SW6111102_HISTORICAL FILE_20120126

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW
DOC TYPE
❑ CURRENT PERMIT
❑ APPROVED PLANS
HISTORICAL FILE
p
DOC DATE
aJ4 Z414
YYYYMMDD

Date: 1 /25112
Transmitted To
Brian Lowther
NCDENR
Att: Brian Lowther, Project No. SW6111102
Wetlands and Stormwater Branch
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Tel: [phone]
Transmittal
Report TC010
Project # 5-1757,
Ft Bragg 3rd Brigade Combat Team (Light) Complex, TEMF
Transmittal Number: 0031
Transmitted By
Alyssa Hepker
Walbridge
777 Woodward Avenue, Suite 300
Detroit, MI 48226
Tel: [phone]
Fax: [phone]
Package Transmitted For As Requested Transmitted Via UPS OVeV(1 J9V1
Item # & Item Reference Description
0001 2.00 Drawings NCDENR Response
Remarks
Mr. Lowther -
As requested, included with this transmittal are the hard copies of the additional information you requested regarding Project
No. SW6111102. D cE(715-11RaW9
Please contact me if you need any additional information.
Thank you,
Alyssa Hepker
Engineering Coordinator
Walbridge
JAN 2 6 201Z
DENR - WATER QUALITY
WERMDS AND STOR"WATER WaX4
Cc: Company Name Contact Name Copies Notes Fax Number
Signature
f /-sA Z
igned Date
Printed on: 112512012 Page 1

r
January 6, 2012
Mr. Brian Lowther
Environmental Engineer
Wetlands and Stormwater Branch
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Michael Baker Jr., Inc.
A Unit of Michael Baker Corporation
Airside Business Park
100 Airside Drive
Moon Township, PA 15108
(412)-269-6300
FAX [phone]
Subject: Comment Response
Stormwater Project No. SW6111102
Fort Bragg Tactical Equipment Maintenance
Facility (TEMF) 3rd Brigade
Cumberland County
Dear Mr. Lowther,
In response to your December 2l, 2011, letter requesting additional information for the above referenced
project, Baker has revised the Stormwater Management Permit Application to address these comments.
The following addresses each of your concerns:
1. There is some missing and incorrect information on the provided supplement
forms. The Design rainfall depth is 5.90 for both BMPs but in the calculations it is 1
inch. There is a discrepancy on the supplement compared to the plans on the media
depth for the bioretention cell. Also, a vegetated filler is indicated on the
bioretention supplement but none is provided For the bioretention cell, a filter strip
is not required. Hotivever, for the infiltration trench a filter strip is required Please
revise the supplement forms.
Response: The supplement forms for both the infiltration trench and bioretention cell have been
updated to address the concerns outlined above. The supplement forms are attached.
Properly designed vegetated filters are required from the overflow of all
infiltration systems. However, this requirement may be difficult to meet on sonic sites
due to topographic or space constraints. For sites that have difficulty meeting this
requirement, the options are available in The BMI' Manual (16.3.9. Offline Bypass &
Vegetated Filter Strip) for waiving of the offllne bypass and vegetated filler strip by
permitting the system under the alternative design criteria in NCAC 2H.1008(h). The
system must demonstrate equal or better stormtivaler control and equal or better
protection of waters of the State and not result in an increased potential for nuisance
conditions.
Response: Due to the site constraints, the proposed development and the topographic
conditions, a filter strip is not a viable option. According to the NCDENR BMP Manual, Section
16.3.9, Off]ine Bypass & Vegetated Filter Strip, item No. 3 indicates that it is possible to waive
the Filter Strip requirement if our design can demonstrate that our infiltration trench can store 2.5
times the design storm and infiltrate that volume at half the infiltration rate within 5 days. Please
see attached Calculation Sheets l & 2 indicating that these design criteria have been met.

