SW6190102_Design Calculations_20220720

A=COM
SOF OPERATIONS ANNEX BUILDING
PN 92793
Civil Calculations
Final Submittal (NCDEQ) — 23 November 2021
Contents
1. Stormwater Report
2. Pre -Develop Hydrology Exhibit
3. Post -Develop Hydrology Exhibit
4. NCDEQ Discrete SCS Curve Number Method
5. NCDEQ SUPPLEMENT-EZ COVER PAGE
6. Army LID Planning and Cost Tool Report
7. Storm Drainage Calculations
a. Storm and Sanitary Analysis (SSA) Output
b. Stage -Storage Curve
c. HGL Profiles
Appendix A: Soil Survey
Appendix B: Applicable excerpts from "SOF Complex Phase 3" (SOF3)
Project, performed by Mason & Hanger
CAR'0.,
AL
43
AECOM Project: 60625564
SOF ANNEX - CIVIL FINAL Calculations. Page 1 of 44 1`23 NOV 20211

SOF OPERATIONS ANNEX BUILDING — Fort Bragg, North Carolina _
STORMWATER CALCULATIONS A=COM
Design By: MAG PN #: 92793
Checked By: BDF Date: 25 June 2021
STORMWATER REPORT — SOF OPERATIONS ANNEX BUILDING
PROJECT DESCRIPTION
This project (Annex Building) is located within the Aberdeen Training Facility at the Fort Bragg Army
Installation. The project area is located entirely within the site area of the recently constructed "SOF Special
Tactics Facility, Phase 3 PN 76514" (Phase 3). This project is a single building being developed to provide
additional support and space for the existing tactics facility.
The Phase 3 project was designed by Mason & Hanger in 2018 and permitted by North Carolina Department
of Environmental Quality (NCDEQ) in 2019, with construction completing in 2021. The Annex Building will
utilize and modify existing stormwater management systems of the Phase 3 facility to maintain compliance
with stormwater requirements.
The existing project site is entirely pre -developed, being within the Phase 3 project boundaries. Site
surfaces consist of turf grass and impervious pavements. The site is bound to the south and east by
buildings constructed during the Phase 3 project. The site is bound to the west and north by a 2H:1 V
vegetated slope constructed during the Phase 3 project. Topography primarily slopes to storm drainage
inlets installed in Phase 3 that are directed to an existing bioretention basin (Bioretention Basin #1). Existing
vegetated slope to the north and west is directed to an existing vegetated channel.
All drainage areas for the project are in the watershed of Rockfish Creek, Stream Index 18-31-1. Rockfish
Creek is of Classification C: Aquatic Life, Secondary Recreation, Freshwater, and within the Cape Fear
River Basin.
STORMWATER REQUIREMENTS
(1) — NCDEQ FIRST FLUSH: NCDEQ regulations require treatment of the runoff from a 1" depth storm
event. The Phase 3 project met this requirement with bioretention basins. NCDEQ regulations require
that the runoff from a 1" rainfall event be contained within the above -grade ponded area of a bioretention
basin, with a maximum ponded depth of 12".
(2) — FEDERAL EISA 438: As the project is a major Federal project, UFC 3-210-10 requires compliance
with EISA Section 438. Low -Impact Development (LID) measures must be utilized, to the maximum
extent technically feasible, to maintain the predevelopment hydrology of the property. To comply with
EISA 438, Option 1, the total volume of runoff from the 95th percentile storm event must be captured and
infiltrated on -site. The Phase 3 project met this requirement by providing additional storage volume for
infiltration below the normal soil depth of the bioretention basins. Bioretention Basin #1 has 60" of storage
volume available below the bioretention underdrain system.
(3) — LEED 4.1 — SUSTAINABLE SITES: RAINWATER MANAGEMENT: To obtain three points towards
the total LEED score, the project must retain on -site the runoff from the developed site for the 90th
percentile rainfall event using LID practices. Existing Bioretention Basin #1 will be utilized to retain all
runoff from the developed site for the 95th percentile storm (and all smaller storms).
Additionally, UFC 3-210-10 requires that all storm conveyance systems be adequate to carry the 10-year
storm event.
UK
SOF ANNEX - CIVIL FINAL Calculations, Page 2 of 44 [23 NOV 2021]

SOF OPERATIONS ANNEX BUILDING — Fort Bragg, North Carolina _
STORMWATER CALCULATIONS A=COM
Design By: MAG PN #: 92793
Checked By: BDF Date: 25 June 2021
METHODOLOGY AND ASSUMPTIONS
All methodology used to determine peak flows and storm event volumes follows the guidelines set by the
Corp of Engineers Wilmington District and NCDEQ.
Methodology and assumptions for this project matches those established by the Phase 3 project. This
allows for a fair comparison between pre- and post- development conditions, and calculations established
by Mason & Hanger during the design of the Phase 3 project. Runoff volumes were calculated utilizing
the Discrete SCS Curve Number Method, and TR-55 routing; pipe capacity and storm routing calculations
were determined utilizing Autodesk Storm and Sanitary Analysis.
Critical Design Storm Events
First Flush = 1" Rainfall Depth
95t" Percentile Storm Depth = 1.8" in 24-Hours (from Fort Bragg Installation Guide)
10-Year Storm Depth = 5.4" in 24-Hours
EXISTING CONDITIONS
The project site area is approximately 1.3 acres within the Phase 3 project site. The existing site is
developed and consists of a mix of pavements and turf grass. The topography for most of the site is
graded flat, with areas gently sloping to an existing storm sewer system. At the northern and western
extremities of the site, a 2H:1 V cut slope exists with a drainage channel at the bottom of the hill.
Soils consist of silty sands and are very well draining, Hydrologic Group A. Within pervious areas, most of
a first -flush rainfall event will immediately infiltrate into the ground.
For the purpose of stormwater calculations, the site has been subdivided into two major areas. The first
area (DA-1), is captured by a storm drainage system within the Phase 3 project and treated by
Bioretention Basin #1. The second drainage area (DA-2), bypasses around the project site.
A geotechnical investigative report was completed by AECOM in 2021 to verify soil conditions. Water
table is well below depth of excavations and infiltration basins.
PROPOSED CONDITIONS
The Annex Building project will add a new building, with supporting infrastructure including a retaining
wall, loading area, sidewalks, and utilities. Impervious area will be increased. All new impervious area will
be captured by new and existing storm sewer and treated by existing Bioretention Basin #1. Existing
drainage patterns will not be substantially altered.
DA-1 will capture all impervious runoff from the project and direct it to Bioretention Basin #1 for treatment.
Overflow structures at Bioretention Basin #1 will be altered from a 10" ponding depth to a 12" ponding
depth, to provide sufficient storage volume to fully capture the calculated 1" first flush within above -grade
2/3
SOF ANNEX - CIVIL FINAL Calculations, Page 3 of 44 [23 NOV 2021]

SOF OPERATIONS ANNEX BUILDING — Fort Bragg, North Carolina _
STORMWATER CALCULATIONS A=COM
Design By: MAG
Checked By: BDF
PN #: 92793
Date: 25 June 2021
storage. Bioretention Basin #1 will not need to be altered below grade. Sufficient storage volume is
already available within Bioretention Basin #1 to maintain full compliance with EISA 438, even with the
additional impervious area of this project.
TR-55 calculations are used for each subbasin to determine peak flows and verify adequacy of
downstream conveyance. Pipe sizes were confirmed using Autodesk Storm and Sanitary Analysis, using
minimum sizes as required by UFC 3-201-01. The results of stormwater conveyance are provided in
these calculations, including confirmation of hydraulic grade lines during a 10-year storm event.
STORMWATER MANAGEMENT
To verify compliance with NCDEQ first -flush requirements, the total runoff volume for DA-1 was
calculated using the Discrete SCS Curve Number Method. The total runoff volume will be contained
within the above ground ponded depth of Bioretention Basin #1. See NCDEQ worksheets within these
calculations for additional information.
To verify compliance with EISA 438 requirements, a TR-55 composite curve of DA-1 was developed to
determine the total runoff volume during a 1.8" storm event. This curve was routed through Bioretention
Basin #1 to confirm adequate basin volume and total capture. The following criteria were used to
determine the total volume of stormwater runoff: Hydrologic Soil Group A; average infiltration rate of 6
inches per hour; impervious depression storage of 0.2 inches. The 10-year, 5.4" storm event was also
routed through the control structure of Bioretention Basin #1 to verify adequacy and provide a comparison
of peak flows between pre- and post- development conditions. The existing structures and channels will
continue to be adequate, with reduced 10-year peak runoff rates as compared to a pre -development
condition.
Bioretention Area #1, constructed in Phase 3, consists of a volume of ponding storage (10" depth), a
section of engineered fill to promote infiltration and sediment removal (24" depth), and a layer of open
graded aggregate to provide additional storage (60" depth). Ponded storage will be increased to 12"
depth for this project. The design of Bioretention Area #1 was completed by Mason & Hanger for the
Phase 3 project and was based upon design criteria from Sustainable Landscape Systems for Managing
Storm Water 2" d Edition, developed by Ohio State University Extension. All drainage from the project site
enters the bioretention area above grade via storm sewer.
As an additional check to confirm compliance with EISA 438 requirements, storage volume provided
within Bioretention Basin #1 was compared against the minimum required volume calculated by the Army
LID Planning and Cost Tool. This tool was developed to MILCON standards for projects within the
jurisdiction of the Army, to quickly determine the minimum volume required to be store and infiltrated
onsite for compliance with EISA 438.
For storm events greater than the 95t" percentile event, runoff will bypass through an overflow structure in
Bioretention Basin #1 to the existing outfall channel. Outfall channel is adequate and was provided with
channel protection as part of the Phase 3 project.
KKK]
SOF ANNEX - CIVIL FINAL Calculations, Page 4 of 44 [23 NOV 2021]

