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HomeMy WebLinkAboutSW3221007_Design Calculations_20230203DOLLAR GENERAL — STORE #24556 HYDROLOGIC AND HYDRAULIC ANALYSIS REPORT BREC Prepared By: Prepared For: Project Site: BREC, P.A. Teramore Development, LLC TBD Briggs Road 1520 Meadowview Drive Joe Strickland, Dir. of Ops., NC Salisbury, NC 28146 Wilkesboro, NC 28697 214 Klumac Rd., Ste. 101 NCBELS Firm #C-3448 Salisbury, NC 28144 (336) 844-4088 (704) 224-7364 justin@brec.biz jstrickland@teramore.net 2 February 2023 CARD Ali�ss,o-<i,L SEAL = 035736 = Justin Church, PE Principal Engineer BREC, P.A. Dollar General — Store #24556 1 Table of Contents 1.0 General Information........................................................................................4 2.0 Methodology...................................................................................................4 2.1 Rainfall Data 4 2.2 Time of Concentration Calculations 2.3 Runoff Coefficient Calculations 2.4 Pipe Design 2.4.1 Outlet Design 2.5 Hydrology Calculations 2.5.1 Modified Curve Number Calculations 2.6 Infiltration Basin Design 2.6.1 Stage Storage 2.6.2 Anti -floatation Calculations 4 5 7 7 8 8 9 9 10 3.0 Results ..........................................................................................................11 Appendix.............................................................................................................12 Post -construction Design Storm Post -construction 10 Year, 24 Hour Post -construction 100 Year, 24 Hour Soils Report Infiltration Report List of Figures Figure 1 - System Storage of Design Storm.......................................................11 List of Tables Table 1 - NOAA Rainfall Depths...........................................................................4 Table 2 - NOAA Rainfall Intensity.........................................................................4 Table 3 - Post -Construction ToC...........................................................................5 Table 4 - Curve Numbers......................................................................................5 Table 5 - Post -Construction Drainage Areas........................................................6 Table 6 - Composite Rational Coefficients............................................................6 Table 7 - Pipe Design Summary ...........................................................................7 Table 8 - Riprap Outlet Stone Sizing.....................................................................7 Table 9 - Riprap Apron Dimensions......................................................................8 Table 10 - Modified SCS Curve Numbers.............................................................9 BREC, P.A. Dollar General — Store #24556 V Table 11 — Infiltration Basin Stage Storage Table...............................................10 Table 12 - Pipe Design Table.............................................................................12 BREC, P.A. Dollar General — Store #24556 3 1.0 General Information This document contains hydrologic and hydraulic calculations demonstrating compliance with post -construction state and local stormwater regulations for the construction of a 10,640 ft2 Dollar General retail store at the intersection of NC Hwy 150 and Briggs Road in Salisbury, NC. Specifically, regulations for this area require water quality treatment of the first flush (1") storm. The subject tract is composed of vacant agricultural field. No jurisdictional features are present on the site. The site is entirely composed of LdB2 soils which are hydrologic soil group B. Post construction stormwater requirements will be satisfied with an above ground infiltration basin which is approved by NCDEQ as a primary stormwater control measure. 2.0 Methodology Six post -construction drainage areas covering the subject tract improvements were identified. See plansheets for delineation. All proposed impervious areas are routed to the infiltration basin for treatment prior to discharge. 2.1 Rainfall Data Rainfall data was taken from NOAA Atlas 14, Volume 2, Version 3 for Salisbury, NC. Rainfall depths for each design storm are summarized below. Table 1 - NOAA Rainfall Depths Storm Rainfall Depth in First Flush 1.00 1 Year, 24 Hour 2.73 100 Year, 24 Hour 7.13 in hr 7.00 To„ = 0.828(Lo„N)o.46�So o.z3s (min) (Kerby) Lo„ = Overland flow length (f t) N = Retardance coefficient (dimensionless) So„ = Average surface slope (f t/ f t) Tch = 0.0078L°h 7S�h .ass (min) (Kirpich) Lch = Channel flow length (f t) Soh = Average channel slope (f t/ f t) All areas less than or equal to 0.5 acres were assigned a minimum time of concentration of 5 minutes. Table 3 - Post -Construction ToC Name Tov Tch Tc—talc min Tc—assumed min GROUND COVER For post -construction drainage areas, the composite curve number is calculated as: BREC, P.A. Dollar General — Store #24556 5 min min POST-CON:1 - - - 5 POST-CON:2 - - - 5 POST-CON:3 - - - 5 POST-CON:4 - - - 5 POST-CON:5 - - - 5 POST-CON:6 - - - 5 HSG B CN C IMPERVIOUS 98 0.95 GRASS 61 0.20 WOODED 55 0.15 CNcomppost - (Aiml�post x CNimp + Agrass x CNgrass + Awooded X CNwooded) Atotalpost Table 5 - Post -Construction Drainaae Areas Name HSG Outfall Atotal (acres) 'gimp (acres) Agrass acres Awooded (acres) CN comppost POST-CONA+ B 1 0.25 0.25 0.00 0.00 98.0 POST-CON:2+ B 1 0.23 0.22 0.01 0.00 96.8 POST-CON:3+ B 1 0.15 0.15 0.00 0.00 97.2 POST-CON:4+ B 1 0.16 0.16 0.00 0.00 98.0 POST-CON:5+ B 1 0.04 0.00 0.03 0.00 65.8 POST-CON:6+ B 1 0.25 0.00 0.25 0.00 61.0 TOTAL 1 1.08 0.78 0.29 1 0.001 87.9 SUBTOTAL+ TO SCM 1.081 0.78 0.29 1 0.001 87.9 + Routed through stormwater control measure prior to discharge. A composite rational calculated for each conveyance sizing. runoff coefficient and associated discharge was also post -construction drainage area for pipe and swale Aimppost x Cimp + Agrasspost x Cimp + Awoodedpost x Cwooded Ccomp = Atotalpost Q = CcomplA Table 6 - Composite Rational Coefficients Name Atotal (acres) Aimp (acres) Agrass (acres) Awooded (acres) Ccomp t3 Q f- s POST-CONA* 0.25 0.25 0.00 0.00 0.95 1.66 POST-CON:2* 0.23 0.22 0.01 0.00 0.93 1.49 POST-CON:3* 0.15 0.15 0.00 0.00 0.93 0.98 POST-CON:4* 0.16 0.16 0.00 0.00 0.95 1.05 POST-CON:5* 0.04 0.00 0.03 0.00 0.30 0.08 POST-CON:6* 1 0.25 1 0.001 0.251 0.00 1 0.20 1 0.35 * Qio ** Q25 BREC, P.A. Dollar General - Store #24556 n. 2.4 Pipe Design Rational discharges from the delineated drainage areas were used to size pipes by solving Manning's equation iteratively for the normal depth. Table 7 - Pipe Design Summary See Appendix for complete pipe design table. 2.4.1 Outlet Design Outlet design for pipes discharging to ground surface was taken from Chapter 10 of HEC-14. Riprap D50 was calculated as: 4 l D50 = 0.2D(Qdesign gD2.5 3 ( D Where, D50 = Riprap median diameter (f t) Qdesign = Design discharge (f t3/s) D = Pipe diameter (f t) TW = Tailwater depth (ft) g = gravitational acceleration (32.2 f t/s2) Substituting the corresponding pipe diameters and design discharges into the equation above yields: Table 8 - Riprap Outlet Stone Sizing A minimum D50 of 5 inches was chosen for each pipe which corresponds to NCDOT Class A stone. Given the design D50, the dimensions of the apron were taken from Table 10.1 equations from HEC 141 . http://www.fhwa.dot.gov/engineering/hydraulics/pubs/06086/hecl 4ch l O.cfm BREC, P.A. Dollar General — Store #24556 7 t )s D50calc (in) NAME DIA (in) ftS/ Qmax \ s ftS Qdesign \ s ) PIPE-1 15 7.5 2.1 PIPE-2 15 12.5 5.6 PIPE-3 12 2.8 1.7 NAME DIA (in) 3 Qdesign f La = Apron length (f t) = 4D Da = Apron depth (f t) = 3.5D50 W1 = Upper width (f t) = 3D WZ = Lower width (f t) = 3D + (2/3) La Table 9 - Riprap Aron Dimensions NAME DIA (in) La (f t) Da (f t) W1 (ft) WZ (ft) PIPE-1 15 5 1.5 4 7 PIPE-2 15 5 1.5 4 7 PIPE-3 12 4 1.5 3 6 The modified curve numbers were used to route the first flush using an SCS 6 hour balanced storm distribution. The remaining design storms were routed with standard curve numbers and an SCS type II 24 hour storm distribution. Table 10 - Modified SCS Curve Numbers Name R CN POST-CON:1 0.95 99.57 POST-CON:2 0.92 99.30 POST-CON:3 0.93 99.39 POST-CON:4 0.95 99.57 POST-CON:5 0.17 84.66 POST-CON:6 0.05 77.22 The stage storage relationship for the infiltration basin is calculated using average end area values for the storage above the stone media. A porosity of 0.25 and 0.32 was used for sand and #57 clean stone, respectively to account for volume within those media layers. Table 11 — Infiltration Basin Stage Storage Table Stage V t) Elevation t) Area f t2 Porosity Total Vol ft3 ! 