faker
NCDENR Comment Response
Dec. 5, 201 l
Page 2
3. Please Provide calculations for the water quality volume for the infiltration
trench.
Response: The design calculation has been included in the attached Calculation Sheet 1.
The Simple Method as outlined in the NCDENR BMP manual was used.
4. Please clearly show outlet structure information for the infiltration trench on the
plans. I believe the outlet for the trench is .IBZ but the elevations do not match the
supplement form.
Response: The outlet structure for the infiltration trench is J62 and has been clearly marked
on the attached drawing sheet CEI OO. Furthermore, the elevations in the supplement form have
been updated to reflect the correct elevations of this structure.
If you need any additional information or have further questions or comments, please feel free to contact
me at the (412) 269-61 16 or at dnicklcs@.rnbakcrco1p.com.
Sincerely,
-10
Duncan M. Nickles, P.E.
Senior Civil Engineer

Permit Number:_
(to be provided by D WQ)
�oF v,aT_90
,A�
r
NC©ENR p Y
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
BIORETENTION CELL SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part ill) must be printed, filled out and submitted along with all of the required information.
i. PROJECT INFORMATION I I
Project name Fart Bragg Tactical Equipment Maintenance Facility (TEMF) 3rd Brigade
Contact name Duncan Nickles
Phone number 412-269-6116
Date November 3, 2011
Drainage area number Drainage Area'A'
lL DESIGN INFORMATION
Site Characteristics
Drainage area
195,149 ft'
Impervious area
151,589 ft2
Percent impervious
77.7% %
Design rainfall depth
1.0 inch
Peak Flow Calculations
Is prelpost conlrol of ;he 1-yr, 24-hr peak flow required?
Y (Y or N)
1-yr, 24-hr runoff depth
3.02 in
1-yr, 24-hr intensity
0.13 in/hr
Pre -development 1-yr, 24-hr peak flow
9,443 ft/sec
Post -development 1-yr, 24-hr peak flaw
15.800 ft3lsec
PTe/Post 1-yr, 24-hr peak control
6.357 ft/sec
Storage Volume: Non -SA Waters
Minimum volume required
4,390.0 fill
Volume provided
4,420.0 ft'
OK
Storage Volume: SA Waters
1.5" runoff volume
ft3
Pre -development 1-yr, 24-hr runoff
ft3
Post -development 1-yr, 24-hr runoff
ft3
Minimum volume required
0 ft3
Volume provided
ft3
Cell Dimensions
Ponding depth of water
12 inches
OK
Ponding depth of water
1.00 ft
Surface area of the top of the bioretention cell
4,420.0 ft2
OK
Length:
68 ft
OK
Wrdth:
65 ft
OK
-or- Radius
ft
Media and Soils Summary
Drawdown time, ponded volume
12 hr
OK
Drawdown time, to 24 inches below surface
24 hr
OK
Drawdown time, total:
36 hr
In -situ soil:
Soil permeability
0.00 inthr
Insufficient. increase infiltration rate or include underdrains.
Planting media snit:
Soil permeability
1.50 infhr
OK
Soil composition
% Sand (by volume)
87%
OK
% Fines (by volume)
9%
OK
Form SW401-Bioretention-Rev.13
June 25, 2010
Parts 1 and II. Design Summary, Page 1 of 3

Permit Number:
(to be provided by DWQ)
% Organic (by volume) 4% OK
Total: 100%
Phosphorus Index (P-Index) of media
(unitless)
Form SW401-Bioretention-Rev.8
June 25, 2010 Paris I and II. Design Summary, Page 2 of 3

