcrop + Saline Spot Sandy Spot 4W Severely Eroded Spot 0 Sinkhole Slide or Slip J, Sodic Spot Custom Soil Resource Report a Spoil Area Q Stony Spot Very Stony Spot Wet Spot 0 Other •� Special Line Features Water Features Streams and Canals Transportation .--r-r Rails ti Interstate Highways N US Routes - - Major Roads Local Roads Background . Aerial Photography III /e1»x0=1.Ill MAP INFORMATION The soil surveys that comprise your AOI were mapped at scales ranging from 1:15,800 to 1:24,000. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Albemarle County, Virginia Survey Area Data: Version 15, Sep 13, 2021 Soil Survey Area: Charlottesville City, Virginia Survey Area Data: Version 8, Sep 1, 2021 Your area of interest (AOI) includes more than one soil survey area. These survey areas may have been mapped at different scales, with a different land use in mind, at different times, or at different levels of detail. This may result in map unit symbols, soil properties, and interpretations that do not completely agree across soil survey area boundaries. Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jun 8, 2020—Sep 23, 2020 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background MAP INFORMATION displayed on these maps. As a result, some minor of map unit boundaries may be evident. 11 Page 50 Custom Soil Resource Report Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 10 Ronda loamy sand, 0 to 2 0.6 0.1% percent slopes, frequently flooded 12C Catoctin silt loam, 7 to 15 9.8 1.1% percent slopes 12D Catoctin silt loam, 15 to 25 7.3 0.8% percent slopes 12E Catoctin silt loam, 25 to 45 17.5 2.0% percent slopes 13E Catoctin silt loam, 25 to 45 45.7 5.1% percent slopes, very stony 23B Yadkin clay loam, 2 to 7 percent 79.7 8.9% slopes 23C Yadkin clay loam, 7 to 15 22.0 2.5% percent slopes 26133 Dyke clay loam, 2 to 7 percent 1.2 0.1% slopes, severely eroded 47D Philomont sandy loam, 15 to 25 0.4 0.0% percent slopes 58C Myersville silt loam, 7 to 15 0.9 0.1% percent slopes 58D Myersville silt loam, 15 to 25 4.3 0.5% percent slopes 58E Myersville silt loam, 25 to 45 9.5 1.1% percent slopes 59C Myersville very stony silt loam, 6.9 0.8% 7 to 15 percent slopes 59D Myersville very stony silt loam, 27.9 3.1% 15 to 25 percent slopes 59E Myersville very stony silt loam, 1.8 0.2% 25 to 45 percent slopes 71 B Rabun Gay loam, 2 to 7 percent 31.5 3.5% slopes 71C Rabun Gay loam, 7 to 15 116.7 13.1% percent slopes 71 D Rabun clay loam, 15 to 25 1932 21.6% percent slopes 71 E Rabun clay loam, 25 to 45 34.2 3.8% percent slopes 72133 Rabun clay, 2 to 7 percent 9.0 1.0% slopes, severely eroded 72C3 Rabun Gay, 7 to 15 percent 18.0 2.0% slopes, severely eroded 72D3 Rabun Gay, 15 to 25 percent 11.1 1.2% slopes, severely eroded 13 rage 51 Custom Soil Resource Report Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 72E3 Rabun clay, 25 to 45 percent slopes, severely eroded 0.3 0.0% 73C Rabun Gay loam, 7 to 15 percent slopes, very stony 0.6 0.1% 73D Rabun Gay loam, 15 to 25 percent slopes, very stony 14.3 1.6% 73E Rabun clay loam, 25 to 45 percent slopes, very stony 1.8 0.2% 76 Dan River loam, 0 to 2 percent slopes, occasionally flooded 8.0 0.9% 79B Meadowville silt loam, 2 to 7 percent slopes 41.5 4.6% 88 Udorthents, loamy, 2 to 25 percent slopes 82.1 9.2% W Water 17.4 1.9% Subtotals for Soil Survey Area 815.6 91.4% Totals for Area of Interest 892.8 100.0% Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 48E Philomont sandy loam, 25 to 45 percent slopes, very stony 6.1 0.7% 55B Danripple loam, 2 to 7 percent slopes, rarely flooded 6.9 0.8% 77 Dan River-Codorus complex, 0 to 2 percent slopes, occasionally flooded 29.9 3.3% 91 Urban land 5.2 0.6% 112D Catoctin - Urban land complex, 15 to 25 percent slopes 5.1 0.6% 171 C Rabun - Urban land complex, 7 to 15 percent slopes 24.0 2.7% Subtotals for Soil Survey Area 77.2 8.6% Totals for Area of Interest 892.8 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some 14 Page 52 Custom Soil Resource Report observed properties may extend beyond the limits defined for a taxonomic Gass. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha -Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The 15 rage 53 Custom Soil Resource Report pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha -Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. 16 Page 54 Custom Soil Resource Report Albemarle County, Virginia 10—Ronda loamy sand, 0 to 2 percent slopes, frequently flooded Map Unit Setting National map unit symbol: 2v7hn Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Ronda, frequently flooded, and similar soils: 85 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Ronda, Frequently Flooded Setting Landform: Flood plains Down -slope shape: Linear Across -slope shape: Linear Parent material: Sandy alluvium derived from igneous rock Typical profile Ap - 0 to 10 inches: loamy sand C1 - 10 to 43 inches: sand C2 - 43 to 79 inches: loamy sand Properties and qualities Slope: 0 to 2 percent Depth to restrictive feature: More than 80 inches Drainage class: Excessively drained Runoff class: Very low Capacity of the most limiting layer to transmit water (Ksat): High to very high (5.95 to 19.