$ 5 70 ( 1 7 2 ) 7, ( 1 7 ( 5, 2 5 0 &&$.1 4 8$' 5$1
6.- � 212' .&$/ 68 69� � 1257- &$521,1$
skus 2 USGS S—To"p"o 5
—.ft— 7. -0 , 87( 6(5,(6
6&$1 124000
0 &&$.l &
2013
SOF ANNEX - CIVIL FINAL Calculations, Page 5 of 44 [23 NOV 2021]

V
M
J
H
G
E
C
3
A
UNCLASSIFIEDHFOR OFFICIAL USE ONLY
nnr% 1�^-r
US Army Corps
of Engineers
�yY�Yb�
50' 25' 0 50' 100'
GRAPHIC SCALES CG711
F T F
UNCLASSIFIEDHFOR OFFICIAL USE ONLY

M
D
3
A
UNCLASSIFIEDHFOR OFFICIAL USE ONLY
P ROJ E CT US Army Corps
EXISTING of Engineers
BIORETENTION
AREA #1
TOTAL POST DA-1
A = 5.99 ac.
EXISTING "HW-5"
4OUTFALL (SOF3)
50' 25' 0 50' 100'
GRAPHIC SCALES CG712
F T F
UNCLASSIFIEDHFOR OFFICIAL USE ONLY

Discrete SCS Curve Number Method (NCDEQ Stormwater Manual 3.3.2) - UPDATED FOR SOF ANNEX
Location: Bioretention Area 1
Soil Group: A
Predevelopment BUA
Area
0
acres
0
sf
CN
98
S
0.20
is
0.04
in
P
1
in
Q
0.79
in
V
I 0
cf
Predevelopment Open Area
Area
5.94
acres
258605
sf
CN
30
S
23.33
is
4.67
in
P
1
in
Q
0.00
in
V
I 0
cf
Predevelopment Totals
Area
5.94
acres
CN
30
Volume
0
cf
(SOF ANNEX PRE-DEV)
Phase 3 Developed BUA
Area
3.63
acres
158,071
sf
CN
98
S
0.20
is
0.04
in
P
1
in
Q
0.79
in
V
1 10418
cf
(SOF ANNEX PRE-DEV)
Phase 3 Developed BUA
Area
2.31
acres
100,534
sf
CN
39
S
15.64
is
3.13
in
P
1
in
Q
0.00
in
V
I 0
cf
(SOF ANNEX PRE-DEV)
Phase 3 Totals
Area
5.94
acres
CN
75
Volume
10,418
cf
Date
6/25/2021
(IMPERVIOUS)
BUA w/ SOF Annex
Area
4.11
acres
179,218
sf
CN
98
S
0.20
is
0.04
in
P
1
in
Q
0.79
in
V
I 11812
cf
(PERVIOUS)
Open Area w/ SOF Annex
Area
1.88
acres
81,678
sf
CN
39
S
15.64
is
3.13
in
P
1
in
Q
0.00
in
V
I 0
cf
SOF Annex Totals
Area
5.99
acres
CN
80
Volume
11,812
cf
Storage Required 11,812 cf
Surface Area 13,572 sf
Riser 12 in
Storage Provided 13,572 cf
Note: Runoff depth of CN <= 70 set to 0.00 for 1.0" rainfall event based on upon TR55 Urban Hydrology for
Small Watersheds Table 2-1
SOF ANNEX - CIVIL FINAL Calculations, Page 8 of 44 [23 NOV 2021]

SUPPLEMENT-EZ COVER PAGE
FORMS LOADED
PROJECT INFORMATION
1 Project Name
2 Project Area ac
SOF OPERATIONS_ ANNEX
5.99 -
3
Coastal Wetland Area a_c
0
4
Surface Water Area ac
0
5
Is this ro'ec! t High or Low Density?
Hi h
6
Does this project use an off -site SCM?
No
COMPLIANCE WITH 02H .1003(4)
7
Width of vegetated setbacks provided feet)
N/A
8
Will the vegetated setback remain vegetated?
N/A ~
9
_ _
If BUA is proposed in the setback does it meet NCAC 02H.1003(4Zc-d ?
N/A
10
Is streambank stabilization proposed on this project?
_
No
NUMBER AND TYPE OF SCMs:
11
Infiltration System
12
Bioretention Cell
1 -
13
Wet Pond
14
Stormwater Wetland
15
Permeable Pavement
16
Sand Filter
17
Rainwater Harvesting RWH
18
Green Roof
19
Level Spreader -Filter Strip LS-FS
20
Disconnected Impervious Surface DIS
21
Treatment Swale
22
Dry Pond
23
StormFilter
24
Silva Cell
25
Bayfilter
26
Filterra
FORMSLOADED
DESIGNER CERTIFICATION
27
Name and Title:
Brian D. Fisher
28
Organization:
AECOM
29
Street address:
10 S. Jefferson, Suite 1600
30
City_, State, Zip:
Phone numbers :
Email:
Roanoke, VA 24011
31
540-857-3226
32
[e-mail]
Certiliication Statement
1 certify, under penally of law that this Supplement-EZ form and all supporting information were prepared under my direction or supervision, that the
information provided in the form is, to the best of my knowledge and belief. true, accurate, and complete; and that the engineering plans,
specifications, operation and maintenance agreements and other supporting information are consistent with the information provided here
o� E'S S �O,�y
SEAL
046338
G I N Et. ;
�DUGLAS Seal
,-eQ*._0Z -
Signature of De er
11 /1.0§
Date
SOF ANNEX - CIVIL FINAL Calculations, Paqe 9 of 44 123 NOV 20211

DRAINAGE AREAS
1
Is this a high density project?
Yes
2
If so, number of drainage areas/SCMs
1
3
Does this project have low densit areas?
No
4
If so, number of low density drainage areas
0
5
Is all/part of this project subject to previous rule
versions?
No
FORMS LOADED
DRAINAGE AREA INFORMATION
Entire Site
1
4
Type of SCM
Bioretention
5
Total drainage area (sq ft)
260924
6
Onsite drainage area (sq ft)
260924
7
Offsite drainage area (sq ft)
0
8
Total BUA in project (sq ft
179218 sf
9
New BUA on subdivided lots (subject to permitting)
sq ft
sf
10permitting)
New BUA not on subdivided lots (subject to
(sf)
Offsite BUA (sq ft)
sf
11
sf
12
Breakdown of new BUA not on subdivided lots:
- Parking (sq ft
84793 sf
- Sidewalk (sq ft
6709 sf
- Roof (sq ft
87716 sf
- Roadway s ft
sf
- Future (sq ft
sf
- Other, please specify in the comment box
below (sq ft
sf
13
New infiltrating permeable pavement on
subdivided lots (sq ft)
sf
14
New infiltrating permeable pavement not on
subdivided lots (sq ft)
Existing BUA that will remain (not subject to
s ft
sf
15permitting)
sf
16
Existing BUA that is already permitted (sq ft
158071 sf
17
Existing BUA that will be removed (sq ft
sf
18
1 Percent BUA
69%
19
Design storm inches
1.0 in
20
Design volume of SCM cu ft
13572 cf
21 Calculation method for design volume
ADDITIONAL INFORMATION _
Please use this space to provide any additional information about the
22 drainage area(s):
Discrete SCS CN
SOF ANNEX - CIVIL FINAL Calculations, Page 10 of 44 [23 NOV 2021]

BIORETENTION CELL
1
Drainage area number
1
2
Minimum required treatment volume cu ft
11812 cf
GENERAL MDC FROM 02H .1050
3
Is the SCM sized to treat the SW from all surfaces at build -out?
Yes
4
Is the SCM located away from contaminated soils?
Yes
5
What are the side slopes of the SCM (H:V)?
3:1
6
Does the SCM have retaining walls, gabion walls or other engineered
side slopes?
No
7
Are the inlets, outlets, and receiving stream protected from erosion
(10-year storm)?
Yes
8
Is there an overflow or bypass for inflow volume in excess of the
design volume?
Yes
g
lWhat is the method for dewatering the SCM for maintenance?
Other
10
If applicable, will the SCM be cleaned out after construction?
Yes
11
Does the maintenance access comply with General MDC (8)?
Yes
12
Does the drainage easement comply with General MDC (9)?
Yes
13
If the SCM is on a single family lot, does (will?) the plat comply with
General MDC (10)?
Yes
14
Is there an O&M Agreement that complies with General MDC (11)?
Yes
15
Is there an O&M Plan that complies with General MDC (12)?
Yes
16
1 Does the SCM follow the device specific MDC?
Yes
17
lWas the SCM designed by an NC licensed professional?
Yes
BIORETENTION
CELL MDC FROM 02H .1052
18
SHWT elevation (fmsl)
428.00
19
Bottom of the bioretention cell (fmsl)
442.00
20
Ponding depth of the design storm (inches)
12 in
21
Surface area of the bioretention cell (square feet)
13572 sf
22
Design volume of SCM cu ft
13572 cf
23
Ps the bioretention cell used for peak attenuation?
Yes
24
1 Depth of peak attenuation over planting surface (in)
25
Height of peak attenuation outlet above the planting surface (in)
26
Infiltration rate of the in situ soil (inch/hour)
14.4 in/hr
27
Diameter of the underdrain pipes (if applicable)
28
Does the design include Internal Water Storage (IWS)?
Yes
29
if so, elevation of the top of the IWS (fmsl)
444
30
Elevation of the planting surface (fmsl)
447
31
What type of vegetation will be planted? (grass, trees/shrubs,
other)?
Other
32
1 Media depth (inches)
30 in
33
Percentage of medium to coarse washed sand by volume
85%
34
Percentage of fines (silt and clay) by volume
10%
35
Percentage of organic matter by volume
5%
36
Type of organic material
Engineered Fill
37
Phosphorus Index (P-Index) of media (unitless)
10
38
Will compaction be avoided during construction?
Yes
39
lWill cell be maintained to a one inch/hour standard?
Yes
40
Depth of mulch, if applicable (inches)
41
Type of mulch, if applicable
42
How many clean out pipes are being installed?
43
Type of pretreatment that will be used:
ADDITIONAL INFORMATION
44 Please use this space to provide any additional information about the
bioretention cell(s):
Minimum 3' sod
strip. All outlet
headwalls to cell
have rip -rap outlet
protection per
NCDEQ
I requirements.
This is an existing bioretention cell. The outlet struture will be raised 2
inches to allow for a maximum ponding of 12 inches. See original
biorentional design information provided under the separate, and previously
constructed, "SOF Complex Phase 3" project. Applicable excerpts of the
originial design calculations are provided in Appendix.
SOF ANNEX - CIVIL FINAL Calculations, Page 11 of 44 [23 NOV 2021]