Permit Number —
(to be provided by DWQ)
Basin Elevations
Temporary pool elevation 284.80 fmsl
Type of bioretention cell (answer "Y" to only one of the two following
questions):
Is this a grassed cell? Y (Y or N) OK
Is this a cell with trees/shrubs? N (Y or N)
Planting elevation (top of the mulch or grass sod layer) 283.8 fmsl
Depth of mulch 24 inches Insufficient mulch depth, unless installing grassed cell.
Bottom of the planting media soil 281.8 fmsl
Planting media depth 2 ft
Depth of washed sand below planting media soil 0.33 ft
Are underdrains being installed?
Y
(Y or N)
How many clean out pipes are being installed?
5
OK
What factor of safety is used for sizing the underdrains? (See
2
OK
BMP Manual Section 12.3.6)
Additional distance between the bottom of the planting media and
1 tt
the bottom of the cell to account for underdrains
Bottom of the cell required
280.47 fmsl
SHWT elevation
264 fmsl
Distance from bottom to SHWT
16.47 fi
OK
Internal Water Storage Zone (IWS)
Does the design include IWS
Y
(Y or N)
Elevation of the top of the upturned elbow
281.3 fmsl
Separation of IWS and Surface
2.5 ft
OK
Planting Plan
Number of tree species
0
Number of shrub species
0
Number of herbaceous groundeover species
0
Recommend more species.
Additional Information
Does volume in excess of the design volume bypass the
Y
(Y or N)
OK
bioretention cell?
Does volume in excess of the design volume flow evenly distributed
N
(Y or N)
Excess volume must pass through filler.
through a vegetated filter?
What is the length of the vegetated filter?
0 ft
Does the design use a level spreader to evenly distribute flow?
N
(Y or N)
Show how flow is evenly distributed.
is the BMP located at least 30 feet from surface waters (50 feet if
SA waters)?
Y
(Y or N)
OK
Is the BMP located at least 100 feet from water supply wells?
Y
(Y or N)
OK
Are the vegetated side slopes equal to or less than 3:1?
Y
(Y or N)
OK
Is the BMP located in a proposed drainage easement with access
Y
(Y or N)
OK
to a public Right of Way (ROW)?
Inlet velocity (from treatment system)
1 ft/sec
OK
is the area surrounding the cell likely to undergo development in the
N
(Y or N)
OK
future?
Are the slopes draining to the bioretention cell greater than 20%?
N
(Y or N)
OK
Is the drainage area permanently stabilized?
Y
(Y or N)
OK
Pretreatment Used
(Indicate Type Used with an'X" in the shaded cell)
Gravel and grass
($inches gravel followed by 3-5 ft of grass)
X
Grassed swale
OK
Forebay
Other
Form SVV401-8iorelenlion-Rev.9
June 25. 2010 Parts I and 11. Design Summary, Page 3 of 3

Permit No.
(to be provided by DWQ)
6V A r4.fi
NC©ENR STORMWATER MANAGEMENT PERMIT APPLICATION FORM a
401 CERTIFICATION APPLICATION FORM
INFILTRATION TRENCH SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part /A) most be printed, filled out and submitted along with all of the required information.
I. PROJECT INFORMATION
Project name Forl Bragg Tactical Equpment Maintenance Facility (TEMF) 3rd Brigade
Contact person Duncan Nickles
Phone number 412-269-6116
Date 1102011
Drainage area number Drainage Area'B'
II. DESIGN INFORMATION
Site Characteristics
Drainage area
517,928.00
ft'
Impervious area
455,659.00
fe
Percent impervious
8H%
%
Design rainfall depth
1.00
in
Peak Flow Calculations
1-yr, 24-hr rainfall depth
1-yr, 24-hr intensity
Pre -development 1-yr, 24-hr discharge
Post -development 1-yr, 24-hrdischarge
Pre/Post 1-yr, 24-hr peak flow control
Storage Volume: Non -SA Waters
Minimum volume required
Volume provided
Storage Volume: SA Waters
1.5" runoff volume
Pre -development 1-yr, 24-hr runoff volume
Post -development 1-yr, 24-hr runoff volume
Minimum volume required
Volume provided
Soils Report Summary
Soil type
Infiltration rate
SHWT elevation
Trench Design Parameters
Drawdown time
Perforated pipe diameter
Perforated pipo length
Number of laterals
Stone type (if used)
Stone void ratio
Stone is free of Fines?
3.uz in
0.13 inthr
8.43 ft'lsec
40.37 ft'lsec
31,94 ft'Isec
66,900.00 ft3
96,840.00 ft3 Oft for non -SR waters
ff3
ft3
ff3
ff3
ff3
Sand,A
1.42 Whr
264,00 fmsl
4.06 days CK
96.00 in
1,400.00 tt
4
AASHTO #57
40%
Y (Y or N) OK
Form SW401-infiltration Trench-Rev.4 Parts I. & It. Design Summary, Page 1 of 2