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: NoneFrequent Frequency of ponding: None Available water supply, 0 to 60 inches: Low (about 3.8 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 5w Hydrologic Soil Group: A Hydric soil rating: No 12C—Catoctin silt loam, 7 to 15 percent slopes Map Unit Setting National map unit symbol: 2xxxk 17 Page 55 Custom Soil Resource Report Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Catoctin and similar soils: 80 percent Estimates are based on observations, descriptions, and transacts of the mapunit. Description of Catoctin Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 5 inches: silt loam Bw- 5 to 18 inches: very channery silt loam C - 18 to 28 inches: extremely channery silt loam R - 28 to 79 inches: bedrock Properties and qualities Slope: 7 to 15 percent Depth to restrictive feature: 20 to 40 inches to lithic bedrock Drainage class: Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 5.95 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Low (about 3.4 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B Hydric soil rating: No 12D—Catoctin silt loam, 15 to 25 percent slopes Map Unit Setting National map unit symbol: 2yfhj Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days 18 Page 56 Custom Soil Resource Report Farmland classification: Not prime farmland Map Unit Composition Catoctin and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Catoctin Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 5 inches: silt loam Bw- 5 to 18 inches: very channery silt loam C - 18 to 28 inches: extremely channery silt loam R - 28 to 79 inches: bedrock Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: 20 to 40 inches to lithic bedrock Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 5.95 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Low (about 3.4 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 4e Hydrologic Soil Group: B Hydric soil rating: No 12E—Catoctin silt loam, 25 to 45 percent slopes Map Unit Setting National map unit symbol: 2xxxi Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Catoctin and similar soils: 75 percent 19 Page 57 Custom Soil Resource Report Estimates are based on observations, descriptions, and transects of the mapunit. Description of Catoctin Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 5 inches: silt loam Bw- 5 to 18 inches: very channery silt loam C - 18 to 28 inches: extremely channery silt loam R - 28 to 79 inches: bedrock Properties and qualities Slope: 25 to 45 percent Depth to restrictive feature: 20 to 40 inches to lithic bedrock Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 5.95 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Low (about 3.4 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7e Hydrologic Soil Group: B Hydric soil rating: No 13E—Catoctin silt loam, 25 to 45 percent slopes, very stony Map Unit Setting National map unit symbol: 2xxxm Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Catoctin, very stony, and similar soils: 75 percent Estimates are based on observations, descriptions, and transects of the mapunit. 20 Page 58 Custom Soil Resource Report Description of Catoctin, Very Stony Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 5 inches: silt loam Bw- 5 to 18 inches: very channery silt loam C - 18 to 28 inches: extremely channery silt loam R - 28 to 79 inches: bedrock Properties and qualities Slope: 25 to 45 percent Surface area covered with cobbles, stones or boulders: 1.5 percent Depth to restrictive feature: 20 to 40 inches to lithic bedrock Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 5.95 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Low (about 3.4 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7e Hydrologic Soil Group: B Hydric soil rating: No 2313—Yadkin clay loam, 2 to 7 percent slopes Map Unit Setting National map unit symbol: 2v7hx Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: All areas are prime farmland Map Unit Composition Yadkin and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. 21 Page 59 Custom Soil Resource Report Description of Yadkin Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile Ap - 0 to 4 inches: clay loam BA - 4 to 10 inches: clay loam Bt - 10 to 63 inches: clay C - 63 to 88 inches: clay loam Properties and qualities Slope: 2 to 7 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 8.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B Hydric soil rating: No 23C—Yadkin clay loam, 7 to 15 percent slopes Map Unit Setting National map unit symbol: 2v7hy Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Yadkin and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Yadkin Setting Landform: Hillslopes 22 Page 60 Custom Soil Resource Report Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile Ap - 0 to 4 inches: clay loam BA - 4 to 10 inches: clay loam Bt - 10 to 63 inches: clay C - 63 to 68 inches: clay loam Properties and qualities Slope: 7 to 15 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 8.