0 813 1,057+ - 0 0.5 813.5 1,057+ 0.25 132 1 814 1,057+ 0.32 301 2 815 1,057+ 0.32 639 3- 816- 1,057+ 0.32 1,228 3+ 816+ 2,083 1 1,228 3.75 816.75 2,600 1 2,984A 4 817 2,906 1 3,672 5 818 4,331 1 7,291 6 819 6,182 1 12,547 + Aprovided n Uprovided 2.6.2 Anti -floatation Calculations The outlet structure is a 3 ft x 3 ft x 3.5 ft precast concrete box with 6 in side and bottom wall thicknesses. Including concrete and reinforcing steel, the structure has an empty mass of Moutletempty = 3,751 lb. Assuming the total height of the box is exposed to buoyant forces, the volume of water displaced by the box is calculated from the outside dimensions. Vboxwater = 4.0 f t x 4.0 f t x 4.0 f t= 64 f t3 The buoyant force on the box is defined from the hydraulic forces acting lb Fb = VboxwaterPW = 64 f t3 x 62.4 ft3 = 3,994 lb Additional mass was added to the outlet structure by pouring a 6 in concrete slab over the bottom. BREC, P.A. Dollar General - Store #24556 10 MoutlettotQl = 3,751 lb + (3 f t)(3 f t)(0.5 f t) C150 l b3) = 4,426 lb > Fb 3.0 Results The design storm (1") is routed through the stormwater control measure and reaches a max storage depth of 0.5 ft above stone surface (3.5 ft above in -situ soil). The water quality volume is discharged over a period of 20 hours. — Storage: System (POST-CON-ROLMNGBALANCID 2022-09-1214:20:46) 2240 2016 1792 1568 1344 c 1120 `o 896 672 448 224 0 5 10 15 20 25 30 35 40 45 Time (hrs) Figure 1 - System Storage of Design Storm BREC, P.A. Dollar General — Store #24556 11 Appendix Table 12 - Pipe Design Table NAME DIA (IN) INV UP INV DOWN LEN (FT) S (FT/FT) n Q MAX (CFS) Q DESIGN (CFS) PIPE-1 15 818.25 817.25 87.5 0.011 0.012 7.5 2.1 PIPE-2 15 815.25 814.50 23.4 0.032 0.012 12.5 5.6 PIPE-3 12 817.00 816.10 168.0 0.005 0.012 2.8 1.7 Post -construction Design Storm BREC, P.A. Dollar General — Store #24556 13 BREC,PA Project Description File Name................................................................. POST-CON-ROUTING-BALANCED.SPF Description............................................................... C:\Users\justi\App Data\Local\Temp\3161032022_C100_ STORMWATER2_recover_1_27644_e86f114b.sv$ Project Options FlowUnits................................................................ CFS Elevation Type.......................................................... Elevation Hydrology Method ................................................... SCS TR-55 Time of Concentration (TOC) Method ..................... User -Defined Link Routing Method ............................................... Hydrodynamic Enable Overflow Ponding at Nodes ......................... YES Skip Steady State Analysis Time Periods ................. NO Analysis Options Start Analysis On ...................................................... 00:00:00 0:00:00 End Analysis On ........................................................ 00:00:00 0:00:00 Start Reporting On ................................................... 00:00:00 0:00:00 Antecedent Dry Days ............................................... 0 days Runoff (Dry Weather) Time Step ............................. 0 01:00:00 days hh:mm:ss Runoff (Wet Weather) Time Step ............................ 0 00:05:00 days hh:mm:ss Reporting Time Step ................................................ 0 00:00:05 days hh:mm:ss Routing Time Step .................................................... 5 seconds Number of Elements aty RainGages............................................................... 1 Sub ba si ns.................................................................. 6 Nodes........................................................................ 5 Junctions........................................................... 2 Outfalls............................................................. 2 Flow Diversions ................................................ 0 Inlets................................................................. 0 Storage Nodes .................................................. 1 Links.......................................................................... 5 Channels........................................................... 0 Pipes................................................................. 2 Pumps............................................................... 0 Orifices............................................................. 1 Weirs................................................................ 1 Outlets.............................................................. 1 Pollutants................................................................. 0 LandUses................................................................. 0 Rainfall Details SN Rain Gage Data Data Source Rainfall Rain State County Return Rainfall Rainfall ID Source ID Type Units Period Depth Distribution 1 SALISBURY Time Series 11 N-6H R- BALANCED Cumulative inches 0.00 BREC, PA Subbasin Summary SN Subbasin Area Peak Rate Weighted Total Total Total Peak Time of ID Factor Curve Rainfall Runoff Runoff Runoff Concentration Number Volume (ac) (in) (in) (ac-in) (cfs) (days hh:mm:ss) 1 {Site 1}.POST - CONA 0.16 484.00 99.57 1.00 0.95 0.15 0.33 0 00:05:00 2 {Site 1}.POST-CON:1 0.25 484.00 99.57 1.00 0.95 0.24 0.52 0 00:05:00 3 {Site 1}.POST-CON:2 0.23 484.00 99.30 1.00 0.92 0.21 0.47 0 00:05:00 4 {Site 1}.POST-CON:3 0.15 484.00 99.39 1.00 0.93 0.14 0.30 0 00:05:00 5 {Site 1}.POST-CON:5 0.04 484.00 84.66 1.00 0.13 0.01 0.01 0 00:05:00 6 {Site 1}.POST-CON:6 0.25 484.00 77.22 1.00 0.05 0.01 0.01 0 00:05:00 BREC, PA Node Summary SN Element ID Element Invert Ground/Rim Initial Surcharge Ponded Peak Max HGL Max Min Time of Total Type Elevation (Max) Water Elevation Area Inflow Elevation Surcharge Freeboard Peak Flooded Elevation Elevation Attained Depth Attained Flooding Volume Attained Occurrence (ft) (ft) (ft) (ft) (ft') (cfs) (ft) (ft) (ft) (days hh:mm) (ac-in) 1 SCM-RISER Junction 815.25 819.00 815.25 0.00 0.00 0.00 815.25 2 SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) Junction 815.00 819.00 815.00 0.00 0.00 0.00 815.00 3 OUTFALL-ABOVE-GROUND Outfall 814.75 0.00 814.75 4 OUTFALL-BELOW-GROUND Outfall 810.00 0.05 810.00 5 INFILTRATION Storage Node 813.00 819.00 813.00 0.00 1.64 816.50 0.00 3.75 0 00:00 0.00 0.00 6.00 0 00:00 0.00 0.00 BREC,PA Total Time Flooded (min) 0.00 0.00 0.00 BREC, PA Link Summary SN Element Element From To (Outlet) Length Inlet Outlet Average Diameter or Manning's Peak Design Flow Peak Flow/ Peak Flow ID Type (Inlet) Node Invert Invert Slope Height Roughness Flow Capacity Design Flow Velocity Node Elevation Elevation Ratio (ft) (ft) (ft) N (in) (cfs) (cfs) (ft/sec) 1 SCM-BARREL Pipe SCM-RISER SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) 10.00 815.25 815.00 2.5000 15.000 0.0120 0.00 11.06 0.00 0.00 2 SITE-ABOVE-GROUND-LINK(VIRTUAL) Pipe SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) OUTFALL-ABOVE-GROUND 10.00 815.00 814.75 2.5000 18.000 0.0120 0.00 17.99 0.00 0.00 3 SCM-SECONDARY Orifice INFILTRATION SCM-RISER 813.00 815.25 36.000 0.00 41N-SITU-SOIL Outlet INFILTRATION OUTFALL-BELOW-GROUND 813.00 810.00 0.05 5 EM-SPILLWAY Weir INFILTRATION SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) 813.00 815.00 0.00 BREC,PA Peak Flow Peak Flow Total Time Reported Depth Depth/ Surcharged Condition Total Depth Ratio (ft) (min) 0.00 0.00 0.00 Calculated 0.00 0.00 0.00 Calculated BREC, PA Subbasin Hydrology Subbasin : {Site 1}.POST - CONA Input Data Area(ac)............................................................ 0.16 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 99.57 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number - 0.16 - 99.57 Composite Area & Weighted CN 0.16 99.57 Subbasin Runoff Results Total Rainfall (in) .............................................. 1 Total Runoff(in)................................................ 0.95 Peak Runoff (cfs)............................................... 0.33 Weighted Curve Number .................................. 99.57 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA T T, 0 c c Subbasin : (Site 11.130ST- CON:4 1.7 1.6 ).9 ).8 ).7 ).6 ).5 ).4 ).3 ).2 ).1 Rainfall Intensity Graph 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 lit 0.12 0.1 0.08 0.06 0.04 0.02 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:1 Input Data Area(ac)............................................................ 0.25 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 99.57 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number - 0.25 - 99.57 Composite Area & Weighted CN 0.25 99.57 Subbasin Runoff Results Total Rainfall (in) .............................................. 1 Total Runoff(in)................................................ 0.95 Peak Runoff (cfs)............................................... 0.52 Weighted Curve Number .................................. 