Trench Elevations
Bottom elevation
Storage/overflow elevation
Top elevation
Trench Dimensions
Length (tong dimension)
Width (short dimension)
Height (depth)
Additional Information
Maximum volume to each inlet into the trench?
Length of vegetative filter for overflow
Number of observation wells
Distance to structure
Distance from surface waters
Distance from water supply well(s)
Separation from impervious sal layer
Depth of naturally occuring soil above SHWi
Bottom covered with 4-in of clean sand?
Proposed drainage easement provided?
Capures all runoff at ultimate build -out?
Bypass provided for larger storms?
Trench wrapped with geotextile fabric?
Pretreatment device provided
Permit No.
270.47 frost OK
279,50 frost
280A7 fmsl
1,400.00 ft
12.00 ft
8.00 ft OK
0.50
ac-in
OK
0.00
ft
Filter is too shod, must be > 30-ft
3
OK
NIA
ft
OK
3,300.00
ft
OK
NIA
ft
OK
2.00
ft
OK
18.00
ft
OK
Y
(Y or N)
OK
NIA
(Y or N)
OK,
Y
(Y or N)
OK
Y
(Y or N)
OK
Y
(Y or N)
OK
Baffles at inlets
(to be provided by DWQ)
Form SW401-I0filtration Trench-Rev.4 Parts I. & II, Design Summary, Page 2 of 2

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NCDENR
North Carolina Department of Environment and Natural Resources
Beverly Eaves Perdue
Governor
Mr. Duncan Nickles
Michael Baker Jr. Inc.
100 Airside Drive
Moon Township, PA 15108
Dear Mr. Nickles:
Division of Water Quality
Coleen H. Sullins
Director
December 21, 2011
Dee Freeman
Secretary
Subject: Request for Additional Information
Stormwater Project No. SW6111102
Fort Bragg Tactical Equipment Maintenance
Facility (TEMF) 3rd Brigade
Cumberland County
The Division of Water Quality Central Office received a Stormwater Management Permit Application for
the subject project on December 14, 2011. A preliminary review of that information has determined that
the application is not complete. The following information is needed to continue the stormwater review:
l . There is some missing and incorrect information on the provided supplement forms. The
Design rainfall depth is 5.40 for both BMPs but in the calculations it is 1 inch. There is a
discrepancy on the supplement compared to the plans on the media depth for the bioretention
cell. Also, a vegetated filter is indicated on the bioretention supplement but none is provided.
For the bioretention cell, a filter strip is not required. However, for the infiltration trench a
filter strip is required. Please revise the supplement forms.
2. Properly designed vegetated filters are required from the overflow of all infiltration
systems. However, this requirement may be difficult to meet on some sites due to topographic
or space constraints. For sites that have difficulty meeting this requirement, the options are
available in The BMP Manual (16.3.9. Offline Bypass & Vegetated Filter Strip) for waiving of
the offline bypass and vegetated filter strip by permitting the system under the alternative
design criteria in NCAC 2H .1008(h). The system must demonstrate equal or better stormwater
control and equal or better protection of waters of the State and not result in an increased
potential for nuisance conditions.
3. Please provide calculations for the water quality volume for the infiltration trench.
4. Please clearly show outlet structure information for the infiltration trench on the plans. I
believe the outlet for the trench is JB2 but the elevations do not match the supplement form.
Please note that this request for additional information is in response to a preliminary review. The
requested information should be received by this Office prior to January 9, 2012, or the application) will
be returned as incomplete. The return of a project will necessitate resubmittal of all required items,
including the application fee.
Wetlands and Stormwater Branch
1617 Mail Service Center, Raleigh, North Carolina 27699-1617
Location 512 N. Salisbury St. Raleigh, North Carolina 27604
Phone: [phone] FAX: 91M07-64941 Customer Service: 1-877-623-6748
Internet: www,ncwaterquality.org
An Fni iii nrnnrinnily % Arfirmafivn Arainn Fmnlnvpr
Noce hCarolina
;atural!
U