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6e Hydrologic Soil Group: B Hydric soil rating: No 26133—Dyke clay loam, 2 to 7 percent slopes, severely eroded Map Unit Setting National map unit symbol: 2xxxr Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Dyke, severely eroded, and similar soils: 85 percent Estimates are based on observations, descriptions, and transacts of the mapunit. Description of Dyke, Severely Eroded Setting Landform: Fans Landform position (two-dimensional): Footslope Landform position (three-dimensional): Base slope Down -slope shape: Concave Across -slope shape: Convex 23 Page 61 Custom Soil Resource Report Parent material: Residuum weathered from greenstone Typical profile Ap - 0 to 8 inches: clay loam Btl - 8 to 43 inches: clay 2Bt2 - 43 to 79 inches: gravelly clay Properties and qualities Slope: 2 to 7 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: High (about 9.1 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B Hydric soil rating: No 47D—Philomont sandy loam, 15 to 25 percent slopes Map Unit Setting National map unit symbol: 2v7jb Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Philomont and similar soils: 75 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Philomont Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from granite and gneiss Typical profile Ap - 0 to 5 inches: sandy loam Bt - 5 to 79 inches: sandy loam 24 Page 62 Custom Soil Resource Report Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): High to very high (5.95 to 19.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 6.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7e Hydrologic Soil Group: A Hydric soil rating: No 58C—Myersville silt loam, 7 to 15 percent slopes Map Unit Setting National map unit symbol: kbcn Elevation: 280 to 2,380 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Myersville and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Myersville Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile H1 - 0 to 7 inches: silt loam H2 - 7 to 28 inches: silty clay loam H3 - 28 to 44 inches: silt loam H4 - 44 to 79 inches: bedrock Properties and qualities Slope: 7 to 15 percent Depth to restrictive feature: 40 to 60 inches to paralithic bedrock Drainage class: Well drained 25 Page 63 Custom Soil Resource Report Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 6.5 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B Hydric soil rating: No 58D—Myersville silt loam, 15 to 25 percent slopes Map Unit Setting National map unit symbol: kbcp Elevation: 300 to 1,460 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Myersville and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Myersville Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down -slope shape: Linear Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile H1 - 0 to 7 inches: silt loam H2 - 7 to 28 inches: silty clay loam H3 - 28 to 44 inches: silt loam H4 - 44 to 79 inches: bedrock Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: 40 to 60 inches to paralithic bedrock Drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 1.98 in/hr) Depth to water table: More than 80 inches 26 Page 64 Custom Soil Resource Report Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 6.5 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 4e Hydrologic Soil Group: B Hydric soil rating: No 58E—Myersville silt loam, 25 to 45 percent slopes Map Unit Setting National map unit symbol: kbcq Elevation: 330 to 1,280 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Myersville and similar soils: 80 percent Estimates are based on observations, descriptions, and transacts of the mapunit. Description of Myersville Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down -slope shape: Linear Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile H1 - 0 to 7 inches: silt loam H2 - 7 to 28 inches: silty clay loam H3 - 28 to 44 inches: silt loam H4 - 44 to 79 inches: bedrock Properties and qualities Slope: 25 to 45 percent Depth to restrictive feature: 40 to 60 inches to paralithic bedrock Drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 6.5 inches) 27 Page 65 Custom Soil Resource Report Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7e Hydrologic Soil Group: B Hydric soil rating: No 59C—Myersville very stony silt loam, 7 to 15 percent slopes Map Unit Setting National map unit symbol: kbcr Elevation: 440 to 1,790 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Farmland of statewide importance Map Unit Composition Myersville and similar soils: 85 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Myersville Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile H1 - 0 to 7 inches: silt loam H2 - 7 to 28 inches: silty clay loam H3 - 28 to 44 inches: silt loam H4 - 44 to 79 inches: bedrock Properties and qualities Slope: 7 to 15 percent Surface