Army LID Planning and Cost Tool Report
PROJECT INFO
SITE INFO AND EISA VOLUME
Date
6 / 25 / 2021
REQUIREMENT
Army Command
Project limit of disturbance (ac) 5.99
IMCOM
Army Installation
95% rainfall depth (in) F 1.8
Fort Bragg
Soil type Sandy
Project name
Ft. Bragg - SOF Annex
Pre -Fin
Project description
Hydrologic Soil Group (HSG) A
New building, sidewalks and service road
Pre -project curve number (CN) 30
with loading area.
_
Post -project curve number (CN) 79
User Name
MAG
Pre -project runoff volume (cf) 0
Master Planner
AECOM
Post -project runoff volume (cf) 8908
EISA Section 438 retention volume 8908
requirement (cf)
LID PLANNING SUMMARY
Structural BMP
Surface area
Runoff volume Non-structural BMP
(sf)
retained (c fl
Bioretention:
13572
16222 Veg. Filter Strip (Slope >2%, Short Grass):
Swale:
0 Veg. Filter Strip (Slope >2%, Tall Grass):
Permeable Pavement:
0
0 Veg. Filter Strip (Slope <2%, Short Grass):
Rainwater Harvesting:
0
0 Veg. Filter Strip (Slope <2%, Tall Grass):
Green Roof:
0
0 Reforestation (Trees - Short Grass):
Infiltration Practice:
0
0 Reforestation (Trees - Shrubs and Tall Grass):
Total retention volume
provided by BMPs (co: 16222
Project complies with EISA Section 438.
LID COST SUMMARY
Surface
area (ac)
0.00
0.00
0.00
0.00
0.00
0.00
SOF ANNEX - CIVIL FINAL Calculations, Page 12 of 44 [23 NOV 2021]

AECOM Civil Calculations SOF OPERATIONS
10 S. Jefferson Street Storm Drainage ANNEX BUILDING
Roanoke, Virginia 24011 g Ft. Bragg, North Carolina
(Note: The following output was generated using SSA 2020.)
Autodesk® Storm and Sanitary Analysis 2016 - Version 13.2.147 (Build 0)
----------------------------------------------------------------------------------------
*******************
Project Description
*******************
File Name ................. SOF3 SSA POSTDEV MODEL.SPF
****************
Analysis Options
****************
Flow Units ................ cfs
Subbasin Hydrograph Method. SCS TR-55
Time of Concentration...... SCS TR-55
Link Routing Method ....... Kinematic Wave
Storage Node Exfiltration.. Constant rate, free surface area
Starting Date ............. APR-13-2020 00:00:00
Ending Date ............... APR-14-2020 00:00:00
Report Time Step .......... 00:05:00
*************
Element
*************
Count
Number
of rain gages ...... 1
Number
of subbasins ....... 7
Number
of nodes ........... 9
Number
of links ........... 7
****************
Subbasin Summary
****************
Subbasin
Total
Peak Rate
Area
Factor
ID
acres
------------------------------------------
DA-1A
1.67
484.00
DA-1B
0.42
484.00
DA-1C
0.66
484.00
DA-1D
1.30
484.00
DA-1E
1.16
484.00
DA-1F
0.77
484.00
DA-2
2.21
484.00
************
Node Summary
************
Node
Element
Invert
Maximum
Ponded External
ID
Type
Elevation
Elev.
Area Inflow
ft
ft
ft2
------------------------------------------------------------------------------
CB-10
JUNCTION
454.43
461.65
0.00
CB-11
JUNCTION
454.22
461.50
0.00
CB-13
JUNCTION
452.73
460.50
0.00
CB-7
JUNCTION
455.90
464.70
0.00
CB-8
JUNCTION
455.43
463.00
0.00
CB-9
JUNCTION
454.66
462.30
0.00
Outfall-01
OUTFALL
443.60
449.29
0.00
1/6
SOF ANNEX - CIVIL FINAL Calculations, Page 13 of 44 [23 NOV 2021]

AECOM Civil Calculations SOF OPERATIONS
10 S. Jefferson Street Storm Drainage ANNEX BUILDING
Roanoke, Virginia 24011 Ft. Bragg, North Carolina
Outfall-02 OUTFALL 460.00 460.00 0.00
Bioret-01 STORAGE 438.50 450.00 0.00
************
Link Summary
************
Link
From Node
To Node
Element
Length
Slope
Manning's
ID
Type
ft
o
Roughness
--------------------------------------------------------------------------------------------
Pipe-07
CB-7
CB-8
CONDUIT
95.7
0.4911
0.0130
Pipe-08
CB-8
CB-9
CONDUIT
152.3
0.5054
0.0130
Pipe-09
CB-9
CB-10
CONDUIT
47.6
0.4833
0.0130
Pipe-10
CB-10
CB-11
CONDUIT
40.5
0.5189
0.0130
Pipe-11
CB-11
CB-13
CONDUIT
298.3
0.4996
0.0130
Pipe-13
CB-13
Bioret-01
CONDUIT
56.9
4.7970
0.0130
Orifice-01
Bioret-01
Outfall-01
ORIFICE
*********************
Cross Section Summary
*********************
Full Flow
Design
Depth
/
No. of
Cross
Hydraulic
Flow
Link ID Shape
Width
Sectional
Diameter
Barrels
Radius
Capacity
Area (ft2)
(ft)
(cfs)
Pipe-07 CIRCULAR
1.50
1.50
1
1.77
0.38
7.36
Pipe-08 CIRCULAR
1.50
1.50
1
1.77
0.38
7.47
Pipe-09 CIRCULAR
2.00
2.00
1
3.14
0.50
15.73
Pipe-10 CIRCULAR
2.00
2.00
1
3.14
0.50
16.30
Pipe-11 CIRCULAR
2.00
2.00
1
3.14
0.50
15.99
Pipe-13 CIRCULAR
2.00
2.00
1
3.14
0.50
49.55
**************************
Volume
Depth
Runoff Quantity Continuity
**************************
acre-ft
inches
Total Precipitation ......
---------
3.743
-------
5.484
Surface Runoff ...........
0.169
0.247
Continuity Error (%) .....
-0.001
**************************
Volume
Volume
Flow Routing Continuity
**************************
acre-ft
Mgallons
External Inflow ..........
---------
0.000
---------
0.000
External Outflow .........
0.474
0.155
Initial Stored Volume ....
0.000
0.000
Final Stored Volume ......
0.373
0.122
Continuity Error (%) .....
0.452
2/6
SOF ANNEX - CIVIL FINAL Calculations, Page 14 of 44 [23 NOV 2021]

AECOM Civil Calculations SOF OPERATIONS
10 S. Jefferson Street Storm Drainage ANNEX BUILDING
Roanoke, Virginia 24011 g Ft. Bragg, North Carolina
Composite Curve Number Computations Report
******************************************
-----------------
Subbasin DA-lA
-----------------
Area
Soil
Soil/Surface Description
(acres)
Group
CN
----------------------------------------------------------------------------------------
> 75% grass cover, Good
0.35
A
39.00
Paved parking & roofs
1.31
A
98.00
Composite Area & Weighted CN
1.66
85.56
-----------------
Subbasin DA-lB
-----------------
Area
Soil
Soil/Surface Description
(acres)
Group
CN
----------------------------------------------------------------------------------------
> 75% grass cover, Good
0.08
A
39.00
Paved parking & roofs
0.35
A
98.00
Composite Area & Weighted CN
0.43
87.02
-----------------
Subbasin DA-lC
-----------------
Area
Soil
Soil/Surface Description
(acres)
Group
CN
----------------------------------------------------------------------------------------
> 75% grass cover, Good
0.35
A
39.00
Paved parking & roofs
0.66
A
98.00
Composite Area & Weighted CN
1.01
77.55
-----------------
Subbasin DA-lD
-----------------
Area
Soil
Soil/Surface Description
(acres)
Group
CN
----------------------------------------------------------------------------------------
> 75% grass cover, Good
0.26
A
39.00
Paved parking & roofs
0.86
A
98.00
Composite Area & Weighted CN
1.12
84.30
-----------------
Subbasin DA-lE
-----------------
Area
Soil
Soil/Surface Description
(acres)
Group
CN
----------------------------------------------------------------------------------------
> 75% grass cover, Good
0.23
A
39.00
Paved parking & roofs
0.93
A
98.00
Composite Area & Weighted CN
1.16
86.30
-----------------
Subbasin DA-lF
-----------------
Area
Soil
Soil/Surface Description
----------------------------------------------------------------------------------------
(acres)
Group
CN
> 75% grass cover, Good
0.74
A
39.00
Paved parking & roofs
0.04
A
98.00
Composite Area & Weighted CN
0.78
42.03
3/6
SOF ANNEX - CIVIL FINAL Calculations, Page 15 of 44 [23 NOV 2021]