SW6091 l 102
If you need additional time to submit the information, please mail or fax your request for a time extension
to the Division at the address and fax number at the bottom of this letter. The request must indicate the
date by which you expect to submit the required information. The Division is allowed 90 days from the
receipt of a completed application to issue the permit.
Please reference the State assigned project number on all correspondence. If you have any questions
concerning this matter please feel free to call me at [phone].
Sincerely,
Brian Lowther
Environmental Engineer
cc: Fayetteville Regional Office
SW6111102 File
David Heins, Environmental Division Chief, DPW

M
December 05, 2011
Mr. Brian Lowther
Environmental Engineer
Wetlands and Stormwater Branch
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Michael Baker Jr., Inc.
A Unit of Miehae! Baker Corporation
Airside Business Park
100 Airside Drive
Moon Township, PA 15108
(412)-269-6300
FAX [phone]
Subject: Comment Response
Stormwater Project No. SW6111102
Fort Bragg Tactical Equipment Maintenance
Facility (TEMF) P Brigade
Cumberland County
Dear Mr. Lowther,
In response to your November 30, 2011, letter requesting additional infonnation for the above referenced
project, Baker has revised the Stormwater Management Permit Application to address these comments.
The following addresses each of your concern:
Please make sure the calculations are signed, sealed, and dated.
Response: All calculations have been signed, sealed and dated. All referenced calculations can be
found in Appendix C, titled "Stormwater Management Plan Drawings, Calculations, and
Specifications."
2. Please include delineated drainage areas on the main plan sheets for each BMP.
Response: The drainage areas have been identified on the main plan sheet for each BMP. Please
see drawing CE 100 in Appendix C, titled "Stormwater Management Plan Drawings, Calculations,
and Specifications."
3. The checklists for each supplement were not included. This item is III. Required Items
Checklist of the form and is a tab on the excel document. Please include both checklists
with resubmillal.
Response: The Checklists for each supplement have been included with the supplement forms in
Appendix D, "Stormwater Pen -nit Application and Forms."
4. More detail is needed for the Bioretention cell. Please .show underdrains as well as the
overflow/outlet in the plan view. Please spec fy the type of sod for the cell.
Response: A more through detail, including the underdrains and the overflow design, has been
added to the Bioretention cell plan and profiles sheet, C-507, Bioretention Design Detail. Also,
the underdrain design calculations, per the North Carolina Department of Environment and
Natural Resources (NCDENR) BMP Design Manual, have been included in the calculations
section in Appendix C.
More detail is needed fc)r the infiltration trench to completely understand the system and