area covered with cobbles, stones or boulders: 7.0 percent Depth to restrictive feature: 40 to 60 inches to paralithic bedrock Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 6.3 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6s 28 Page 66 Custom Soil Resource Report Hydrologic Soil Group: B Hydric soil rating: No 59D—Myersville very stony silt loam, 15 to 25 percent slopes Map Unit Setting National map unit symbol: kbcs Elevation: 360 to 1.770 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Farmland of statewide importance Map Unit Composition Myersville and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Myersville Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down -slope shape: Linear Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile H1 - 0 to 7 inches: silt loam H2 - 7 to 28 inches: silty clay loam H3 - 28 to 44 inches: silt loam H4 - 44 to 79 inches: bedrock Properties and qualities Slope: 15 to 25 percent Surface area covered with cobbles, stones or boulders: 7.0 percent Depth to restrictive feature: 40 to 60 inches to paralithic bedrock Drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 6.3 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6s Hydrologic Soil Group: B Hydric soil rating: No 29 Page 67 Custom Soil Resource Report 59E—Myersville very stony silt loam, 25 to 45 percent slopes Map Unit Setting National map unit symbol: kbct Elevation: 360 to 1,620 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Myersville and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Myersville Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down -slope shape: Linear Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile H1 - 0 to 7 inches: silt loam H2 - 7 to 28 inches: silty clay loam H3 - 28 to 44 inches: silt loam H4 - 44 to 79 inches: bedrock Properties and qualities Slope: 25 to 45 percent Surface area covered with cobbles, stones or boulders: 7.0 percent Depth to restrictive feature: 40 to 60 inches to paralithic bedrock Drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 6.3 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7e Hydrologic Soil Group: B Hydric soil rating: No 30 Page 68 Custom Soil Resource Report 71 B—Rabun clay loam, 2 to 7 percent slopes Map Unit Setting National map unit symbol: 2xxyl Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: All areas are prime farmland Map Unit Composition Rabun and similar soils: 80 percent Estimates are based on observations, Description of Rabun descriptions, and transects of the mapunit. Setting Landform: Interfluves Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 6 inches: clay loam Bt - 6 to 48 inches: clay C - 48 to 79 inches: silty clay loam Properties and qualities Slope: 2 to 7 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat) (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Moderately high to high Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2e Hydrologic Soil Group: B Hydric soil rating: No 31 Page 69 Custom Soil Resource Report 71C—Rabun clay loam, 7 to 15 percent slopes Map Unit Setting National map unit symbol: 2xxyn Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Rabun and similar soils: 80 percent Estimates are based on observations, Description of Rabun descriptions, and transects of the mapunit. Setting Landform: I nterfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 6 inches: clay loam Bt - 6 to 48 inches: clay C - 48 to 79 inches: silty clay loam Properties and qualities Slope: 7 to 15 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat) (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Moderately high to high Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6e Hydrologic Soil Group: B Hydric soil rating: No 32 Page 70 Custom Soil Resource Report 71 D—Rabun clay loam, 15 to 25 percent slopes Map Unit Setting National map unit symbol: 2xxyk Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Rabun and similar soils: 75 percent Estimates are based on observations, Description of Rabun descriptions, and transects of the mapunit. Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down -slope shape: Linear Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 6 inches: clay loam Bt - 6 to 48 inches: clay C - 48 to 79 inches: silty clay loam Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat) (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Moderately high to high Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6e Hydrologic Soil Group: B Hydric soil rating: No 33 Page 71 Custom Soil Resource Report 71 E—Rabun clay loam, 25 to 45 percent slopes Map Unit Setting National map unit symbol: 2xxym Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Rabun and similar soils: 75 percent Estimates are based on observations, Description of Rabun descriptions, and transects of the mapunit. Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down -slope shape: Linear Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 6 inches: clay loam Bt - 6 to 48 inches: clay C - 48 to 79 inches: silty clay loam Properties and qualities Slope: 25 to 45 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat) (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Moderately high to high Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7e Hydrologic Soil Group: B Hydric soil rating: No 34 Page 72 Custom Soil Resource Report 72133—Rabun clay, 2 to 7 percent slopes, severely eroded Map Unit Setting National map unit symbol: 2xxyq Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Rabun, severely eroded, and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Rabun, Severely Eroded Setting Landform: Interfluves Landform position (two-dimensional): Summit Landform position (three-dimensional): Nose slope Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 4 inches: clay Bt - 4 to 48 inches: clay C - 48 to 79 inches: silty clay loam Properties and qualities Slope: 2 to 7 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B Hydric soil rating: No 35 Page 73 Custom Soil Resource Report 72C3—Rabun clay, 7 to 15 percent slopes, severely eroded Map Unit Setting National map unit symbol: 2xxys Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Rabun, severely eroded, and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Rabun, Severely Eroded Setting Landform: I nterfluves Landform position (two-dimensional): Shoulder Landform position (three-dimensional): Side slope Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 4 inches: clay Bt - 4 to 48 inches: clay C - 48 to 79 inches: silty clay loam Properties and qualities Slope: 7 to 15 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 4e Hydrologic Soil Group: B Hydric soil rating: No 36 Page 74 Custom Soil Resource Report 72133—Rabun clay, 15 to 25 percent slopes, severely eroded Map Unit Setting National map unit symbol: 2xxyp Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Rabun, severely eroded, and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Rabun, Severely Eroded Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down -slope shape: Linear Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 4 inches: clay Bt - 4 to 48 inches: clay C - 48 to 79 inches: silty clay loam Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6e Hydrologic Soil Group: B Hydric soil rating: No 37 Page 75 Custom Soil Resource Report 72E3—Rabun clay, 25 to 45 percent slopes, severely eroded Map Unit Setting National map unit symbol: 2xxyr Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Rabun, severely eroded, and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Rabun, Severely Eroded Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down -slope shape: Linear Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 4 inches: clay Bt - 4 to 48 inches: clay C - 48 to 79 inches: silty clay loam Properties and qualities Slope: 25 to 45 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7e Hydrologic Soil Group: B Hydric soil rating: No 38 Page 76 Custom Soil Resource Report 73C—Rabun clay loam, 7 to 15 percent slopes, very stony Map Unit Setting National map unit symbol: 2xxyw Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Rabun, very stony, and similar soils: 85 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Rabun, Very Stony Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 6 inches: clay loam Bt - 6 to 48 inches: clay C - 48 to 79 inches: silty clay loam Properties and qualities Slope: 7 to 15 percent Surface area covered with cobbles, stones or boulders: 1.5 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7e Hydrologic Soil Group: B Hydric soil rating: No 39 Page 77 Custom Soil Resource Report 73D—Rabun clay loam, 15 to 25 percent slopes, very stony Map Unit Setting National map unit symbol: 2xxyt Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Rabun, very stony, and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Rabun, Very Stony Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down -slope shape: Linear Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 6 inches: clay loam Bt - 6 to 48 inches: clay C - 48 to 79 inches: silty clay loam Properties and qualities Slope: 15 to 25 percent Surface area covered with cobbles, stones or boulders: 1.5 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7e Hydrologic Soil Group: B Hydric soil rating: No 40 Page 78 Custom Soil Resource Report 73E—Rabun clay loam, 25 to 45 percent slopes, very stony Map Unit Setting National map unit symbol: 2xxyv Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Rabun, very stony, and similar soils: 75 percent Estimates are based on observations, descriptions, and transacts of the mapunit. Description of Rabun, Very Stony Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down -slope shape: Linear Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile A - 0 to 6 inches: clay loam Bt - 6 to 48 inches: clay C - 48 to 79 inches: silty clay loam Properties and qualities Slope: 25 to 45 percent Surface area covered with cobbles, stones or boulders: 1.5 