99.57 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 1}.POST-CON:1 0. 0. c 0. 0. 0. 0. 0. 0. 0. 0. � t 0. `0 0. c 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. Rainfall Intensity Graph 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph 52 .5 l8 l6 14 l2 .4 38 )6 34 32 3 >g t6 >4 ?2 .2 18 16 14 12 1 )8 )6 )4 )2 U L 4 b 6 lU lL 14 lb ltl LU GL L4 Lb Zb SU SL 34 Sb Jtl 4U 4L 44 4b Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:2 Input Data Area(ac)............................................................ 0.23 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 99.3 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number - 0.23 - 99.3 Composite Area & Weighted CN 0.23 99.3 Subbasin Runoff Results Total Rainfall (in) .............................................. 1 Total Runoff(in)................................................ 0.92 Peak Runoff (cfs)............................................... 0.47 Weighted Curve Number .................................. 99.3 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 1}.POST-CON:2 c 0. 0. 0. 0. c 0.. 0.. 0.. 0.. c in 0. 0. `0 0. 0. c 0. 0. 0. 0. c 0.i 0.i 0.i 0.i Rainfall Intensity Graph 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph 18 �s 14 2 4 18 16 w Iz 3 '8 !6 A 2--t 2 8 6 4 2 1 18 16 14 12 U L 4 b d lU lL l4 lb ltl LU GL L4 Lb Zb SU SL 34 Sb Jtl 4U 4L 44 4b Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:3 Input Data Area(ac)............................................................ 0.15 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 99.39 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number - 0.15 - 99.39 Composite Area & Weighted CN 0.15 99.39 Subbasin Runoff Results Total Rainfall (in) .............................................. 1 Total Runoff(in)................................................ 0.93 Peak Runoff (cfs)............................................... 0.3 Weighted Curve Number .................................. 99.39 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA T T, 0 c c Subbasin : (Site 1}.POST-CON:3 Rainfall Intensity Graph 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:5 Input Data Area(ac)............................................................ 0.04 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 84.66 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number - 0.04 - 84.66 Composite Area & Weighted CN 0.04 84.66 Subbasin Runoff Results Total Rainfall (in) .............................................. 1 Total Runoff(in)................................................ 0.13 Peak Runoff (cfs)............................................... 0.01 Weighted Curve Number .................................. 84.66 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 1}.POST-CON:5 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0. 0. �.0 &0.0 w0.0 C0.0 Qf0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rainfall Intensity Graph 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph 5 01 01 09 09 08 08 07 07 O6 O6 05 04 04 04 03 03 02 02 01 4 4 3 3 2 2 1 1 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:6 Input Data Area(ac)............................................................ 0.25 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 77.22 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number - 0.25 - 77.22 Composite Area & Weighted CN 0.25 77.22 Subbasin Runoff Results Total Rainfall (in) .............................................. 1 Total Runoff(in)................................................ 0.05 Peak Runoff (cfs)............................................... 0.01 Weighted Curve Number .................................. 77.22 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 1}.POST-CON:6 0.01 0.01 0.01 0. 0. 0.0 0.0 0.0 0.0 NO.o °o.o Co.o Qfo.o 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Rainfall Intensity Graph 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph 1 1 01 01 os os 08 08 07 07 06 06 05 04 04 04 03 03 02 02 01 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 Time (hrs) 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 Time (hrs) BREC, PA Junction Input SN Element Invert Ground/Rim Ground/Rim Initial Initial Surcharge Surcharge Ponded Minimum ID Elevation (Max) (Max) Water Water Elevation Depth Area Pipe Elevation Offset Elevation Depth Cover (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft') (in) 1 SCM-RISER 815.25 819.00 3.75 815.25 0.00 0.00-819.00 0.00 0.00 2 SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) 815.00 819.00 4.00 815.00 0.00 0.00-819.00 0.00 0.00 BREC, PA Junction Results SN Element Peak Peak Max HGL Max HGL Max Min Average HGL Average HGL Time of Time of Total Total Time ID Inflow Lateral Elevation Depth Surcharge Freeboard Elevation Depth Max HGL Peak Flooded Flooded Inflow Attained Attained Depth Attained Attained Attained Occurrence Flooding Volume Attained Occurrence (cfs) (cfs) (ft) (ft) (ft) (ft) (ft) (ft) (days hh:mm) (days hh:mm) (ac-in) (min) 1 SCM-RISER 0.00 0.00 815.25 0.00 0.00 3.75 815.25 0.00 0 00:00 0 00:00 0.00 0.00 2 SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) 0.00 0.00 815.00 0.00 0.00 6.00 815.00 0.00 0 00:00 0 00:00 0.00 0.00 BREC, PA Pipe Input SN Element ID Length Inlet Inlet Outlet Outlet Total Average Pipe Pipe Pipe Manning's Entrance Exit/Bend Additional Initial Invert Invert Invert Invert Drop Slope Shape Diameter or Width Roughness Losses Losses Losses Flow Elevation Offset Elevation Offset Height (ft) (ft) (ft) (ft) (ft) (ft) N (in) (in) (cfs) 1 SCM-BARREL 10.00 815.25 0.00 815.00 0.00 0.25 2.5000 CIRCULAR 15.000 15.000 0.0120 0.5000 0.5000 0.0000 0.00 2 SITE-ABOVE-GROUND-LINK(VIRTUAL) 10.00 815.00 0.00 814.75 0.00 0.25 2.5000 CIRCULAR 18.000 18.000 0.0120 0.5000 0.5000 0.0000 0.00 BREC,PA Flap No. of Gate Barrels No No BREC, PA Pipe Results SN Element ID Peak Time of Design Flow Peak Flow/ Peak Flow Travel Peak Flow Peak Flow Total Time Froude Reported Flow Peak Flow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition Occurrence Ratio Total Depth Ratio (cfs) (days hh:mm) (cfs) (ft/sec) (min) (ft) (min) 1 SCM-BARREL 0.00 0 00:00 11.06 0.00 0.00 0.00 0.00 0.00 Calculated 2 SITE-ABOVE-GROUND-LINK(VIRTUAL) 0.00 0 00:00 17.99 0.00 0.00 0.00 0.00 0.00 Calculated BREC, PA Storage Nodes Storage Node : INFILTRATION Input Data Invert Elevation (ft)............................................................................... 813.00 Max (Rim) Elevation (ft)........................................................................ 819.00 Max (Rim) Offset (ft)............................................................................. 6.00 Initial Water Elevation (ft)..................................................................... 813.00 Initial Water Depth (ft).......................................................................... 0.00 Ponded Area (ft2)................................................................................... 0.00 Evaporation Loss................................................................................... 0.00 Storage Area Volume Curves Storage Curve : INFILTRATION Stage Storage Storage Area Volume (ft) (ft2) (ft') 0 240 0 0.5 240 120 0.51 310 122.75 3 310 894.65 3.01 2083 906.62 4 2906 3376.18 5 4331 6994.68 6 6182 12251.18 BREC,PA Storage Area Volume Curves Storage Volume (ft3) 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 6,000 Storage Area (ft') Storage Area — Storage Volume BREC, PA Storage Node : INFILTRATION (continued) Outflow Weirs Outflow Orifices SN Element Weir Flap Crest Crest Length Weir Total Discharge ID Type Gate Elevation Offset Height Coefficient (ft) (ft) (ft) (ft) 1 EM-SPILLWAY Trapezoidal No 817.75 4.75 10.00 1.25 3.33 SN Element Orifice Orifice Flap Circular Rectangular Rectangular Orifice Orifice ID Type Shape Gate Orifice Orifice Orifice Invert Coefficient Diameter Height Width Elevation (in) (in) (in) (ft) 1 SCM-SECONDARY Bottom Rectangular No 36.00 36.00 817.00 0.63 Output Summary Results Peak Inflow (cfs).................................................................................... 1.64 Peak Lateral Inflow (cfs)........................................................................ 1.64 Peak Outflow (cfs)................................................................................. 0.05 Peak Exfiltration Flow Rate (cfm).......................................................... 0 Max HGL Elevation Attained (ft)............................................................ 816.5 Max HGL Depth Attained (ft)................................................................. 3.5 Average HGL Elevation Attained (ft)..................................................... 813.9 Average HGL Depth Attained (ft).......................................................... 