NCDENR Comment Response
Dec. 5, 2011
Page 2
where it is located, Please clearly show which sections are perforated and are included
in the water quality treatment calculations. The application and supplement indicate the
infiltration trench is treating drainage area B but there are also is an underground
stormwater management system in drainage area A. It may be necessary to submit
multiple supplement forms for each infiltration trench in order to understand the system.
The requested delineated drainage areas may also resolve this issue.
Response: The narrative and drawings have been updated to more clearly identify the location of
the BMPs and the drainage area that each will treat. The perforated infiltration trench is only used
to treat Drainage Area B for the water quality requirements set forth by the NCDENR DWQ BMP
Manual. The underground stormwater management system in Drainage Area A is only to control
the rate and volume for this respective drainage area. The Bioretention cell will be used as the
BMP to treat the water quality requirements of Drainage Area A. There is a baffle system in the
junction box for each underground stormwater management facility to allow the first 1.0 inch of
rainfall to be treated by each respective BMP and store the excess volume to control to pre -
development conditions for rate and volume. Once again, the narrative has been revised to better
explain this situation.
6. The narrative refers to a sand filter multiple times. A sand filler is different BMP than the
ones proposed and the references are confusing. Please correct the references.
Response: We understand that a sand filter is different than a Bioretention facility; at one point, a
sand filter was proposed in lieu of the Bioretention facility but it was revised based on comments
from the Fort Bragg staff. All of the references to the sand filter have been removed and the
narrative has been revised to refer to the Bioretention facility. 1
If you need any additional infortnation or have further questions or comments, please feel free to contact
me at the (412) 269-61 16 or at dnick lesg.jnbakercorp.com.
Sincerely,
Duncan M. Nickles, P.E.
Senior Civil Engineer

North Carolina
Beverly Eaves Perdue
Governor
Mr. Duncan Nickles
Michael Baker Jr. Inc.
100 Airside Drive
Moon 'Township, PA 15108
Dear Mr. Nickles:
A
NC®ENR
Department of Environment and Natural Resources
Division of Water Quality
Coleen H. Sullins
Director
November 30, 2011
Subject: Request for Additional Information
Dee Freeman
Secretary
Stormwater Project No. SW6111102
Fort Bragg Tactical Equipment Maintenance
Facility (TEMF) 3rd Brigade
Cumberland County
The Division of Water Quality Central Office received a Stormwater Management Permit Application for
the subject project on November 14, 2011. A preliminary review of that information has determined that
the application is not complete. The following information is needed to continue the stormwater review:
1. Please make sure the calculations are signed, sealed, and dated.
2. Please include delineated drainage areas on the main plan sheets for each BMP.
3. The checklists for each supplement were not included. This item is 111. Required Items
Checklist of the form and is a tab on the excel document. Please include both checklist with
resubmittal.
4. More detail is needed for the Bioretention cell. Please show underdrains as well as the
overflow/outlet in the plan view. Please specify the type of sod for the cell.
5. More detail is needed for the infiltration trench to completely understand the system and where
it is located. Please clearly show which sections are perforated and are included in the water
quality treatment calculations. The application and supplement indicate the infiltration trench
is treating drainage area B but there also is an underground stormwater management system in
drainage area A. It may be necessary to submit multiple supplement forms for each infiltration
trench in order to understand the system. The requested delineated drainage areas may also
resolve this issue.
6. The narrative refers to a sand filter multiple times. A sand filter is different BMP than the
ones -proposed and the references are confusing. Please correct the references.
Please note that this request for additional information is in response to a preliminary review. The
requested information should be received by this Office prior to December 16, 2011, or the application
will be returned as incomplete. The return of a project will necessitate resubmittal of all required items,
including the application fee.
Wetlands and Stormwater Branch
1617 Mail Service Center, Ralegh, North Carolina 27699-1617
Location: 512 N. Salisbury St. Raleigh, North Carolina 27604
Phone: [phone] FAX: [phone] Customer Service: 1-877-623-6748
Internet: www.ncwaterquality.org
.One Carolina
aturallry
An Fnual Onnnrtnnily I Affrmaliva An6nn FmnlnVAr

SW60911102
If you need additional time to summit the information, please mail or fax your request for a time extension
to the Division at the address and fax number at the bottom of this letter. The request must indicate the
date by which you expect to submit the required information. The Division is allowed 90 days from the
receipt of a completed application to issue the permit.
Please reference the State assigned project number on all correspondence. If you have any questions
concerning this matter please feel free to call me at [phone].
Sincerely,
Brian Lowther
Environmental Engineer
CC" Fayetteville Regional Office
SW6111102 File
David Heins, Environmental Division Chief, DPW