AECOM Civil Calculations SOF OPERATIONS
10 S. Jefferson Street Storm Drainage ANNEX BUILDING
Roanoke, Virginia 24011 g Ft. Bragg, North Carolina
----------------
Subbasin DA-2
----------------
Area
Soil
Soil/Surface Description
(acres)
Group
CN
----------------------------------------------------------------------------------------
Woods, Good
0.89
A
30.00
Paved parking & roofs
0.07
A
98.00
> 75% grass cover, Good
1.15
A
39.00
Pavement
0.10
A
98.00
Composite Area & Weighted CN
2.21
39.91
***********************
Subbasin Runoff Summary
***********************
--------------------------------------------------------------------------
Subbasin
Total
Total
Peak
Weighted
Time of
ID
Precip
Runoff
Runoff
Curve
Concentration
in
in
cfs
Number
days
hh:mm:ss
--------------------------------------------------------------------------
DA-lA
5.40
3.80
5.47
85.560
0
00:14:41
DA-lB
5.40
3.95
1.62
87.020
0
00:07:31
DA-lC
5.40
3.01
1.98
77.550
0
00:08:03
DA-lD
5.40
3.67
4.67
84.300
0
00:08:00
DA-lE
5.40
3.87
4.35
86.300
0
00:08:00
DA-lF
5.40
0.42
0.13
42.030
0
00:08:00
DA-2
--------------------------------------------------------------------------
5.40
0.33
0.21
39.910
0
00:15:00
******************
Node Depth Summary
******************
-----------------------------------------------------------------------------------------
Node
Average
Maximum
Maximum
Time
of Max
Total
Total
Retention
ID
Depth
Depth
HGL
Occurrence
Flooded
Time
Time
Attained
Attained
Attained
Volume
Flooded
ft
ft
ft
days
hh:mm
acre -in
minutes
hh:mm:ss
-----------------------------------------------------------------------------------------
CB-10
0.16
1.05
455.48
0
12:15
0
0
0:00:00
CB-11
0.19
1.35
455.57
0
12:15
0
0
0:00:00
CB-13
0.19
1.35
454.08
0
12:15
0
0
0:00:00
CB-7
0.14
0.96
456.86
0
12:15
0
0
0:00:00
CB-8
0.16
1.13
456.56
0
12:15
0
0
0:00:00
CB-9
0.16
1.13
455.79
0
12:15
0
0
0:00:00
Outfall-01
0.00
0.00
443.60
0
00:00
0
0
0:00:00
Outfall-02
0.00
0.00
460.00
0
00:00
0
0
0:00:00
Bioret-01
2.37
6.27
444.77
0
12:47
0
0
0:00:00
4/6
SOF ANNEX - CIVIL FINAL Calculations, Page 16 of 44 [23 NOV 2021]

AECOM Civil Calculations SOF OPERATIONS
10 S. Jefferson Street Storm Drainage ANNEX BUILDING
Roanoke, Virginia 24011 g Ft. Bragg, North Carolina
Node Flow Summary
*****************
------------------------------------------------------------------------------------
Node
Element
Maximum
Peak
Time of
Maximum
Time of Peak
ID
Type
Lateral
Inflow
Peak
Inflow
Flooding
Flooding
Inflow
Occurrence
Overflow
Occurrence
------------------------------------------------------------------------------------
cfs
cfs
days
hh:mm
cfs
days hh:mm
CB-10
JUNCTION
0.00
8.57
0
12:15
0.00
CB-11
JUNCTION
4.51
12.72
0
12:15
0.00
CB-13
JUNCTION
4.22
16.60
0
12:12
0.00
CB-7
JUNCTION
5.45
5.45
0
12:15
0.00
CB-8
JUNCTION
1.58
6.83
0
12:15
0.00
CB-9
JUNCTION
1.89
8.57
0
12:15
0.00
Outfall-01
OUTFALL
0.00
2.68
0
12:47
0.00
Outfall-02
OUTFALL
0.21
0.21
0
12:35
0.00
Bioret-01
STORAGE
0.13
16.68
0
12:14
0.00
********************
Storage Node Summary
********************
Time of
Maximum Average Maximum Maximum
Maximum Max Average Time of Max. Total
Ponded Ponded Ponded Storage Exfiltr tration
Storage Node ID Volume Ponded Ponded Volume Node ation Exfi RExfiltrated
Volume Volume ate Volume
(1000 (1000 Volume Outflow Rate R
ft3) M (Days ft3) M (cfs) (cfm) hh:mm:ss (1000 ft3)
hh:mm)
Bioret-01 30.176 42 0 12:47 11.415 16 2.68 40.08 0 : 0 0 : 0 0 33.069
***********************
Outfall Loading Summary
***********************
-----------------------------------------------
Outfall Node ID
Flow
Average
Peak
Frequency
Flow
Inflow
M
cfs
cfs
-----------------------------------------------
Outfall-01
23.19
0.90
2.68
Outfall-02
49.32
0.06
0.21
-----------------------------------------------
System
36.25
0.96
2.85
5/6
SOF ANNEX - CIVIL FINAL Calculations, Page 17 of 44 [23 NOV 2021]

AECOM
10 S. Jefferson Street
Roanoke, Virginia 24011
*****************
Link Flow Summary
*****************
Civil Calculations
Storm Drainage
SOF OPERATIONS
ANNEX BUILDING
Ft. Bragg, North Carolina
Time of
Peak Flow
Maximum
Peak Flow
Design
Ratio of
Ratio of
Total
Link ID
Element
Occurrence
Velocity
Length
during
Flow
Maximum/
Maximum
Time Sur-
Reported
Type
Attained
Factor
Analysis
Capacity
Design
Flow
charged
Condition
(days
(ft/sec)
(cfs)
(cfs)
Flow
Depth
(minutes)
hh:mm)
Pipe-07
CONDUIT
0 12:15
4.57
1.00
5.43
7.36
0.74
0.64
0
Calculated
Pipe-08
CONDUIT
0 12:15
4.81
1.00
6.82
7.47
0.91
0.75
0
Calculated
Pipe-09
CONDUIT
0 12:15
5.11
1.00
8.57
15.73
0.54
0.53
0
Calculated
Pipe-10
CONDUIT
0 12:15
5.25
1.00
8.57
16.30
0.53
0.52
0
Calculated
Pipe-11
CONDUIT
0 12:15
5.69
1.00
12.71
15.99
0.79
0.67
0
Calculated
Pipe-13
CONDUIT
0 12:12
14.20
1.00
16.61
49.55
0.34
0.40
0
Calculated
Orifice-01
ORIFICE
0 12:47
2.68
********************************
Highest Flow Instability Indexes
********************************
Link Pipe-13 (1)
qPOST-DEV Outfall Quo = 2.7 cfs
Analysis began on: Fri Jun 18 14:38:23 2021 < PRE-DEV Q10 = 6.25 cfs
Analysis ended on: Fri Jun 18 14:38:26 2021
Total elapsed time: 00:00:03 (Therefore ... acceptable.
6/6
SOF ANNEX - CIVIL FINAL Calculations, Page 18 of 44 [23 NOV 2021]

Storage Curve
Depth vs. Volume Curve
Volume (ft')
12
it
10
9
8
7
t 6
a
d
5
4
12
0