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7s Hydrologic Soil Group: B Hydric soil rating: No 41 Page 79 Custom Soil Resource Report 76—Dan River loam, 0 to 2 percent slopes, occasionally flooded Map Unit Setting National map unit symbol: 2v7jz Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Prime farmland if protected from flooding or not frequently flooded during the growing season Map Unit Composition Dan river, occasionally flooded, and similar soils: 75 percent Minor components: 5 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Dan River, Occasionally Flooded Setting Landform: Flood plains Down -slope shape: Linear Across -slope shape: Linear Parent material: Alluvium derived from igneous rock Typical profile A - 0 to 12 inches: loam Bw - 12 to 35 inches: silt loam C - 35 to 79 inches: silt loam Properties and qualities Slope: 0 to 2 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat) (0.57 to 1.98 in/hr) Depth to water table: About 36 to 60 inches Frequency of flooding: NoneOccasional Frequency of ponding: None Moderately high to high Available water supply, 0 to 60 inches: High (about 9.0 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2w Hydrologic Soil Group: B Hydric soil rating: No Minor Components Hatboro, occasionally flooded Percent of map unit: 5 percent Landform: Flood plains 42 page 80 Custom Soil Resource Report Down -slope shape: Linear Across -slope shape: Linear Hydric soil rating: Yes 79B—Meadowville silt loam, 2 to 7 percent slopes Map Unit Setting National map unit symbol: 2v7k1 Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: All areas are prime farmland Map Unit Composition Meadowville, occasionally flooded, and similar soils: 80 percent Estimates are based on observations, descriptions, and transacts of the mapunit. Description of Meadowville, Occasionally Flooded Setting Landform: Drainageways Landform position (two-dimensional): Footslope Landform position (three-dimensional): Head slope Down -slope shape: Concave Across -slope shape: Convex Parent material: Colluvium derived from igneous rock Typical profile A - 0 to 18 inches: silt loam Bt - 18 to 53 inches: silty clay loam 2C - 53 to 79 inches: gravelly clay loam Properties and qualities Slope: 2 to 7 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: NoneOccasional Frequency of ponding: None Available water supply, 0 to 60 inches: High (about 9.4 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2e Hydrologic Soil Group: B Hydric soil rating: No 43 Page 81 Custom Soil Resource Report 88—Udorthents, loamy, 2 to 25 percent slopes Map Unit Setting National map unit symbol: 2xxz3 Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Udorthents and similar soils: 85 percent Minor components: 5 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Udorthents Setting Landform: I nterfluves Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from granite and gneiss Properties and qualities Slope: 2 to 25 percent Depth to restrictive feature: More than 80 inches Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Minor Components Hatboro, occasionally flooded Percent of map unit: 5 percent Landform: Flood plains Down -slope shape: Linear Across -slope shape: Linear Hydric soil rating: Yes W—Water Map Unit Setting National map unit symbol: kbgk 44 Page 82 Custom Soil Resource Report Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Water: 100 percent Estimates are based on observations, descriptions, and transects of the mapunit. 45 Page 83 Custom Soil Resource Report Charlottesville City, Virginia 48E—Philomont sandy loam, 25 to 45 percent slopes, very stony Map Unit Setting National map unit symbol: 2v7jf Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Philomont, very stony, and similar soils: 75 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Philomont, Very Stony Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from granite and gneiss Typical profile Ap - 0 to 5 inches: sandy loam Bt - 5 to 79 inches: sandy loam Properties and qualities Slope: 25 to 45 percent Surface area covered with cobbles, stones or boulders: 1.5 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): High to very high (5.95 to 19.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 6.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7s Hydrologic Soil Group: A Hydric soil rating: No 46 Page 84 Custom Soil Resource Report 55B—Danripple loam, 2 to 7 percent slopes, rarely flooded Map Unit Setting National map unit symbol: 2v7js Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: All areas are prime farmland Map Unit Composition Danripple, rarely flooded, and similar soils: 90 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Danripple, Rarely Flooded Setting Landform: Stream terraces Landform position (three-dimensional): Tread Down -slope shape: Convex Across -slope shape: Linear Parent material: Alluvium derived from igneous rock Typical profile Ap - 0 to 7 inches: loam Bt - 7 to 42 inches: clay BC - 42 to 52 inches: clay loam C - 52 to 79 inches: sandy clay loam Properties and qualities Slope: 2 to 7 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat): Moderately low to moderately high (0.06 to 0.20 in/hr) Depth to water table: About 60 to 72 inches Frequency of flooding: Rare Frequency of ponding: None Available water supply, 0 to 60 inches: High (about 9.