TRANSMITTAL'OF SHOP DRAWINGS, EQUIPMENT DATA, MATERIAL SAMPLES, OR
DATE
TRANSMITTAL NO.
MANUFACTURER'S CERTIFICATES OF COMPLIANCE
12/13/2011
01 57 20.00 10-3
(Read instructions on the reverse side prior to initiating this form)
SECTION I - REQUEST
FOR APPROVAL OF THE FOLLOWING ITEMS (This section will be initiated by the contractor)
TO: Fort Bragg Area Office
FROM: Walbridge A Company
CONTRACT NO.
CHECK ONE:
Bldg 3-1933 Butner Road/POB 70247
Avr
© THIS IS A NEW TRANSMITTAL
Fort Bragg, INC 28310
rd
777 Woodward Ave 5TE 300
W912HN-09 D 0023 0002
❑ THIS IS A RESUBMITTAL OF
Detroit, MI 48226-1365
TRANSMITTAL
SPECIFICATION SEC. NO. (Cover only one section with each
PROJECT TITLE AND LOCATION 01-Main Register
CHECK ONE: THIS TRANSMITTAL IS
transmittal) 01 57 20,00 10
1 TO#02-TEMF 31D BCT Cpx 64342
FOR ❑Flo ®GA ❑ DA ❑ CR
ITEM
DESCRIPTION OF ITEM SUBMITTED
MFG OR CONTR.
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PARA. NO.
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Revised Stormwater Management Report
TEST REPORTS
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I certify that the above submitted items have been reviewed
in detail and are correct and in the strict conformance with the
contract drawings and specifications except as otherwise
stated.
Ua 6LO naf\k mtum
NAME AND SIGNATURE OF CONTRACTOR
SECTION
II - APPROVAL ACTION
ENCLOSURES RETURNED (List by item No.)
NAME, TITLE AND SIGNATURE OF APPROVING AUTHORITY
DATE
ENG FORM 4025, MAR 95 (ER 415-1-10) EDITION OF SEP 93 IS OBSOLETE. SHEET 1 OF 1 (Proponent: CEMP-CE)

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TRANSMITTAL OF SHOP DRAWINGS, EQUIPMENT DATA, MATERIAL SAMPLES, OR
MANUFACTURER'S CERTIFICATES OF COMPLIANCE
(Read instructions on the reverse side prior to initiating this farm)
DATE
12/13/2011
TRANSMITTAL NO.
01 57 20.00 10-3
SECTION I - REQUEST
FOR APPROVAL OF THE FOLLOWING ITEMS (This section will be initiated by the contractor)
TO: Fort Bragg Area Office
Bldg 3-1933 Butner Road/POB 70247
Fort Bragg, NC 28310
FROM:
Walbridge Aldinger Company
777 Woodward Ave STE 300
Detroit, MI 48226-1365
CONTRACT NO.
W912HN-09-D 0023 0002
CHECK ONE:
THIS IS A NEW TRANSMITTAL
THIS IS A RESUBMITTAL OF
TRANSMITTAL
SPECIFICATION SEC. NO. (Cover only one section with each
transmittal) 01 57 20.00 10
PROJECT TITLE AND LOCATION 01-Main Register
1 TO#02-TEMF 3D BCT Cpx64342
CHECK ONE: THIS TRANSMITTAL IS
FOR ❑FIO ®GA ❑DA ❑CR
ITEM
NO.
a.
DESCRIPTION OF ITEM SUBMITTED
(Type size, model number/etc.)
b.
MFG OR CONTR.
CAT., CURVE
DRAWING OR
BROCHURE NO.
(See instruction no. 8)
C.
NO,
OF
COPIES
d.
CONTRACT REFERENCE
DOCUMENT
FOR
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USE CODE
g.
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No. 6)
h.
FOR
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USE
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PARA. NO.
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f.
2.1
Revised Stormwater Management Report
TEST REPORTS
2
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REMARKS UU
D E C 1 4 2011
DERR -WATER QUALITY
WETLAND$ AND STORMWATER BRMCH
I certify that the above submitted items have been reviewed
in detail and are correct and in the strict conformance with the
contract drawings and specifications except as otherwise
stated.
/
{/ �YII� 1 i 11C:Jr�21L
NAME AND SIGNATURE OF CONTRACTOR
SECTION
II - APPROVAL ACTION
ENCLOSURES RETURNED (List by item No.)
NAME, TITLE AND SIGNATURE OF APPROVING AUTHORITY
DATE
ENG FORM 4025, MAR 95 (ER 415-1-10) EDITION OF SEP 93 IS OBSOLETE. SHEET 1 OF 1 (Proponent CEMP-CE)