Profile Plot
Storm Drainage System
472
----- :---
--- -- - - - - -------- • - - - - --------L--
---- - - - - --------j------•------•-------L------L------------j-------j------•-------L------L------------j-------j------•------L------L------------
--- ----------- j------------- -L------L----
--'- - - - -- ------j------•---
471
---�-r-----�------T------T------r------r------r-----�------T------T------T------r------r-
� -�--
--------- --
-�--
-T-- -r---- -r---- � -�------T------T-- -r-- -r-- � -�--- -�--- -�------T------r------r------r
--- -- ------ I -- ----------- -- -
-----�------�- -T-
---- '
470
I
___ULI______
___________________L______L______I______
_
____ ______
j ______ I ______ ______ L ____________ ______ j ______ I ______ ______ L ____________--- _____ j ______ j ______ I ______ ______ ____________
j ______ j ______ I ___
I I I I I
I co
I I I I I I I
I I
I I I I I I I I I I I I I I I I I
I I I I
469
- T r
I
p
468
___H_______J______J______1______L__lj__l______'______J______J______1______1______L______ll___________J___.4_J______1___
pq
I I I I I
I I I I
I I I I I I I
I I
_L______l____________J______J______1______L______l____________J______J______J______1______L______l______'______J______J______1___
I I I I I I I I I I I I I I I
I I I
467
_________-______T______T______r__
I I I I I
_______,____________T______T______T______r______r_
I I I I I I I
I I
__________________T____r____________,____________,______T______r____________,____________�______I-______T______r______-__
I
I I I I I M
t__,______I-______T______T___
H
i
C]
Ly
Ogg
___
_ ___ _� ___
__ ___ ___ ___ ___ ___ __H
I I I
__ ___ _�
__ ___ ______ __ ___ ___ ___ ___ ___ __ ___ ___ ___ ___ ___ ___ �
I I I I I I I I I I I I I I
__ ___ ___ ___
I I I
I I
H
'
464
---
I I I � I
I
----T------r---- -r---------
I I I
____ '
_________
I -�--
41
I I I I I I I I I I I I I I I I I H
___ _ _______ I __ ___ _________ __ __ I
I-- -T-- -r---- -r---- -�------T------T-- -r-- -r-- ---- ---- -1------T------r------r------r
____
-----------1- -T-
O 4
463
---
------------- •------ •------- `------ L
--- ' - -�
L L
-- - -`- - - - - - - - - ------ ----- ----- ----- ----- ------ -
'----- ------ ------
462
---
- -----
I I I I I I I
1------ T------ r------ r------- --- �------ T------r------r------ r----- ------ ------I------T------r------r--,`$
--�------ ------ T---- - -T ---
461
___
I I I I I I I I I I I I
J------ J------ 1------ L------ l------
I I I I
I______ J______ J______ 1___
460
___
----------
459
___
I
458
-
Link ID Pi e-07
p
Link ID Pipe-08
I m
- - - +
457
---
k ID Pipe-09
ink ID Pi e-10
p LinkIDPipe-11
~____--;--_-s---
456
455
_____
454
_____
2 453
_____
uJ 452
_____
451
_____
450
_____
449
_____
448
-----
T
447
_____
446
_____
445
_____
444
_____
443
_____
442
_____
441
_____
440
_____
43g
_____
438
-----
-
437
436
___
1+00
1+20 1+40 1+60 1+80 2+00
2+20 2+40 2+60 2+80 3+00 3+20 3+40
3+60 3+80
4+00 4+20 4+40 4+60 4+80 5+00 5+20 5+40 5+60 5+80 6+00 6+20 6+40 6+60 6+80 7+00 7+20
7+40 7+60 7+80 8+00
Station (ft)
Node ID:
Rim (ft):
Invert (ft):
Min Pipe Cover (ft):
Max HGL (ft):
Link ID:
Length (ft):
Dia (ft):
Slope (ftlft):
Up Invert (ft):
Dn Invert (ft):
Max Q (efs):
Max Vel (ftls):
Max Deptf4;0,
CB-7
CB-8
CB-9
CB-10
CB-11
CB-13
Bioret-01
464.70
463.00
462.30
461.65
461.50
460.50
450.00
455.90
455.43
454.66
454.43
454.22
452.73
438.50
7.30
6.07
5.64
5.22
5.28
5.77
456.86
456.56
455.79
455.48
455.57
454.08
444.77
Pipe-07
Pipe-08
Pipe-09
Pipe-10
Pipe-11
Pipe-13
95.70
152.35
47.59
40.47
290.25
56.91
1.50
1.50
2.00
2.00
2.00
2.00
0.0049
0.0051
0.0048
0.0052
0.0050
0.0480
455.90
455.43
454.66
454.43
454.22
452.73
455.43
454.66
454.43
454.22
452.73
450.00
5.43
1 6.82
8.57
1 8.57
1 12.71
16.61
4.57
4.81
5.11
5.25
5.69
14.20
Mack Stnrm
and Sanitary Analvcic
1.12
1.05
1.03
1.35
0.80
SOF ANNEX - CIVIL FINAL Calculations, Page 20 of 44 [23 NOV 2021]

USDA United States
Department of
Agriculture
N RCS
Natural
Resources
Conservation
Service
A product of the National
Cooperative Soil Survey,
a joint effort of the United
States Department of
Agriculture and other
Federal agencies, State
agencies including the
Agricultural Experiment
Stations, and local
participants
Custom Soil Resource
Report for
Hoke County,
North Carolina
SOF Operations Annex
APPENDIX A: SOIL SURVEY
April 15, 2020
SOF ANNEX - CIVIL FINAL Calculations, Page 21 of 44 [23 NOV 2021]

UNCLASSIFIED//FOR OFFICIAL USE ONLY
3
64M 648590
35° 717'N
35° 78" N
Custom Soil Resource Report
Soil Map
648620 648650 648680
648710
648740
35° 717"N
7rb
648560 648590 648620 648650 648680 648710 649740
3 3
Map Scale: 1:1,290 if printed on A portrait (8.5" x 11") sheet.
Meters
N 0 15 30 60 90
Feet
0 50 100 200 30D
Map projecdon: Web Mercator Comer coordinates: WGS84 Edge tics: UTM Zone 17N WGS84
9
35° 7 8" N
UNCLASSIFIED//FOR OFFICIAL USE ONLY
SOF ANNEX - CIVIL FINAL Calculations, Page 22 of 44 [23 NOV 2021]

MAP LEGEND
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Q
Soil Map Unit Polygons
Soil Map Unit Lines
Soil Map Unit Points
Special
Point Features
Blowout
Borrow Pit
Clay Spot
k;
Closed Depression
`
Gravel Pit
Gravelly Spot
a
Landfill
Lava Flow
Marsh or swamp
+
Mine or Quarry
Miscellaneous Water
Perennial Water
ap
Rock Outcrop
Saline Spot
tr
Sandy Spot
4g�
Severely Eroded Spot
Sinkhole
Slide or Slip
0o
Sodic Spot
UNCLASSIFIED//FOR OFFICIAL USE ONLY
Custom Soil Resource Report
MAP INFORMATION
Spoil Area
The soil surveys that comprise your AOI were mapped at
1:24,000.
Stony Spot
Very Stony Spot
Warning: Soil Map may not be valid at this scale.
Wet Spot
Enlargement of maps beyond the scale of mapping can cause
Other
misunderstanding of the detail of mapping and accuracy of soil
.-
Special Line Features
line placement. The maps do not show the small areas of
contrasting soils that could have been shown at a more detailed
Water Features
scale.
Streams and Canals
Transportation
Please rely on the bar scale on each map sheet for map
i-r-r
Rails
measurements.
^.,
Interstate Highways
Source of Map: Natural Resources Conservation Service
US Routes
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Major Roads
Local Roads
Maps from the Web Soil Survey are based on the Web Mercator
projection, which preserves direction and shape but distorts
Background
distance and area. A projection that preserves area, such as the
®
Aerial Photography
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: Hoke County, North Carolina
Survey Area Data: Version 16, Sep 16, 2019
Soil map units are labeled (as space allows) for map scales
1:50,000 or larger.
Date(s) aerial images were photographed: Aug 13, 2014—Feb
4, 2017
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor
shifting of map unit boundaries may be evident.
10
UNCLASSIFIED//FOR OFFICIAL USE ONLY
SOF ANNEX - CIVIL FINAL Calculations, Page 23 of 44 [23 NOV 2021]

Custom Soil Resource Report
Map Unit Legend
Map Unit Symbol
Map Unit Name
Acres in AOI
Percent of AOI
CaB
Candor sand, 1 to 8 percent
slopes
5.3
86.0%
CaD
Candor sand, 8 to 15 percent
slopes
0.9
14.0%
Totals for Area of Interest
6.2
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
observed properties may extend beyond the limits defined for a taxonomic class.
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,
11
SOF ANNEX - CIVIL FINAL Calculations, Page 24 of 44 [23 NOV 2021]

Custom Soil Resource Report
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
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.
12
SOF ANNEX - CIVIL FINAL Calculations, Page 25 of 44 [23 NOV 2021]

Custom Soil Resource Report
Hoke County, North Carolina
CaB—Candor sand, 1 to 8 percent slopes
Map Unit Setting
National map unit symbol: w75q
Elevation: 80 to 330 feet
Mean annual precipitation: 38 to 55 inches
Mean annual air temperature: 59 to 70 degrees F
Frost -free period: 210 to 265 days
Farmland classification: Not prime farmland
Map Unit Composition
Candor and similar soils: 80 percent
Estimates are based on observations, descriptions, and transects of the mapunit.
Description of Candor
Setting
Landform: Ridges on marine terraces
Landform position (two-dimensional): Shoulder, summit
Landform position (three-dimensional): Crest
Down -slope shape: Convex
Across -slope shape: Convex
Parent material: Sandy and loamy marine deposits and/or eolian sands
Typical profile
A - 0 to 8 inches: sand
E - 8 to 26 inches: sand
Bt - 26 to 38 inches: loamy sand
E' - 38 to 62 inches: sand
B't - 62 to 80 inches: sandy clay loam
Properties and qualities
Slope: 1 to 8 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Somewhat excessively 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: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Available water storage in profile: Very low (about 2.9 inches)
Interpretive groups
Land capability classification (irrigated): None specified
Land capability classification (nonirrigated): 4s
Hydrologic Soil Group: A
Ecological site: Dry Sandy Upland Woodland (F137XY001 GA)
Hydric soil rating: No
13
SOF ANNEX - CIVIL FINAL Calculations, Page 26 of 44 [23 NOV 2021]

Custom Soil Resource Report
CaD—Candor sand, 8 to 15 percent slopes
Map Unit Setting
National map unit symbol: w75r
Elevation: 80 to 330 feet
Mean annual precipitation: 38 to 55 inches
Mean annual air temperature: 59 to 70 degrees F
Frost -free period: 210 to 265 days
Farmland classification: Not prime farmland
Map Unit Composition
Candor and similar soils: 80 percent
Estimates are based on observations, descriptions, and transects of the mapunit.
Description of Candor
Setting
Landform: Ridges on marine terraces
Landform position (two-dimensional): Backslope
Landform position (three-dimensional): Crest
Down -slope shape: Convex
Across -slope shape: Convex
Parent material: Sandy and loamy marine deposits and/or eolian sands
Typical profile
A - 0 to 8 inches: sand
E - 8 to 26 inches: sand
Bt - 26 to 38 inches: loamy sand
E' - 38 to 62 inches: sand
B't - 62 to 80 inches: sandy clay loam
Properties and qualities
Slope: 8 to 15 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Somewhat excessively 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: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Available water storage in profile: Very low (about 2.9 inches)
Interpretive groups
Land capability classification (irrigated): None specified
Land capability classification (nonirrigated): 4s
Hydrologic Soil Group: A
Ecological site: Dry Sandy Backslope Woodland - PROVISIONAL
(F137XY004GA)
Hydric soil rating: No
14
SOF ANNEX - CIVIL FINAL Calculations, Page 27 of 44 [23 NOV 2021]