0.9 Time of Max HGL Occurrence (days hh:mm)........................................ 0 04:57 Total Exfiltration Volume (1000-ft3)...................................................... 0 Total Flooded Volume (ac-in)................................................................ 0 Total Time Flooded (min)...................................................................... 0 Total Retention Time (sec).................................................................... 0 Post -construction 10 Year, 24 Hour BREC, P.A. Dollar General — Store #24556 14 BREC,PA Project Description File Name ..................................................... POST-CON-ROUTING.SPF Description .................................................. C:\Users\justi\App Data\Local\Temp\3161032022_C100_STORMWA TER2_recover_1_27644_e86f114b.sv$ Project Options Flow Units .................................................... CFS Elevation Type ............................................. Elevation Hydrology Method ...................................... SCS TR-55 Time of Concentration (TOC) Method ........ User -Defined Link Routing Method ................................... Hydrodynamic Enable Overflow Ponding at Nodes ............ YES Skip Steady State Analysis Time Periods ..... NO Analysis Options Start Analysis On .......................................... 00:00:00 0:00:00 End Analysis On ........................................... 00:00:00 0:00:00 Start Reporting On ....................................... 00:00:00 0:00:00 Antecedent Dry Days ................................... 0 days Runoff (Dry Weather) Time Step ................. 0 01:00:00 days hh:mm:ss Runoff (Wet Weather) Time Step ............... 0 00:05:00 days hh:mm:ss Reporting Time Step .................................... 0 00:00:05 days hh:mm:ss Routing Time Step ....................................... 5 seconds Number of Elements my RainGages ................................................... 1 Sub ba si ns...................................................... 6 Nodes............................................................ 5 Junctions .............................................. 2 Outfalls................................................ 2 Flow Diversions .................................... 0 Inlets.................................................... 0 Storage Nodes ..................................... 1 Links.............................................................. 5 Channels.............................................. 0 Pipes..................................................... 2 Pumps.................................................. 0 Orifices................................................. 1 Weirs.................................................... 1 Outlets................................................. 1 Pollutants..................................................... 0 LandUses ..................................................... 0 Rainfall Details SN Rain Gage Data Data Source Rainfall Rain ID Source ID Type Units 1 SALISBURY Time Series 10YR-24HR Cumulative inches State County Return Rainfall Rainfall Period Depth Distribution (years) (inches) North Carolina Rowan 10.00 4.80 SCS Type II 24-hr BREC, PA Subbasin Summary SN Subbasin Area Peak Rate Weighted Total Total Total Peak Time of ID Factor Curve Rainfall Runoff Runoff Runoff Concentration Number Volume (ac) (in) (in) (ac-in) (cfs) (days hh:mm:ss) 1 {Site 1}.POST - CONA 0.16 484.00 98.00 4.80 4.56 0.73 1.01 0 00:05:00 2 {Site 1}.POST-CON:1 0.25 484.00 98.00 4.80 4.56 1.14 1.57 0 00:05:00 3 {Site 1}.POST-CON:2 0.23 484.00 96.80 4.80 4.42 1.02 1.44 0 00:05:00 4 {Site 1}.POST-CON:3 0.15 484.00 97.20 4.80 4.47 0.67 0.92 0 00:05:00 5 {Site 1}.POST-CON:5 0.04 484.00 65.80 4.80 1.57 0.06 0.09 0 00:05:00 6 {Site 1}.POST-CON:6 0.25 484.00 61.00 4.80 1.25 0.31 0.46 0 00:05:00 BREC, PA Node Summary SN Element ID Element Invert Ground/Rim Initial Surcharge Ponded Peak Max HGL Max Min Time of Total Type Elevation (Max) Water Elevation Area Inflow Elevation Surcharge Freeboard Peak Flooded Elevation Elevation Attained Depth Attained Flooding Volume Attained Occurrence (ft) (ft) (ft) (ft) (ft') (cfs) (ft) (ft) (ft) (days hh:mm) (ac-in) 1 SCM-RISER Junction 815.25 819.00 815.25 0.00 0.00 5.08 816.32 2 SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) Junction 815.00 819.00 815.00 0.00 0.00 5.08 815.87 3 OUTFALL-ABOVE-GROUND Outfall 814.75 5.08 815.30 4 OUTFALL-BELOW-GROUND Outfall 810.00 0.05 810.00 5 INFILTRATION Storage Node 813.00 819.00 813.00 0.00 5.47 817.25 0.00 2.68 0 00:00 0.00 0.00 4.88 0 00:00 0.00 0.00 BREC,PA Total Time Flooded (min) 0.00 0.00 0.00 BREC, PA Link Summary SN Element Element From To (Outlet) Length Inlet Outlet Average Diameter or Manning's Peak Design Flow Peak Flow/ Peak Flow ID Type (Inlet) Node Invert Invert Slope Height Roughness Flow Capacity Design Flow Velocity Node Elevation Elevation Ratio (ft) (ft) (ft) N (in) (cfs) (cfs) (ft/sec) 1 SCM-BARREL Pipe SCM-RISER SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) 10.00 815.25 815.00 2.5000 15.000 0.0120 5.08 11.06 0.46 4.98 2 SITE-ABOVE-GROUND-LINK(VIRTUAL) Pipe SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) OUTFALL-ABOVE-GROUND 10.00 815.00 814.75 2.5000 18.000 0.0120 5.08 17.99 0.28 6.22 3 SCM-SECONDARY Orifice INFILTRATION SCM-RISER 813.00 815.25 36.000 5.08 41N-SITU-SOIL Outlet INFILTRATION OUTFALL-BELOW-GROUND 813.00 810.00 0.05 5 EM-SPILLWAY Weir INFILTRATION SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) 813.00 815.00 0.00 BREC,PA Peak Flow Peak Flow Total Time Reported Depth Depth/ Surcharged Condition Total Depth Ratio (ft) (min) 0.97 0.77 0.00 Calculated 0.71 0.47 0.00 Calculated BREC, PA Subbasin Hydrology Subbasin : {Site 1}.POST - CONA Input Data Area(ac)............................................................ 0.16 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 98 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number 0.16 - 98 Composite Area & Weighted CN 0.16 98 Subbasin Runoff Results Total Rainfall (in) .............................................. 4.8 Total Runoff(in)................................................ 4.56 Peak Runoff (cfs)............................................... 1.01 Weighted Curve Number .................................. 98 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 11.130ST- CON:4 DA 0 DA 0 0.i 0 _ 0.( N 0 U w DA O 0 0., 0 0.: 0 0.; 0 0.' 0 0.( Rainfall Intensity Graph i i i V i i U 2 4 b tl lU 12 14 lb ltf LU 22 24 2b 28 JU 32 J4 Jb 38 4U 42 44 4b 48 Time (hrs) Runoff Hydrograph 5 1 5 5 B 5 lid I 1 11 1 11 7 5 6 5 5 5 4 5 3 5 2 5 1 5- L ±1 - -L�i I I I U L 4 b 6 lU lL 14 lb ltl LU GL L4 Lb Zb JU JL J4 Jb Jd 4U 4L 44 4b Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:1 Input Data Area(ac)............................................................ 0.25 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 98 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number 0.25 - 98 Composite Area & Weighted CN 0.25 98 Subbasin Runoff Results Total Rainfall (in) .............................................. 4.8 Total Runoff(in)................................................ 4.56 Peak Runoff (cfs)............................................... 1.57 Weighted Curve Number .................................. 98 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 1}.POST-CON:1 Rainfall Intensity Graph 7. 6. 5. I 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph 0.9- 0.8- 0.7- 0.6- 0.5- 0.4- 0.3- 0.2- 0.1- 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:2 Input Data Area(ac)............................................................ 0.23 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 96.8 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number - 0.23 - 96.8 Composite Area & Weighted CN 0.23 96.8 Subbasin Runoff Results Total Rainfall (in) .............................................. 4.8 Total Runoff(in)................................................ 4.42 Peak Runoff (cfs)............................................... 1.44 Weighted Curve Number .................................. 96.8 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA T T, 0 c c Subbasin : (Site 1}.POST-CON:2 7. 6. 5. Rainfall Intensity Graph I 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph 1.55 1.5 1.45 1.4 1.35 1.3 1.25 1.2 1.15 1.1 1.05 1 0.95 0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:3 Input Data Area(ac)............................................................ 0.15 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 97.2 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number - 0.15 - 97.2 Composite Area & Weighted CN 0.15 97.2 Subbasin Runoff Results Total Rainfall (in) .............................................. 