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2e Hydrologic Soil Group: C Hydric soil rating: No 47 page 85 Custom Soil Resource Report 77—Dan River-Codorus complex, 0 to 2 percent slopes, occasionally flooded Map Unit Setting National map unit symbol: 2v7k0 Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Prime farmland if drained and either protected from flooding or not frequently flooded during the growing season Map Unit Composition Dan river, occasionally flooded, and similar soils: 50 percent Codorus, occasionally flooded, and similar soils: 40 percent Minor components: 5 percent Estimates are based on observations, descriptions, and transacts of the mapunit. Description of Dan River, Occasionally Flooded Setting Landform: Flood plains Down -slope shape: Linear Across -slope shape: Linear Parent material: Alluvium derived from igneous rock Typical profile A - 0 to 12 inches: loam Bw - 12 to 35 inches: silt loam C - 35 to 79 inches: silt loam Properties and qualities Slope: 0 to 2 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: About 36 to 60 inches Frequency of flooding: NoneOccasional Frequency of ponding: None Available water supply, 0 to 60 inches: High (about 9.0 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2w Hydrologic Soil Group: B Hydric soil rating: No 48 Page 86 Custom Soil Resource Report Description of Codorus, Occasionally Flooded Setting Landform: Flood plains Down -slope shape: Linear Across -slope shape: Linear Parent material: Alluvium derived from igneous rock Typical profile A - 0 to 8 inches: silt loam BA - 8 to 16 inches: silt loam Bwl - 16 to 26 inches: silty clay loam Bw2 - 26 to 40 inches: silty clay loam Bw3 - 40 to 79 inches: silt loam Properties and qualities Slope: 0 to 2 percent Depth to restrictive feature: More than 80 inches Drainage class: Somewhat poorly drained Runoff class: Very high Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: About 8 to 18 inches Frequency of flooding: NoneOccasional Frequency of ponding: None Available water supply, 0 to 60 inches: High (about 11.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3w Hydrologic Soil Group: B/D Hydric soil rating: No Minor Components Hatboro, occasionally flooded Percent of map unit: 5 percent Landform: Flood plains Down -slope shape: Linear Across -slope shape: Linear Hydric soil rating: Yes 91—Urban land Map Unit Setting National map unit symbol: kbg5 Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days 49 Page 87 Custom Soil Resource Report Farmland classification: Not prime farmland Map Unit Composition Urban land: 85 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Urban Land Setting Landform: Interfluves Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Linear Across -slope shape: Linear Parent material: Residuum weathered from granite and gneiss Typical profile H1 - 0 to 6 inches: variable H2 - 6 to 79 inches: variable Properties and qualities Slope: 0 to 25 percent Depth to restrictive feature: 10 inches to densic material Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 13.04 in/hr) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 8s Hydric soil rating: No 112D—Catoctin - Urban land complex, 15 to 25 percent slopes Map Unit Setting National map unit symbol: 2r7b8 Elevation: 310 to 430 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Map Unit Composition Catoctin and similar soils: 55 percent Urban land: 40 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Catoctin Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex 50 Page 88 Custom Soil Resource Report Across -slope shape: Convex Parent material: Residuum weathered from greenstone Typical profile H1 - 0 to 5 inches: silt loam H2 - 5 to 18 inches: very channery silt loam H3 - 18 to 28 inches: extremely channery silt loam H4 - 28 to 79 inches: bedrock Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: 20 to 40 inches to lithic bedrock Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 5.95 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Low (about 3.4 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7e Hydrologic Soil Group: B Hydric soil rating: No 171C—Rabun - Urban land complex, 7 to 15 percent slopes Map Unit Setting National map unit symbol: 2gjh5 Elevation: 330 to 430 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Rabun and similar soils: 50 percent Urban land: 40 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Rabun Setting Landform: Interfluves Landform position (two-dimensional): Backslope Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from greenstone 51 Page 89 Custom Soil Resource Report Typical profile H1 - 0 to 6 inches: clay loam H2 - 6 to 48 inches: clay H3 - 48 to 79 inches: silty clay loam Properties and qualities Slope: 7 to 15 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6e Hydrologic Soil Group: B Hydric soil rating: No Description of Urban Land Setting Landform: I nterfluves Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Linear Across -slope shape: Linear Parent material: Residuum weathered from granite and gneiss Typical profile H1 - 0 to 6 inches: variable H2 - 6 to 79 inches: variable Properties and qualities Slope: 0 to 25 percent Depth to restrictive feature: 10 inches to densic material Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 13.04 in/hr) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 8s Hydric soil rating: No 52 Page 90 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep -water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nres.usda.govAvps/portal/ nres/deta i I/nations I/soi Is/?cid=n res 142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www. nres.usda.gov/wps/portal/nres/detail/national/soils/?cid=nresl42p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www. nres.usda.gov/wps/portal/nres/detail/national/soils/?cid=nres142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nres.usda.gov/wps/portal/nres/detail/soils/ home/?cid=nres 142 p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nres.usda.gov/wps/portal/nres/ detail/national/landuse/rangepasture/?cid=stelprd b1043084 53 Page 91 Custom Soil Resource Report United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nres.usda.gov/wps/portal/ nres/detail/soils/scientists/?cid=nres 142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. hftp://www.nres.usda.gov/wps/portal/nres/detail/national/soils/? cid=n res 142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/lnternet/FSE—DOCUMENTS/nrcsl42p2_052290.pdf 54 Page 92 NOAA Atlas 14, Volume 2, Version 3 Location name: Charlottesville, Virginia, USA* Latitude: 38.0341°, Longitude:-78.4532° Elevation: 399.9 ft** ' source: ESRI Maps A -- source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES G.M. Bonnin, D. Martin, B. Lin, T. Parcybok, M.Yekta, and D. Riley NOAA, National Weather Service, Silver Spring, Maryland PF tabular I PF graphical I Maps & aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)+ Average recurrence Interval (years) Duretion + z s +o zs so 1 100 oo zoo soo +000 -m 5in (0.3118-0392) (0.30 79A 466) (0.443-0.545) (0.497--0 613) (0.557-0687) (0.603-0.746) (0.645-0.802) (0.682-0854) (0.724-0 919) (0.78-0 974) 0.564 23 3 +0-min (0.508-0626) (0.606A.2745) (0.709-0873) (0.795-0980) (0.888-1310) (0.96-1.19) (1.02127) (1.08-135) (1. 5-145) 1 (1: 91..53) 0.706 0.844 1. +5-min (0.35-0..783) (0.762-0937) (0. 977-1610) (1.011224) : (13-21639) (1.22-31751) (1.291..61) (1.0-515.71) (1.4411..83) (1.50.�93) 30-min (0.8704607) 1 (1.05-1.29) 1 (1.274257) 1 (1.46- .80) 1 (1.67-2606) (1.83-2..27) (1.8-2.47) (2. 2-2.66) (2.30-22..91) (24 3-3.12) 4.11 60-min (1.09i34) (1.3�62) (1.63-2.01) (1.90.2.34) (2.22�74) (2. 839.07) (27 3-3.40) (2. 8-3.73) (3. 9�818) (3.544.55) 3.07 6.47 2-hr 3894) (1.27-1.66) (1.542.0) (19 3-2.50) (2.27�93) (26 83.48) (3. 3 (3.37-4A2) (3. 3-4591) (a. 0---5.60) (45 96.20) 3-hr (1.391..82) (1.68-2.20) (2.0-2.76) (2.45-3.22) (2.91-3.83) (3.9�734) (3.67-4.87) (4.05-5.43) (4.576.20) (4.996.86) 6-hr (17 92.29) (2.176) (2.66-3.43) (3.124.3) (3.734.84) (4. 55753) (4.77 628) (5.32-7808) (6.09 8822) (6.749.23) 3 9 85 11.2 +2-hr (22 42.90) (2. 9-3.50) (3.34-4.35) (3.95-5.15) (4.7".24) (5A7- 7..22) (68.27) 2 0. (6.99 9343) (8.2) (9.09-2.7) 24-hr (2.72 3340) (3. 9-4612) (4. 9--0 5..26) )(4.946.20) 5.54 (6. 38.59) (6.95---8..79) (7.94-0.1) 11 (9.M.6) (10b- 3.8) (11.8-15.7) 2-0ey (32 0-3.99) (3. 9-4384) (4. 3515) (57 8-7.22) (6.99-8.77) (7. 8-0160.1) (9.04-131.5) (102- 3.1) (11.8- 5.4) (13.1-1 3) 3-0ey (3.454.21) (4. 85.11) (5. 0�49) (6.22$$61) (7.52924) (8. 8--010.6) (9.72- 2.1) (10.9- 3.7) (12� 6.2) (14116- 8.2) 4-day 7 0. (34.44) (4.475.37) 86 (5. .82) (6.65-8.0) (8.059671) (9.19-121.2) (10.4-2.7) (11.73--14A) (13.5- 6.9) (15.0. 9.1) 8.6 7-day (4.3165.11) (5. 96.16) (6A7-07..70) (7.528?96) (9. 080.8) (102- 2.3) (11.5-13.9) (12 .7) (1470- 8.3) (162- 0.4) 10dey (4.91575) (5.96.90) (7.278852) (8.379.84) (9.91--111.7) (11.1213.2) (12.414.8) (138--16.6) (15.6-19.0) (17.1---21.1) 2 17.7 921.3) 20 dey (6.53- .47) p. 0-8.91) (9.41--10.8) (107- 2.2) (12.3-14.2) (13.6- 5.7) (15.0.17.4) (16.3- 9.0) (181 (19.4-3.1) 30 dey (8.06-9.11) (9.55-10.8) (11.3-2.8) (12.6-14.3) (14.3-16.2) (15.6-17.7) (16.8 9.2) (18.0- 0.6) (19572.6) (207?24.1) as -day (101U 1.3) 1 (11.9-13.4) 1 (13.9- 5.6) 1 (15.417.3) 1 (173- 9.5) 1 (187021.1) 1 (20.0. 2.7) (21.3-24.2) (2?9-5.2) (24.0.27.7) 60-day 73 (11.9-13.2) (14.0-15.6) (16.1- 8.0) (1778- 9.8) (1927---22.1) (212? 3.7) (22.6- 5.4) (239-25.0) (25z5- 9.0) (26720.5) 1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atias 14 document for more information. Back to Top PF graphical Page 93 SHIMP ENGINEERING, P.C. Design Focused Engineering Appendix A: Rip -Rap Calculations Page 94