�I
Mason&Hanger
ADay&Zimmer .Ca pa y
SOF STF Phase 3
Fort Bragg, Hoke County, North Carolina
APPENDIX B: Applicable excerpts from "SOF Complex
Phase 3" (SOF3) Project, performed by Mason & Hanger
PREDEVELOPMENT MAP
Mason & Hanger Page - a.2 -
SOF ANNEX - CIVIL FINAL Calculations, Page 28 of 44 [23 NOV 2021]

_ _
77 7� \77-1-,—,\�J��7/llll—��_--—
/ ✓ .. L..l, .Lr� 1' ./, ,/ .� L 4, � ./ , o a � ,l° �
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\ I I • I I / / l /: l l l l / l l l l l / / / / / / / I I I I I \ V A V A A Av v ��� '— / / / /" / ♦ / /l � _ � /� J/II / ,<
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// /,. /� l I I l �/ l/ / l l l l l l / l l I I I I I I I I I � \ \ I I � I I I I I �� // ///■� '�/ I I /
// / ■ / ■ / p�� / Y / / ////// / / / / / / / / I � I I I I I I II I I I I V V A \ I I I / � / I I I I --�� // / // // // / / / /. �''� �f /l I I xl /
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FRIE a■■! r..a..�..�..I �..1.. �....�....�....................�...\ .1...................... m
/ Po.... P■ " / .... ............... ... .... 4... . .....\•• \ ..
DAA
---
�471-
PRE -CONSTRUCTION
HYDROLOGY
DRAINAGE AREA AREA (ACRES) CN 010(CFS) Q25(CFS)
DA1 0.17 36 0.00 0.00
DA2 1.29 36 0.00 0.16
DA3 0.94 36 0.00 0.11
DA4 10.89 36 0.26 1.23
DA5 1.05 36 0.07 0.27
•�o
�• \ ,6 ••.• C \ \Ro.o�.°>"A�,� tea, t ) �\
%V A '�� \\ �`` — _,,, tiy�'• •♦ x••••• / ,i /,6 // /� / // yam♦ �/"� // /���// /II \L�' //— _ ---�\
/e% /pbz / // J / \ /�/ ♦�• �--'' i�'i�/i �/ �.sr/ // /� // /—ice \ � \ /
411
\ \—� I !� `--J `- ?1"0<'� • •�/ / / / // \ i� // /'♦i ��'/' �' /—' i� �i' �// /� /—` \\\\ I ----
\) `- — —" —1 — / III.•. �.,, / �; .��":. r..s Jam/ -
o_
411
v _ rd-
--
/ ,.,d,„�
50' 25' 0 50' 100' 150'
/ / / / �� // // GRAPHIC SCALE 1" 50' 0" N
US Army Corps
of Engineers,
a
w
0
0
H
m
X
w
Y
0
0
J
0
}
0
w
a
0
w
w
0
LU
a
IL i
GEOGRAPHIC COORDINATE DATA f1 Cq
HORIZONTAL DATUM: a�0R'0pEssi00
li':
NORTH CAROLINA STATE PLANE, NAD83.
VERTICAL DATUM: NAVD88. os9gL ° SHEET ID
'%�/ // /,•"°/ //'"/ // MEASURE:UNITS OF FEET.
xp COORDINATES OWN IN FORMAT OFE•LEPe CG j L
/ EASTING, NORTHING AND ELEVATION.
SOF ANNEX - CIVIL FINAL Calculations, Page 29Pt#,14Ry2T, jf E
•�o
�• \ ,6 ••.• C \ \Ro.o�.°>"A�,� tea, t ) �\
%V A '�� \\ �`` — _,,, tiy�'• •♦ x••••• / ,i /,6 // /� / // yam♦ �/"� // /���// /II \L�' //— _ ---�\
/e% /pbz / // J / \ /�/ ♦�• �--'' i�'i�/i �/ �.sr/ // /� // /—ice \ � \ /
411
\ \—� I !� `--J `- ?1"0<'� • •�/ / / / // \ i� // /'♦i ��'/' �' /—' i� �i' �// /� /—` \\\\ I ----
\) `- — —" —1 — / III.•. �.,, / �; .��":. r..s Jam/ -
o_
411
v _ rd-
--
/ ,.,d,„�
50' 25' 0 50' 100' 150'
/ / / / �� // // GRAPHIC SCALE 1" 50' 0" N
US Army Corps
of Engineers,
a
w
0
0
H
m
X
w
Y
0
0
J
0
}
0
w
a
0
w
w
0
LU
a
IL i
GEOGRAPHIC COORDINATE DATA f1 Cq
HORIZONTAL DATUM: a�0R'0pEssi00
li':
NORTH CAROLINA STATE PLANE, NAD83.
VERTICAL DATUM: NAVD88. os9gL ° SHEET ID
'%�/ // /,•"°/ //'"/ // MEASURE:UNITS OF FEET.
xp COORDINATES OWN IN FORMAT OFE•LEPe CG j L
/ EASTING, NORTHING AND ELEVATION.
SOF ANNEX - CIVIL FINAL Calculations, Page 29Pt#,14Ry2T, jf E

�I
Mason&Hanger SOFSTFPhase 3
ADay&Zimmer .Ca a. y Fort Bragg, Hoke County, North Carolina
POSTDEVELOPMENT MAP
Mason & Hanger Page - a.3 -
SOF ANNEX - CIVIL FINAL Calculations, Page 30 of 44 [23 NOV 2021]

11, L 11J� /1 d J 1/1 J, J J�
L-1 -A / l I / / / / /
PUIL\DINP 5 \I�UILDING 5`
a.
�v
/Z�"/ WWI
AP M
-7
A,
2�
A
..........
■ A
ij11 B IL IN I ♦I / .
j T1011t) -41LDING 4-
R 13A
p
14- AnI
7
/*4
BI AREA 816AREA
L3Up f--
�L)ING I I I / /
9V 4
.......... ..................... .......... ................
--B10 AREA
B10 AREA B10 AREA
7 6
............................... ........ .....................
iBUILP.No 7 V
ED
B10 AREA Bib IAREA
9 8
................ 7 1
..............
j
I IUILIING
411 4 B10 AREA B10 AREAsTo
10 J ■
1311 NNN
ID 6
. M3)
t I I I I' I FJ1 t+
................. ...........................................
..........
i
A
nh
�4
r 7i
%
,66
ap
x x x
CONT ACTQR
STAGy9G ARP
4-
W
Al
r
x,`/ 7
CELL
DRAINAGE
AREA
REQUIRED
STORAGE
(NCDEQ)
PROVIDED
STORAGE
(NCDEQ)
1
5.94
10418 CF
11310 CF
2
1.72
3484 CF
3809 CF
556 CF
1912 CF
4
0.38
976 CF
1020 CF
5
0.40
934 CF
1020 CF
6
0.30
694 CF
963 CF
7
0.39
959 CF
963 CF
8
0.30
694 CF
963 CF
9
0.30
694 CF
963 CF
10
0.33
727 CF
1020 CF
11
0.39
947 CF
1020 CF
7,
J-
J-i
�-7
50' 25' 0 50' 100, 150,
GRAPHIC SCALE: 1"=501-01,
GEOGRAPHIC COORDINATE DATA
HORIZONTAL DATUM:
NORTH CAROLINA STATE PLANE, NAD83.
VERTICAL DATUM: NAVD88.
UNITS OF MEASURE: U.S. SURVEY FEET.
COORDINATES SHOWN IN FORMAT OF
FASTING,
,
�NORTHING AND ELEVATION.
US Army Corps
of Engineers'
co
SHEET ID
CG703
SCIF ANNEX - CIVIL FINAL Calculations, Page 31�QY2 if E

�I
Mason&Hanger SOFSTFPhase 3
ADay&Zimmer .Ca a. y Fort Bragg, Hoke County, North Carolina
EISA 438 CALCULATIONS
Mason & Hanger Page - a.4 -
SOF ANNEX - CIVIL FINAL Calculations, Page 32 of 44 [23 NOV 2021]

Army LID
Planning and Cost Tool Report
PROJECT INFO
SITE INFO AND EISA VOLUME
Date 1/3/2019
REQUIREMENT
Army Command IMCOM
Project limit of disturbance (ac) F 5.94
Army Installation Fort Bragg
95% rainfall depth (in) 1.8
Project name SOF Phase 3 Bio
1 Soil type Sandy
Project description
Hydrologic Soil Group (HSG) A
SOF Phase 3 Bioretention Area 1
Pre -project curve number (CN) 30
Post -project curve number (CN) 75
User Name FMM
Pre -project runoff volume (cf) 0
Master Planner
Post -project runoff volume (cf) 6200
EISA Section 438 retention volume 6200
requirement (cf)
LID PLANNING SUMMARY
Structural BMP Surface area
Runoff volume Non-structural BMP
(so
retained (cl
Bioretention: 0
0 Veg. Filter Strip (Slope >2%, Short Grass):
Swale:
0 Veg. Filter Strip (Slope >2%, Tall Grass):
Permeable Pavement:
0 Veg. Filter Strip (Slope <2%, Short Grass):
Rainwater Harvesting:
0 Veg. Filter Strip (Slope <2%, Tall Grass):
Green Roof:
0 Reforestation (Trees - Short Grass):
Infiltration Practice: 13572
16222 Reforestation (Trees - Shrubs and Tall Grass)
Total retention volume provided by BMPs (co: 16222
Project complies with EISA Section 438.
LID COST SUMMARY
Surface
area (ac)
0.00
0.00
0.00
0.00
0.00
0.00
SOF ANNEX - CIVIL FINAL Calculations, Page 33 of 44 [23 NOV 2021]