4.8 Total Runoff(in)................................................ 4.47 Peak Runoff (cfs)............................................... 0.92 Weighted Curve Number .................................. 97.2 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 1}.POST-CON:3 7. 6. 5. 0.9 0. 0.8 0. 0.7 0. 0.6 0. `cNi 0.5 w 0. `0 0.4 0. 0.3 0. 0.2 0. 0.1 0. 0.0 Rainfall Intensity Graph 7 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph i i i V i I I II U L 4 b b "IU lL 14 lb 1b LU GL L4 Lb Zb SU SL 34 Sb M 4U 4L 44 4b Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:5 Input Data Area(ac)............................................................ 0.04 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 65.8 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number - 0.04 - 65.8 Composite Area & Weighted CN 0.04 65.8 Subbasin Runoff Results Total Rainfall (in) .............................................. 4.8 Total Runoff(in)................................................ 1.57 Peak Runoff (cfs)............................................... 0.09 Weighted Curve Number .................................. 65.8 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 1}.POST-CON:5 7. 6. 5. 0. 0.09 0.0 0.08 0.0 0.07 0.0 0.06 0.0 40.05 0 0.0 c �0.04 0.0 0.03 0.0 0.02 0.0 0.01 0.0 0.00 Rainfall Intensity Graph 7 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph U L 4 b 6 lU lL 14 lb ltl LU GL L4 Lb Zb JU JL J4 Jb Jb 4U 4L 44 4b Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:6 Input Data Area(ac)............................................................ 0.25 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 61 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number 0.25 - 61 Composite Area & Weighted CN 0.25 61 Subbasin Runoff Results Total Rainfall (in) .............................................. 4.8 Total Runoff(in)................................................ 1.25 Peak Runoff (cfs)............................................... 0.46 Weighted Curve Number .................................. 61 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 1}.POST-CON:6 7. 6. 5. 0. 0. 0. 0. c 0. 0. 0. 0. c 0. � 0. w 0. 0 0. 0. 0. 0. 0. 0. 0. 0. 0. Rainfall Intensity Graph 7 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph is W )2 .4 38 is 32 .3 -8 t6 >q >_2 .2 18 I6 14 12 1 )8 76 )4 )2 U L 4 b 15 lU lL l4 lb ltl LU GL L4 Lb Lis JU JL J4 Jb Jd 4U 4L 44 4b Time (hrs) BREC, PA Junction Input SN Element Invert Ground/Rim Ground/Rim Initial Initial Surcharge Surcharge Ponded Minimum ID Elevation (Max) (Max) Water Water Elevation Depth Area Pipe Elevation Offset Elevation Depth Cover (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft') (in) 1 SCM-RISER 815.25 819.00 3.75 815.25 0.00 0.00-819.00 0.00 0.00 2 SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) 815.00 819.00 4.00 815.00 0.00 0.00-819.00 0.00 0.00 BREC, PA Junction Results SN Element Peak Peak Max HGL Max HGL Max Min Average HGL Average HGL Time of Time of Total Total Time ID Inflow Lateral Elevation Depth Surcharge Freeboard Elevation Depth Max HGL Peak Flooded Flooded Inflow Attained Attained Depth Attained Attained Attained Occurrence Flooding Volume Attained Occurrence (cfs) (cfs) (ft) (ft) (ft) (ft) (ft) (ft) (days hh:mm) (days hh:mm) (ac-in) (min) 1 SCM-RISER 5.08 0.00 816.32 1.07 0.00 2.68 815.27 0.02 0 11:56 0 00:00 0.00 0.00 2 SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) 5.08 0.00 815.87 0.87 0.00 4.88 815.02 0.02 0 11:57 0 00:00 0.00 0.00 BREC, PA Pipe Input SN Element ID Length Inlet Inlet Outlet Outlet Total Average Pipe Pipe Pipe Manning's Entrance Exit/Bend Additional Initial Invert Invert Invert Invert Drop Slope Shape Diameter or Width Roughness Losses Losses Losses Flow Elevation Offset Elevation Offset Height (ft) (ft) (ft) (ft) (ft) (ft) N (in) (in) (cfs) 1 SCM-BARREL 10.00 815.25 0.00 815.00 0.00 0.25 2.5000 CIRCULAR 15.000 15.000 0.0120 0.5000 0.5000 0.0000 0.00 2 SITE-ABOVE-GROUND-LINK(VIRTUAL) 10.00 815.00 0.00 814.75 0.00 0.25 2.5000 CIRCULAR 18.000 18.000 0.0120 0.5000 0.5000 0.0000 0.00 BREC,PA Flap No. of Gate Barrels No No BREC, PA Pipe Results SN Element Peak Time of Design Flow Peak Flow/ Peak Flow Travel Peak Flow Peak Flow Total Time Froude Reported ID Flow Peak Flow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition Occurrence Ratio Total Depth Ratio (cfs) (days hh:mm) (cfs) (ft/sec) (min) (ft) (min) 1 SCM-BARREL 5.08 0 11:57 11.06 0.46 4.98 0.03 0.97 0.77 0.00 Calculated 2 SITE-ABOVE-GROUND-LINK(VIRTUAL) 5.08 0 11:57 17.99 0.28 6.22 0.03 0.71 0.47 0.00 Calculated BREC, PA Storage Nodes Storage Node : INFILTRATION Input Data Invert Elevation (ft)............................................................................... 813.00 Max (Rim) Elevation (ft)........................................................................ 819.00 Max (Rim) Offset (ft)............................................................................. 6.00 Initial Water Elevation (ft)..................................................................... 813.00 Initial Water Depth (ft).......................................................................... 0.00 Ponded Area (ft2)................................................................................... 0.00 Evaporation Loss................................................................................... 0.00 Storage Area Volume Curves Storage Curve : INFILTRATION Stage Storage Storage Area Volume (ft) (ft2) (ft') 0 240 0 0.5 240 120 0.51 310 122.75 3 310 894.65 3.01 2083 906.62 4 2906 3376.18 5 4331 6994.68 6 6182 12251.18 BREC,PA Storage Area Volume Curves Storage Volume (ft3) 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 6,000 Storage Area (ft') Storage Area — Storage Volume BREC, PA Storage Node : INFILTRATION (continued) Outflow Weirs Outflow Orifices SN Element Weir Flap Crest Crest Length Weir Total Discharge ID Type Gate Elevation Offset Height Coefficient (ft) (ft) (ft) (ft) 1 EM-SPILLWAY Trapezoidal No 817.50 4.50 10.00 1.25 3.33 SN Element Orifice Orifice Flap Circular Rectangular Rectangular Orifice Orifice ID Type Shape Gate Orifice Orifice Orifice Invert Coefficient Diameter Height Width Elevation (in) (in) (in) (ft) 1 SCM-SECONDARY Bottom Rectangular No 36.00 36.00 817.00 0.63 Output Summary Results Peak Inflow (cfs).................................................................................... 5.47 Peak Lateral Inflow (cfs)........................................................................ 5.47 Peak Outflow (cfs)................................................................................. 5.13 Peak Exfiltration Flow Rate (cfm).......................................................... 0 Max HGL Elevation Attained (ft)............................................................ 817.25 Max HGL Depth Attained (ft)................................................................. 4.25 Average HGL Elevation Attained (ft)..................................................... 815.56 Average HGL Depth Attained (ft).......................................................... 2.56 Time of Max HGL Occurrence (days hh:mm)........................................ 0 11:56 Total Exfiltration Volume (1000-ft3)...................................................... 0 Total Flooded Volume (ac-in)................................................................ 0 Total Time Flooded (min)...................................................................... 0 Total Retention Time (sec).................................................................... 0 Post -construction 100 Year, 24 Hour BREC, P.A. Dollar General — Store #24556 15 BREC,PA Project Description File Name ..................................................... POST-CON-ROUTING.SPF Description................................................... C:\Users\justi\App Data\Local\Temp\3161032022_C100_STORMWA TER2_recover_1_27644_e86f114b.sv$ Project Options Flow Units .................................................... CFS Elevation Type ............................................. Elevation Hydrology Method ....................................... SCS TR-55 Time of Concentration (TOC) Method ......... User -Defined Link Routing Method ................................... Hydrodynamic Enable Overflow Ponding at Nodes ............. YES Skip Steady State Analysis Time Periods ..... NO Analysis Options Start Analysis On .......................................... 00:00:00 0:00:00 End Analysis On ........................................... 00:00:00 0:00:00 Start Reporting On ....................................... 00:00:00 0:00:00 Antecedent Dry Days ................................... 0 days Runoff (Dry Weather) Time Step ................. 0 01:00:00 days hh:mm:ss Runoff (Wet Weather) Time Step ................ 0 00:05:00 days hh:mm:ss Reporting Time Step .................................... 0 00:00:05 days hh:mm:ss Routing Time Step ........................................ 5 seconds Number of Elements my RainGages ................................................... 1 Sub ba si ns...................................................... 6 Nodes............................................................ 5 Junctions .............................................. 2 Outfalls................................................. 2 Flow Diversions .................................... 0 Inlets..................................................... 0 Storage Nodes ...................................... 1 Links.............................................................. 5 Channels............................................... 0 Pipes..................................................... 2 Pumps................................................... 0 Orifices................................................. 1 Weirs.................................................... 1 Outlets.................................................. 1 Pollutants..................................................... 0 LandUses ..................................................... 0 Rainfall Details SN Rain Gage Data Data Source Rainfall Rain ID Source ID Type Units 1 SALISBURY Time Series 100YR-24HR Cumulative inches State County Return Rainfall Rainfall Period Depth Distribution (years) (inches) North Carolina Rowan 100.00 7.13 SCS Type II 24-hr BREC, PA Subbasin Summary SN Subbasin Area Peak Rate Weighted Total Total Total Peak Time of ID Factor Curve Rainfall Runoff Runoff Runoff Concentration Number Volume (ac) (in) (in) (ac-in) (cfs) (days hh:mm:ss) 1 {Site 1}.POST - CONA 0.16 484.00 98.00 7.13 6.89 1.10 1.50 0 00:05:00 2 {Site 1}.POST-CON:1 0.25 484.00 98.00 7.13 6.89 1.72 2.34 0 00:05:00 3 {Site 1}.POST-CON:2 0.23 484.00 96.80 7.13 6.75 1.55 2.15 0 00:05:00 4 {Site 1}.POST-CON:3 0.15 484.00 97.20 7.13 6.80 1.02 1.38 0 00:05:00 5 {Site 1}.POST-CON:5 0.04 484.00 65.80 7.13 3.27 0.13 0.20 0 00:05:00 6 {Site 1}.POST-CON:6 0.25 484.00 61.00 7.13 2.80 0.70 1.09 0 00:05:00 BREC, PA Node Summary SN Element ID Element Invert Ground/Rim Initial Surcharge Ponded Peak Max HGL Max Min Time of Total Type Elevation (Max) Water Elevation Area Inflow Elevation Surcharge Freeboard Peak Flooded Elevation Elevation Attained Depth Attained Flooding Volume Attained Occurrence (ft) (ft) (ft) (ft) (ft') (cfs) (ft) (ft) (ft) (days hh:mm) (ac-in) 1 SCM-RISER Junction 815.25 819.00 815.25 0.00 0.00 8.09 817.01 2 SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) Junction 815.00 819.00 815.00 0.00 0.00 8.09 816.18 3 OUTFALL-ABOVE-GROUND Outfall 814.75 8.09 815.46 4 OUTFALL-BELOW-GROUND Outfall 810.00 0.05 810.00 5 INFILTRATION Storage Node 813.00 819.00 813.00 0.00 8.65 817.35 0.00 1.99 0 00:00 0.00 0.00 4.57 0 00:00 0.00 0.00 BREC,PA Total Time Flooded (min) 0.00 0.00 0.00 BREC, PA Link Summary SN Element Element From To (Outlet) Length Inlet Outlet Average Diameter or Manning's Peak Design Flow Peak Flow/ Peak Flow ID Type (Inlet) Node Invert Invert Slope Height Roughness Flow Capacity Design Flow Velocity Node Elevation Elevation Ratio (ft) (ft) (ft) N (in) (cfs) (cfs) (ft/sec) 1 SCM-BARREL Pipe SCM-RISER SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) 10.00 815.25 815.00 2.5000 15.000 0.0120 8.09 11.06 0.73 6.65 2 SITE-ABOVE-GROUND-LINK(VIRTUAL) Pipe SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) OUTFALL-ABOVE-GROUND 10.00 815.00 814.75 2.5000 18.000 0.0120 8.09 17.99 0.45 6.95 3 SCM-SECONDARY Orifice INFILTRATION SCM-RISER 813.00 815.25 36.000 8.09 41N-SITU-SOIL Outlet INFILTRATION OUTFALL-BELOW-GROUND 813.00 810.00 0.05 5 EM-SPILLWAY Weir INFILTRATION SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) 813.00 815.00 0.00 BREC,PA Peak Flow Peak Flow Total Time Reported Depth Depth/ Surcharged Condition Total Depth Ratio (ft) (min) 1.21 0.97 0.00 Calculated 0.94 0.63 0.00 Calculated BREC, PA Subbasin Hydrology Subbasin : {Site 1}.POST - CONA Input Data Area(ac)............................................................ 0.16 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 98 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number 0.16 - 98 Composite Area & Weighted CN 0.16 98 Subbasin Runoff Results Total Rainfall (in) .............................................. 7.13 Total Runoff(in)................................................ 6.89 Peak Runoff (cfs)............................................... 1.5 Weighted Curve Number .................................. 98 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 11.130ST- CON:4 9. 8. 7. 6. 5. m `c 4 M 3. 2. 1. 0. T T, 0 c c Rainfall Intensity Graph I 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph 1.55 1.5 1.45 1.4 1.35 1.3 1.25 1.2 1.15 1.1 1.05 1 0.95 0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:1 Input Data Area(ac)............................................................ 0.25 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 98 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number 0.25 - 98 Composite Area & Weighted CN 0.25 98 Subbasin Runoff Results Total Rainfall (in) .............................................. 7.13 Total Runoff(in)................................................ 6.89 Peak Runoff (cfs)............................................... 2.34 Weighted Curve Number .................................. 98 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 1}.POST-CON:1 Rainfall Intensity Graph 10.5 10 9.5 9 8.5 8 7.5 7 6.5 6 5.5 5 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) 2.5 2. 2 2. 2.1 0 0 0 0 0 0 0 0 0 Runoff Hydrograph 4 3 2 2 9 B 7 6 5 4 3 2 1 1 9 B 7 6 5 4---d I 1 1 3 2 1 U L 4 b t$ lU lL 14 lb 16 LU GL L4 Lb Lis JU JL 14 Jb -ju 4U 4L 44 4b Time (hrs) U L 4 b t$ lU lL 14 lb 16 LU GL L4 Lb Lis JU JL 14 Jb -ju 4U 4L 44 4b Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:2 Input Data Area(ac)............................................................ 0.23 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 96.8 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number - 0.23 - 96.8 Composite Area & Weighted CN 0.23 96.8 Subbasin Runoff Results Total Rainfall (in) .............................................. 7.13 Total Runoff(in)................................................ 6.75 Peak Runoff (cfs)............................................... 2.15 Weighted Curve Number .................................. 96.8 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 1}.POST-CON:2 Rainfall Intensity Graph 10.5 10 9.5 9 8.5 8 7.5 7 6.5 6 5.5 5 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph 2.3 2. 1 1 1 1 1 1 N 1 1 `0 1 c c 0 0 0 0 0 0 0 0 0 2 2.1 1 1 1 1 1 1 N 1 1 `0 1 c c 0 0 0 0 0 0 0 0 0 2 9 B 7 6 5 4 3 2 1 1 9 B 7 6 5 4 3 2 1 U L 4 b i5 lU lL 14 lb 1b LU GL L4 Lb Zb JU JL 14 Jb Jtl 4U 4L 44 4b Time (hrs) U L 4 b i5 lU lL 14 lb 1b LU GL L4 Lb Zb JU JL 14 Jb Jtl 4U 4L 44 4b Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:3 Input Data Area(ac)............................................................ 0.15 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 97.2 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number - 0.15 - 97.2 Composite Area & Weighted CN 0.15 97.2 Subbasin Runoff Results Total Rainfall (in) .............................................. 7.13 Total Runoff(in)................................................ 6.8 Peak Runoff (cfs)............................................... 1.38 Weighted Curve Number .................................. 97.2 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 1}.POST-CON:3 Rainfall Intensity Graph 10.5 10 9.5 9 8.5 8 7.5 7 6.5 6 5.5 5 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) O.f 0 _ O.f 0 U O.i `0 0 c c O.f (if 0 0.: 0 0., 0 0." 0 0.. 0 0.' 0 0.f Runoff Hydrograph a 5 3 5-- 2-- 5-- 1-- 5-- 1. 5 -M 9 5 B 5 7 5 6 5 5 5 4 5 3 5 2 5 1 5 U L 4 b 6 lU lL 14 lb ltl LU GL L4 Lb zu JU JL J4 Jb Jtl 41.1 4L 44 4b Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:5 Input Data Area(ac)............................................................ 0.04 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 65.8 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number - 0.04 - 65.8 Composite Area & Weighted CN 0.04 65.8 Subbasin Runoff Results Total Rainfall (in) .............................................. 7.13 Total Runoff(in)................................................ 3.27 Peak Runoff (cfs)............................................... 0.2 Weighted Curve Number .................................. 