NI
Mason&Hanger SOFSTFPhase 3
ADay&Zimmer .Camp—y Fort Bragg, Hoke County, North Carolina
STORMWATER CALCULATIONS
Mason & Hanger Page - a.5 -
SOF ANNEX - CIVIL FINAL Calculations, Page 34 of 44 [23 NOV 2021]

WinTR-55 Current Data Description
--- Identification Data ---
User: FMM Date: 10/3/2018
Project: SOF Phase 3 Units: English
SubTitle: Predevelopment BioretentionHydrology Areal Units: Acres
State: North Carolina
County: Hoke NOAA
Filename: Q:\014503 SOF Special Tactics Facility Phase 3\Design\Civil\Stormwater\Pre-Bio Basins.w55
--- Sub -Area Data ---
Name
Description
Reach
Area(ac)
RCN
Tc
------------------------------------------------------------------------------
PRE
BIO
1
Outlet
5.94
55
0.133
PRE
BIO
2
Outlet
1.72
55
0.133
PRE
BIO
3
Outlet
1.01
55
0.133
PRE
BIO
4
Outlet
0.38
55
0.133
PRE
BIO
5
Outlet
0.4
55
0.133
PRE
BIO
6
Outlet
0.3
55
0.133
PRE
BIO
7
Outlet
0.39
55
0.133
PRE
BIO
8
Outlet
0.3
55
0.133
PRE
BIO
9
Outlet
0.3
55
0.133
PRE
BIO
10
Outlet
0.33
55
0.133
Total area: 11.07 (ac)
--- Storm Data --
Rainfall Depth by Rainfall Return Period
2-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr 1-Yr
(in) (in) (in) (in) (in) (in) (in)
--------------------------------------------------------------------------------
3.67 4.71 5.4 6.5 7.3 8.2 3.03
Storm Data Source: User -provided custom storm data
Rainfall Distribution Type: Type III
Dimensionless Unit Hydrograph: <standard>
WinTR-55, Version 1.00.10 Page 1 10/3/2018 3:08:05 PM
SOF ANNEX - CIVIL FINAL Calculations, Page 35 of 44 [23 NOV 2021]

FMM SOF Phase 3
Predevelopment BioretentionHydrology
Hoke NOAA County, North Carolina
Sub -Area Land Use and Curve Number Details
Sub -Area
Hydrologic
Sub -Area
Curve
Identifier
Land Use
Soil
Area
Number
--------------------------------------------------------------------------------
Group
(ac)
PRE
BIO
1 Woods
(good)
B
5.94
55
Total
Area
/ Weighted
Curve
Number
5.94
55
PRE
BIO
2 Woods
(good)
B
1.72
55
Total
Area
/ Weighted
Curve
Number
1.72
55
PRE
BIO
3 Woods
(good)
B
1.01
55
Total
Area
/ Weighted
Curve
Number
1.01
55
PRE
BIO
4 Woods
(good)
B
.38
55
Total
Area
/ Weighted
Curve
Number
.38
55
PRE
BIO
5 Woods
(good)
B
.4
55
Total
Area
/ Weighted
Curve
Number
.4
55
PRE
BIO
6 Woods
(good)
B
.3
55
Total
Area
/ Weighted
Curve
Number
.3
55
PRE
BIO
7 Woods
(good)
B
.39
55
Total
Area
/ Weighted
Curve
Number
.39
55
PRE
BIO
8 Woods
(good)
B
.3
55
Total
Area
/ Weighted
Curve
Number
.3
55
PRE
BIO
9 Woods
(good)
B
.3
55
Total
Area
/ Weighted
Curve
Number
.3
55
PRE
BIO
1OWoods
(good)
B
.33
55
Total
Area
/ Weighted
Curve
Number
.33
55
WinTR-55, Version 1.00.10 Page 1 10/3/2018 3:08:40 PM
SOF ANNEX - CIVIL FINAL Calculations, Page 36 of 44 [23 NOV 2021]

FMM SOF Phase 3
Predevelopment BioretentionHydrology
Hoke NOAA County, North Carolina
Watershed Peak Table
Sub -Area
Peak
Flow by
Rainfall
Return Period
or Reach
2-Yr
5-Yr
10-Yr
25-Yr
50-Yr
100-Yr
1-Yr
Identifier
----------------------------------------------------------------------------------
(cfs)
(cfs)
(cfs)
(cfs)
(cfs)
(cfs)
(cfs)
SUBAREAS
PRE BIO 1
1.34
4.06
6.25
10.17
13.31
17.02
0.43
PRE BIO 2
0.39
1.18
1.
2.95
3.86
4.93
0.13
PRE BIO 3
0.23
0.69
1.06
1.73
2.27
2.90
0.07
PRE BIO 4
0.09
0.26
0.40
0.65
0.85
1.08
.00
PRE BIO 5
0.09
0.28
0.42
0.69
0.90
1.16
.00
PRE BIO 6
0.07
0.21
0.32
0.52
0.67
0.86
.00
PRE BIO 7
0.09
0.27
0.41
0.67
0.88
1.12
.00
PRE BIO 8
0.07
0.21
0.32
0.52
0.67
0.86
.00
PRE BIO 9
0.07
0.21
0.32
0.52
0.67
0.86
.00
PRE BIO 10
0.08
0.23
0.35
.57
0.75
0.95
.00
REACHES
OUTLET 2.50 7.57 11.65 18. 8 24.83 31.75 0.63
PREDEV 1
Q10 = 6.25 CFS
WinTR-55, Version 1.00.10 Page 1 10/3/2018 3:08:24 PM
SOF ANNEX - CIVIL FINAL Calculations, Page 37 of 44 [23 NOV 2021]

�I
Mason&Hanger
ADay&Zimmer .Ca pa y
SOF STF Phase 3
Fort Bragg, Hoke County, North Carolina
NCDEQ BIORETENTION CELL SUPPLEMENT FORMS
Mason & Hanger Page - a.8 -
SOF ANNEX - CIVIL FINAL Calculations, Page 38 of 44 [23 NOV 2021]

Discrete SCS Curve Number Method (NCDEQ Stormwater BMP Manual 3.3.2)
Location: Bioretention Area 1 Date: 1/10/2019
Soil Group: A
Predevelopment BUA
1 1
1 1�
Predevelopment Open Area
•.
•
1 11
Area 5.94 acres
Total 0 cf
Developed BUA
©
1 1
1 1�
Developed Open Area
Area
2.31
acres
Area
100,534
sf
CN
39
S
15.64
is
3.13
in
P
1
in
Q
0.00
in
V
1 0
cf
Area 5.94 acres
Total 10,418 cf
Storage Required 10,418 cf
Surface Area 13,572 sf
Riser 10 in
Storage Provided 11,310 cf
Note: Runnoff depth for CN <= 70 set to 0.00 for 1.0" rainfall event based upon
TR55 Urban Hydrology for Small Watersheds Table 2-1
SOF ANNEX - CIVIL FINAL Calculations, Page 39 of 44 [23 NOV 2021]

SUPPLEMENT-EZ FORM COVER PAGE
Lur;+,,rumn
Please indicate the types, quantities and locations of SCMs that will be used on this project:
Quantity Location(s)
Infiltration System
Project Name:
Bioretention Cell
11
SOF Complex Phase 3
Wet Pond
Stormwater Wetland
Permeable Pavement
Address
Sand Filter
Rainwater Harvesting
Green Roof
Level Spreader -Filter Strip
Disconnected Impervious Surface
City / Town
Treatment Swale
Fort Bragg
Dry Pond
Designer information for this project:
Applicant:
Name and Title:
F Michael Mayer
Company: Fort Bragg DPW
Organization:
Mason & Hanger
Contact:
Lee Ward
Street address:
300 W Vine St Suite 1300
Mailing Address:
Bldg 3-1333 Butner Rd
City, State, Zip:
Lexington, KY 40507
City, State, Zip:
Fort Bragg. NC 28310
Phone number(s):
859-280-3557
Phone number(s):
Email:
[e-mail]
Email:
Designer
Certification Statement:
I certify, under penalty of law: that this Supplement-EZ form and all supporting
information were prepared under my direction or supervision;
- that the information provided in the form is, to the best of my knowledge
and belief, true, accurate, and complete; and
Siqnature of Designer
- that the engineering plans, specifications, operation and maintenance
agreements and other supporting information are consistent with
the information provided here.
I am aware that there are significant penalties for submitting false
information including the possibility of fines and imprisonment for knowing
Seal
Date
violations as well as a report being made to my professional board.
SOF ANNEX - CIVIL FINAL Calculations, Page 40 of 44 [23 NOV 2021]
Cover Page 1 1:31 PM 11/21/2018