65.8 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA Subbasin : (Site 1}.POST-CON:5 Rainfall Intensity Graph 10.5 10 9.5 9 8.5 8 7.5 7 6.5 6 5.5 5 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) 0. 0. c 0. 0. 0. 0. 0. 0. 0. w 0. U w 0. O 0. 0. 0. 0. 0. 0. 0. 0. 0. Runoff Hydrograph '1 2 9 8 7 s 5 4 3 2 1 1 9 18 17 16 5 14 3 12 11 ELL U L 4 b i5 lU lL 14 lb 1b LU GL L4 Lb Zb JU JL J4 Jb Jtl 4U 4L 44 4b Time (hrs) BREC, PA Subbasin : {Site 1}.POST-CON:6 Input Data Area(ac)............................................................ 0.25 Peak Rate Factor ............................................... 484 Weighted Curve Number .................................. 61 Rain Gage ID ..................................................... SALISBURY Composite Curve Number 32 Area Soil Curve Soil/Surface Description (acres) Group Number 0.25 - 61 Composite Area & Weighted CN 0.25 61 Subbasin Runoff Results Total Rainfall (in) .............................................. 7.13 Total Runoff(in)................................................ 2.8 Peak Runoff (cfs)............................................... 1.09 Weighted Curve Number .................................. 61 Time of Concentration (days hh:mm:ss) .......... 0 00:05:00 BREC, PA 0.9 0. 0.8 0. 0.7 0. 30.6 0, 0 0.5 (If 0. 0.4 0. 0.3 0. 0.2 0. 0.1 0. 0.0 Subbasin : (Site 1}.POST-CON:6 Rainfall Intensity Graph 10.5 10 9.5 9 8.5 8 7.5 7 6.5 6 5.5 5 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 Time (hrs) Runoff Hydrograph 1.15 1.1 1.05 t i V i U L 4 b i5 lU lL 14 lb 1b LU GL L4 Lb Zb JU JL 14 Jb Jtl 4U 4L 44 4b Time (hrs) BREC, PA Junction Input SN Element Invert Ground/Rim Ground/Rim Initial Initial Surcharge Surcharge Ponded Minimum ID Elevation (Max) (Max) Water Water Elevation Depth Area Pipe Elevation Offset Elevation Depth Cover (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft') (in) 1 SCM-RISER 815.25 819.00 3.75 815.25 0.00 0.00-819.00 0.00 0.00 2 SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) 815.00 819.00 4.00 815.00 0.00 0.00-819.00 0.00 0.00 BREC, PA Junction Results SN Element Peak Peak Max HGL Max HGL Max Min Average HGL Average HGL Time of Time of Total Total Time ID Inflow Lateral Elevation Depth Surcharge Freeboard Elevation Depth Max HGL Peak Flooded Flooded Inflow Attained Attained Depth Attained Attained Attained Occurrence Flooding Volume Attained Occurrence (cfs) (cfs) (ft) (ft) (ft) (ft) (ft) (ft) (days hh:mm) (days hh:mm) (ac-in) (min) 1 SCM-RISER 8.09 0.00 817.01 1.76 0.00 1.99 815.29 0.04 0 11:56 0 00:00 0.00 0.00 2 SITE-ABOVE-GROUND-JUNCTION(VIRTUAL) 8.09 0.00 816.18 1.18 0.00 4.57 815.03 0.03 0 11:55 0 00:00 0.00 0.00 BREC, PA Pipe Input SN Element ID Length Inlet Inlet Outlet Outlet Total Average Pipe Pipe Pipe Manning's Entrance Exit/Bend Additional Initial Invert Invert Invert Invert Drop Slope Shape Diameter or Width Roughness Losses Losses Losses Flow Elevation Offset Elevation Offset Height (ft) (ft) (ft) (ft) (ft) (ft) N (in) (in) (cfs) 1 SCM-BARREL 10.00 815.25 0.00 815.00 0.00 0.25 2.5000 CIRCULAR 15.000 15.000 0.0120 0.5000 0.5000 0.0000 0.00 2 SITE-ABOVE-GROUND-LINK(VIRTUAL) 10.00 815.00 0.00 814.75 0.00 0.25 2.5000 CIRCULAR 18.000 18.000 0.0120 0.5000 0.5000 0.0000 0.00 BREC,PA Flap No. of Gate Barrels No No BREC, PA Pipe Results SN Element Peak Time of Design Flow Peak Flow/ Peak Flow Travel Peak Flow Peak Flow Total Time Froude Reported ID Flow Peak Flow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition Occurrence Ratio Total Depth Ratio (cfs) (days hh:mm) (cfs) (ft/sec) (min) (ft) (min) 1 SCM-BARREL 8.09 0 11:56 11.06 0.73 6.65 0.03 1.21 0.97 0.00 Calculated 2 SITE-ABOVE-GROUND-LINK(VIRTUAL) 8.09 0 11:57 17.99 0.45 6.95 0.02 0.94 0.63 0.00 Calculated BREC, PA Storage Nodes Storage Node : INFILTRATION Input Data Invert Elevation (ft)............................................................................... 813.00 Max (Rim) Elevation (ft)........................................................................ 819.00 Max (Rim) Offset (ft)............................................................................. 6.00 Initial Water Elevation (ft)..................................................................... 813.00 Initial Water Depth (ft).......................................................................... 0.00 Ponded Area (ft2)................................................................................... 0.00 Evaporation Loss................................................................................... 0.00 Storage Area Volume Curves Storage Curve : INFILTRATION Stage Storage Storage Area Volume (ft) (ft2) (ft') 0 240 0 0.5 240 120 0.51 310 122.75 3 310 894.65 3.01 2083 906.62 4 2906 3376.18 5 4331 6994.68 6 6182 12251.18 BREC,PA Storage Area Volume Curves Storage Volume (ft3) 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 6,000 Storage Area (ft') Storage Area — Storage Volume BREC, PA Storage Node : INFILTRATION (continued) Outflow Weirs Outflow Orifices SN Element Weir Flap Crest Crest Length Weir Total Discharge ID Type Gate Elevation Offset Height Coefficient (ft) (ft) (ft) (ft) 1 EM-SPILLWAY Trapezoidal No 817.50 4.50 10.00 1.25 3.33 SN Element Orifice Orifice Flap Circular Rectangular Rectangular Orifice Orifice ID Type Shape Gate Orifice Orifice Orifice Invert Coefficient Diameter Height Width Elevation (in) (in) (in) (ft) 1 SCM-SECONDARY Bottom Rectangular No 36.00 36.00 817.00 0.63 Output Summary Results Peak Inflow (cfs).................................................................................... 8.65 Peak Lateral Inflow (cfs)........................................................................ 8.65 Peak Outflow (cfs)................................................................................. 8.14 Peak Exfiltration Flow Rate (cfm).......................................................... 0 Max HGL Elevation Attained (ft)............................................................ 817.35 Max HGL Depth Attained (ft)................................................................. 4.35 Average HGL Elevation Attained (ft)..................................................... 815.74 Average HGL Depth Attained (ft).......................................................... 2.74 Time of Max HGL Occurrence (days hh:mm)........................................ 0 11:56 Total Exfiltration Volume (1000-ft3)...................................................... 0 Total Flooded Volume (ac-in)................................................................ 0 Total Time Flooded (min)...................................................................... 0 Total Retention Time (sec).................................................................... 0 Soils Report BREC, P.A. Dollar General — Store #24556 16 V October 18, 2022 CATAWBA VALLEY ENGINEERING& TESTING Mr. Derek Goddard BREC, PA P.O. 1520 Meadow View Drive PO Box 747 Hickory, NC Hi28603 Wilkesboro, North Carolina 28697 derek@brec.biz 161 Lenoir Rhyne Blvd Hickory, NC 28602 Re: Seasonal High Water Table Analysis (SHWT) 828 578 9972 0 Proposed Dollar General Store 828 322 1801 F Mooresville Road and Briggs Road NC Firm No. C-3833 SC Firm No. 5201 Salisbury, Rowan County, North Carolina CVET Project Number: 22-552 Dear Mr. Goddard: Catawba Valley Engineering and Testing (CVET) is pleased to submit the results of the seasonal high-water table (SHWT) analysis performed for the proposed Dollar General Store site located at the above referenced address in Salisbury, North Carolina. It's our understanding that the SHWT analysis performed for this project is for the design purpose of constructing a new permanent pond. The contents of this report are provided for the use of BREC, PA and its approved affiliates, and are not intended to be used as the basis for design and construction for any other project. The contents of this report shall not be utilized by any other parties unless written permission is granted by CVET. CVET disclaims all liability from the misuse or reliance, by any such parties, of the contents brought forth in this report. TEST PROCUDURES AND FIELD SERVICES The SHWT analysis included review of the data collected from the subsurface exploration and geotechnical evaluation performed in June 2022 and drilling of an additional soil test boring in the proposed pond area during October 2022. Our interpretation of the SHWT is the upper limit of soil saturated with water for periods long enough for anaerobic conditions to affect soil color. Such periods result in iron (Fe) reduction within soils causing mottling or soil leaching to occur, typically resulting in a grayish color. Geotechnical Engineering Environmental Services Based upon our soil borings drilled to date, mottling was observed at CMT/Special Inspections approximately 5.5 to 6.0 feet below existing site