BIORETENTION CELL
SOF Complex Phase 3
THE DRAINAGE AREA 1
Drainage area number 1 Break down of BUA in the drainage area (both new and existing):
Total coastal wetlands area (sq ft) sf Parking / driveway (sq ft) 82704 sf
Total surface water area (sq ft)
sf
Sidewalk (sq ft)
3400 sf
Total drainage area (sq ft)
258605 sf
Roof (sq ft)
71967 sf
BUA associated with existing development (sq ft)
sf
Roadway (sq ft)
sf
Proposed new BUA (sq ft)
158071 sf
Other, please specify in the comment box below (sq ft)
sf
Percent BUA of drainage area
1 61 %
JTotal BUA (sq ft)
158071 sf
COMPLIANCE WITH THE APPLICABLE STORMWATER PROGRAM
Stormwater program(s) that apply (please specify):
Design rainfall depth (in)
1.0 in
EISA 438, ARMY LID, FORT BRAGG IDG
Minimum volume required (cu ft)
10418 cf
Design volume of SCM (cu ft)
11310 cf
GENERAL MDC FROM 02H .1050
#1 Is the SCM sized to treat the SW from all surfaces at build -out?
Yes
#7 If applicable, with the SCM be cleaned out after construction?
Yes
#2 Is the SCM located on or near contaminated soils?
No
#8 Does the mainetenance access comply with General MDC (8)?
Yes
#3 What are the side slopes of the SCM (H:V)?
3:1
#9 Does the drainage easement comply with General MDC (9)?
Yes
#3 Does the SCM have retaining walls, gabion walls or other engineered side slopes?
No
#10 If the SCM is on a single family lot, does the plat comply with General MDC (10)?
Yes
#4 Are the inlets, outlets, and receiving stream protected from erosion (10-year storm)?
Yes
#11 Is there an O&M Agreement that complies with General MDC (11)?
Yes
#5 Is there a a bypass for flows in excess of the design flow?
Yes
#12 Is there an O&M Plan that complies with General MDC (12)?
Yes
#6 What is the method for dewatering the SCM for maintenance?
I Other
1#13 Was the SCM designed by an NC licensed professional?
Yes
BIORETENTION CELL MDC FROM 02H .1052
#1 SHWT elevation (fmsl)
428 ft
#6 Percentage of medium to coarse washed sand by volume
85%
#1 Bottom of the bioretention cell (fmsl)
442 ft
#6 Percentage of fines (silt and clay) by volume
10%
#1 Distance from bottom to SHWT (feet)
14 ft
#6 Percentage of organic matter by volume
5%
#2 Surface area of the bioretention cell (square feet)
13572 sf
#6 Type of organic material
Engineered Fill
#2 Design volume of the bioretention cell (cubic feet)
11310 cf
#7 Phosphorus Index (P-Index) of media (unitless)
10
#2 Ponding depth of the design storm (inches)
10 in
#8 Will compaction be avoided during construction?
Yes
#3 Is the bioretention cell used for peak attenuation?
Yes
#9 Will cell be maintained to a one inch/hour standard?
Yes
#3 Depth of peak attenuation over planting surface (in)
in
#10 Describe the planting plan:
#3 Height of peak attenuation outlet above the planting surface (in)
in
Contractor to provide landscape establishment to achieve 100% coverage throughout site in 12 months. Sod is desired
by the user for cell. User requires no hardwood mulch within cell.
#4 Infiltration rate of the in situ soil (inch/hour)
14.4 in/hr
#4 Diameter of the underdrain pipes (if applicable)
in
#4 Does the design include Internal Water Storage (IWS)?
Yes
#11 Depth of mulch, if applicable (inches)
in
#4 if so, elevation of the top of the IWS (fmsl)
444 ft
#11 Type of mulch, if applicable
na
#4 Elevation of the planting surface (fmsl)
447 ft
#12 How many clean out pipes are being installed?
0
#5 Will the cell contain trees and shrubs?
No
#12 Briefly describe the pretreatment that will be used:
#5 Media depth (inches)
30 in
Minimum T sod strip. All outlet headwalls to cell have rip -rap outlet protection per NCDEQ requirements.
ADDITIONAL INFORMATION
Please use this space to provide any additional information about this bioretention cell that you think is relevant to the review:
Underdrain pipes are not required as infiltration rate greater than 2in/hr. However limited underdrains provided for factor of safety. 2.5 feet of open graded aggregate being provided under engineered fill/media depth in order to provide
additional storage volume within cell to meet requirements for EISA 438. This IWS is in addition to IWS within the media mix. Total IWS greater than 48" for all cells. Additionally, behive grated catch basins are provided as first -line overflow,
above required storage volume. Additional storage provided up to emergency overflow, but not for peak attenuation volume. Maximum depth of storage of cell to emergency overflow is 24". Emergency overflow weir designed for 100yr
storm event. Project based entirely within Fort Bragg (US Gov't property). No easements required. User requires no hardwood mulch due to maintenance issues.
Bioretention
SOF ANNEX - CIVIL FINAL Calculations, Page 41 of 44 [23 NOV 2021]
10:28 AM 1/10/2019

�I
Mason&Hanger SOFSTFPhase 3
ADay&Zimmer .Ca a. y Fort Bragg, Hoke County, North Carolina
OUTLET PROTECTION CALCULATIONS
Mason & Hanger Page - a.9 -
SOF ANNEX - CIVIL FINAL Calculations, Page 42 of 44 [23 NOV 2021]

user input Data
Calculated Value
Reference Data
Designed By: FMM Date: 12/9/201E
Checked By: Date:
Company: Mason & Hanger
Project Name: SOF STF Phase 3
Project No.: 145.03
Site Location (City/Town) Aberdeen
Culvert Id. HW2
Total Drainage Area (acres) (see report)
Step I. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe_ If the culwater depth is less
than half the outlet pipe diameter. it is classified minimum tailw°ater condition.
If it is greater than half the pipe diameter, it is classified maxinttun condition_
Pipes thatoutlet onto wide flat areas with no defined channel are assumed
to have a mininnuar tailwater condition unless reliable flood stage elevations
show otherwise.
Outlet pipe diameter, Do (in.) 24
Tailwater depth (in.) 9
Minimum/Maximum tailwater? Min TW (Fig. 8.06a)
Discharge (cfs) 15.51
Velocity (ft./s) 14.78
Step 2. Based on the tailwater conditions determined in step 1. eater Figure
8.06a or Figure 8.06b, and detenume dso riprap size mid minimunn apron length
(L). The d, , size is the median stone size in a wetl-graded nprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape, and the
apron width at the outlet end from the same figure used in Step 2.
Minimum TW
Maximum TW
Figure 8.06a
Figure 8.06b
Riprap d50, (ft.)
0.75
Minimum apron length, La (ft.)
12
Apron width at pipe outlet (ft.)
6
6
Apron shape
TRAP
Apron width at outlet end (ft.)
14
2
Step 4. Determine the m ..—
stone diameter
d_
= 1.5 x cis,
Minimum TW
Maximum TW
Max Stone Diameter, dmax (ft.)
1.125
0
Step 5. Detenxuae the apron duckness:
Apron thickness = 1.5 x dn,.
Minimum TW Maximum TW
Apron Thickness(ft.) 1.6875 0
Step 6. Fit the nprap apron to the site by making it level for the mimmu m
length, 1a, from Figure 8.06a or Figure 8.06b. Extend the apron farther
downstream and along channel banks until stability is assumed. Keep the
apron as straight as possible and align it with the flow of the receiving stream_
Make nay necessary alig®ent bends new the pipe outlet so that the entrance
into the receiving stream is straight_
Some locations may require lining of the entire charnel cross section to assure
stability
It may be necessary to increase the size of riprap where protection of the
channel sidle slopes is necessary (Appendix 6,05). Where overfalls exist at
pipe outlets or Sows are excessive, a plunge pool should be considered, see
page 8.06.8.
SOF ANNEX - CIVIL FINAL Calculations, Page 43 of 44 [23 NOV 2021]

user input Data
Calculated Value
Reference Data
Designed By: FMM Date: 12/9/201E
Checked By: Date:
Company: Mason & Hanger
Project Name: SOF STF Phase 3
Project No.: 145.03
Site Location (City/Town) Aberdeen
Culvert Id. HW5
Total Drainage Area (acres) (see report)
Step I. Determine the tailwater depth from channel characteristics below the
pipe outlet for the design capacity of the pipe_ If the culwater depth is less
than half the outlet pipe diameter. it is classified mmunum tailw°ater condition.
If it is greater than half the pipe diameter, it is classified maximum condition_
Pipes thatoutlet onto wide flat areas with no defined channel are assumed
to have a mininnuar tailwater condition unless reliable flood stage elevations
show otherwise.
Outlet pipe diameter, Do (in.) 15
Tailwater depth (in.) 12
Minimum/Maximum tailwater? Max TW (Fig. 8.06b)
Discharge (cfs) 5.28
Velocity (ft./s) 4.75
Step 2. Based on the tailwater conditions determined in step 1. eater Figure
8.06a or Figure 8.06b, and detenume dso riprap size mid minimum apron length
(L). The d, , size is the median stone size in a wetl-graded nprap apron.
Step 3. Determine apron width at the pipe outlet, the apron shape, and the
apron width at the outlet end from the same figure used in Step 2.
Minimum TW
Maximum TW
Figure 8.06a
Figure 8.06b
Riprap d50, (ft.)
0.5
Minimum apron length, La (ft.)
10
Apron width at pipe outlet (ft.)
3.75
3.75
Apron shape
TRAP
Apron width at outlet end (ft.)
11.25
1.25
Step 4. Determine the m ..— stone diameter
d_ = 1.5 x cis,
Minimum TW Maximum TW
Max Stone Diameter, dmax (ft.) 0.75 0
Step 5. Detenxuae the apron thickness:
Apron thickness = 1.5 x dn,.
Minimum TW Maximum TW
Apron Thickness(ft.) 1.125 0
Step 6. Fit the nprap apron to the site by making it level for the mimmum
length, 1a, from Figure 8.06a or Figure 8.06b. Extend the apron farther
downstream and along channel banks until stability is assured. Keep the
apron as straight as possible and align it with the flow of the receiving stream_
Make nay necessary alig®ent bends new the pipe outlet so that the entrance
into the receiving stream is straight_
Some locations may require lining of the entire channel cross section to assure
stability
It may be necessary to increase the size of riprap where protection of the
channel side slopes is necessary (Appendix 6,05). Where overfalls exist at
pipe outlets or Sows are excessive, a plunge pool should be considered, see
page 8.06.8.
SOF ANNEX - CIVIL FINAL Calculations, Page 44 of 44 [23 NOV 2021]