grades with elevated soil Page 2 of 2 Mooresville Road and Briggs Road Salisbury, Rowan County, North Carolina CVET Project No. 22-552 moisture content observed in soil samples collected from approximately 10.0 to 20.0 feet below existing site grades. Groundwater was not observed in any of the test borings drilled during this evaluation, however each borehole was left open for only a short period of time during the drilling operation, so the detection of groundwater during this brief period is difficult. Also note that soil moisture and groundwater conditions vary depending on conditions such as temperature, precipitation and season. Therefore, soil moisture and groundwater location at other times of the year may vary from those observed at the time of this subsurface exploration and as described in this report. USGS 354057080362601, RO-149 (NC-193), Piedmont RS1 NR Barber (Regolith) is located approximately 2 miles northwest of the subject site. The well is approximately 24 feet in depth and had a documented high-water table of 4.99 feet below existing site grades on February 25, 2019. Based the information available, we conclude that the SHWT at the project site is approximately 6.0 feet below existing site. The testing results presented in this letter report are based on the specific boring locations (see Figures 1 and 2) within the proposed pond area as well as the southern portion of the subject site (test borings SHWT, B04, and B05) and do not reflect variations in subsurface conditions that may exist between test boring locations. We appreciate the opportunity to provide professional engineering services for your project. If you have any questions regarding the contents of this report, please feel free to contact us. Sincerely, ,,LI,,,,,, CATAWBA VALLEY ENGINEERING AND TESTING, P.C. - SEAL sOi 041419 :rr� James H. Carter Senior Geologist 10/18/2022 David M. LeGrand, Jr., PE President NC 041419 c. 1 1 � v'jeg70'�Z p p ti. Infiltration Report BREC, P.A. Dollar General — Store #24556 17 V August 18, 2022 CATAWBAVALLEY Mr. Justin Church, P.E. ENGINEERING & TESTING BREC, P.A. 1520 Meadowview Drive Wilkesboro, North Carolina 28697 PO Box 747 Hickory, NC 28603 Justin@brec.blz 161 Lenoir Rhyne Blvd Hickory, NC 28602 Hickory, Re: Double-RingInfiltrometer Tests Parcel ID #465A043 and 465AO44 828 578 9972 0 Mooresville Road and Briggs Road 828 322 1801 F Salisbury, Rowan County, North Carolina NC Firm No. C-3833 CVET Project Number: 22-808 SC Firm No. 5201 Dear Mr. Church: Catawba Valley Engineering and Testing (CVET) is pleased to submit the results of the Double -Ring Infiltrometer tests performed at the above referenced site located in Salisbury, North Carolina. CVET was requested to perform infiltration testing at the proposed drainage retention area to determine the in -situ infiltration rate of the soils. The contents of this report are provided for the use of BREC, P.A. and its approved affiliates, and are not intended to be used as the basis for design and construction for any other project. The contents of this report shall not be utilized by any other parties unless written permission is granted by CVET. CVET disclaims all liability from the misuse or reliance, by any such parties, of the contents brought forth in this report. TEST PROCUDURES AND FIELD SERVICES The double -ring infiltrometer method is a field measurement of infiltration rates of soils. A small metal ring is centered inside a larger outer metal ring. The two rings are driven 6 to 8 inches into the soil. Water maintained in the outer ring promotes one-dimensional, vertical flow beneath the inner ring. A constant water level is then maintained within the smaller, inner ring. The time corresponding to the change in water level within the inner ring is recorded until the rate of infiltration stabilizes. Test results are generally reported in inches or centimeters per hour. The tests were performed in general accordance with ASTM D3385. One (1) test was performed on August 3 and 4, 2022 at a test pit location Geotechnical Engineering excavated by BREC, P.A. personnel (see attached figure: test location 1) Environmental Services using a CAT 306 mini -excavator. The test pit location was provided by CMT/Special Inspections BREC, P.A. and located in the field by CVET personnel. The test pit was Page 2 of 2 Salisbury, Rowan County, North Carolina CVET Project No. 22-808 excavated to a depth of approximately 3.0 feet below existing site grades as requested by BREC, P.A.. A soil sample was collected from the subgrade of each test pit where the infiltration testing was conducted (approximately 3.5 to 4.5 feet below existing site grades). The samples were sealed in an airtight container and transported to CVET's laboratory in Hickory, North Carolina, where they were examined by a geotechnical engineer and subjected to USCS Soil Classification testing. Note that the soil samples will be discarded after 60 days from this report date, unless otherwise directed by BREC, P.A. FINDINGS AND CONCLUSIONS Laboratory testing for this portion of the study consisted of Soil Moisture Content (ASTM D2216), Grain Size Distribution (ASTM D422), and Atterberg limits for plasticity (ASTM D4318). Laboratory results indicate that the test pit subgrade soils mainly consist of sandy elastic silt (MH) with approximately 96 percent passing through the #200 Sieve. The plasticity index at the testing location was 31%. The soil laboratory results are attached. The infiltration test was run for a duration of approximately 8.0 hours at approximately 3.0 feet below existing site grades. The water level during the test was maintained at 14.0 inches. The infiltration rate at the test location was approximately 1.0" per hour (see attached infiltration rate chart). The testing results presented in this letter report are based on the specific testing location within the proposed drainage retention area and do not reflect variations in subsurface conditions that may exist between test locations. We appreciate the opportunity to provide professional engineering services for your project. If you have any questions regarding the contents of this report, please feel free to contact us. �i uu uCA ri. 5�5 fits Sincerely, ."'. SEAL ` CATAWBA VALLEY ENGINEERING AND TESTING, P.C.�O 041419 James H. Carter Senior Geologist Attachments: Figure Soil Laboratory Results Infiltration Rate Chart 8/18/2022 David M. LeGrand, Jr., PE President NC No.: 34514 CONCEPTUAL SITE PLAN CITY, STATE - STREET SALIABURY, ROWAN COUNTY, NC - MOORESVILLE RD PARCEL ID: 465A043 A, 465A044 DEVELOPER DESIGNER DATE 2/3/22 1 -A • AREA uu�pyi PROPOSED FA WELL IQI � — -----i • LOCATION s ( I ( N GENERAL NOTES. LEGEND 1. PRELIMINARY BOUNDARY IS BASED ON INFORMATION FROM PROPERTY EXISTING ASPHALT 7=1 PROPOSED HD ASPHALT APPRAISER AND SHALL BE USED FOR ILLUSTRATIVE PURPOSES ONLY. THIS PROPOSED CONCRETE = PROPOSED LD ASPHALT PLAN SHALL NOTBE INTENDEDTO CERTIFY THE ACCURACY OF EXISTING SURFACE OR SUBSURFACE CONDITIONS. ALL AREAS AND DIMENSIONS ARE S PROPOSED LANDSCAPING APPROXIMATE AND SHOULD BE VERIFIED BY ACTUAL SURVEY. SCALE: r' = To' 2. PROPOSED ACCESS LOCATIONS SHALL BE APPROVED BY REGULATORY (ON 8.5" x 1 Y) AGENCIES HAVING JURISDICTION. Particle Size Distribution Report U.S. SIEVE OPENING IN INCHES U.S. STANDARD SIEVE NUMBERS HYDROMETER 1 % in. % in. 3/8 in. #140 6 in. 3 in. 2 in. 1 in. % in. #10 #20 # 0 #40 #60 #100 #200 100 90 80 70 w 60 Z Z 50 w U T- a 40 30 20 10 0 100 10 1 0.1 0.01 0.001 GRAIN SIZE - mm. % Gravel % Sand % Fines %+3" Coarse Fine Coarse Medium Fine Silt Clay 0 0 0 0 0 4 96 Source Sample # Depth/Elev. Date Sampled USCS Material Description NM % LL PL O Infiltration Test 6022 3.5-4.5 08/08/22 Mfl Orange Elastic SILT 35.0 77 46 Client Teramore Develo ement, LLC Catawba Valley Engineering & Testing, P.C. Hickory, North Carolina Project Teramore Mooresville Road Test Pits Project No. 22808 Figure Tested By: SPC Checked By: SPC 50 40 20 10 LIQUID AND PLASTIC LIMITS TEST REPORT Dashed line indicates the approximate upper limit boundary for natural soils G"o • CL-ML ML or OL MH or OH 10 20 30 40 50 60 70 80 90 100 110 LIQUID LIMIT SOIL DATA NATURAL SAMPLE DEPTH WATER PLASTIC LIQUID PLASTICITY SYMBOL SOURCE USCS NO. CONTENT LIMIT LIMIT INDEX N N N N • Infiltration 6022 3.5-4.5 35.0 46 77 31 MH Test Catawba Valley Client: Teramore Development, LLC Engineering & Testing, P.C. Project: Teramore Mooresville Road Test Pits Hickory, North Carolina Project No.: 22808 Figure Tested By: BV Checked By: Test 1: Infiltration Rates 35 31 31 30 30 30 30 30 — 28 25 25 25 C: 25 23 L 21 F 20 u C: 18 18 U� 17 17 17 17 L 16 d 15 v E 10 5 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Readings Taken After 0.5 Inch of Infiltration