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Certif!edbyQCM=W. 1-LLzz))i.
Walbnidge

STORM WATER
MANAGEMENT REPORT
FOR
US ARMY CORP OF ENGINEERS
TACTICAL EQUIPMENT MAINTENANCE FACILITY
(TEMF)
3RD BRIGADE COMBAT TEAM (BCT) COMPLEX
FORT BRAGG, NC
(REVISED) DECEMBER, 2011
Prepared By
,r
Michael Baker Jr. Inc.
Moon Township, Pa

®a•p•a�.a a
STORM WATER
MANAGEMENT REPORT
MAN
US ARMY CORP OF ENGINEERS
TACTICAL EQUIPMENT MAINTENANCE FACILITY
(TEMF)
3RD BRIGADE COMBAT TEAM (BCT) COMPLEX
FORT BRAGG, NC
(REVISED) DECEMBER, 2011
01
V2
1 4 2011
4AN,S1% "".ATE VMCH
Prepared By
Michael Balser Jr. Inc.
Moon Township, Pa

® US Army p g Corps of Engineers
Tactical Equipment Maintenance Facility (TEMF)
3rd Brigade Combat Team (BCT) Complex
Fort Bragg, North Carolina
Stormwater Management Plan
(Revised) December 2011
Table of Contents
Section
Paee No.
Tableof Contents...................................................................................................... i
Appendices................................................................................................................. ii
List of Abbreviations................................................................................................. ii
1.0
Introduction........................................................................................................1
2.0
Site Location and Characteristics...................................................................... I
FigureI -- Location Map.............................................................................. 2
3.0
Design Basis and Assumptions...........................................................................3
3.1 Site Soils.......................................................................................................3
Table 3.1 -- Site Soils Information.................................................................4
3.2 Assumptions..................................................................................................4
4.0
Pre -developed Conditions and Results..............................................................
5
5.0
Post -developed Conditions and Results.............................................................6
5.1 Storm Sewer Design......................................................................................
6
6.0
Stormwater Management Faci6tes and Routings.............................................7
Table 6.A -- Summary of Sub-areas...............................................................
7
Table 6.13 -- Summary ol' Storm Routings to POI ..........................................
8
6.1 Water Quality................................................................................................
8
7.0
Environmental Impacts, Permitting, and Maintenance....................................9
7.1 Wetlands and Permitting ..................................
.......... 9
7.2 NPDES Permit..............................................................................................9
7.3 Stormwater 13MPs - Operation and Maintenance ...........................................
9
7.3.1 Inspection/Maintenance Frccluency............................I..................9
•

0
US Army Corps of Engineers
Tactical Equipment Maintenance Facility (TEMF)
3rd Brigade Combat Team (BCT) Complex
Fort Bragg, North Carolina
Stormwater Management Plan
(Revised) December 2011
Appendices
Appendix A: Vicinity Map
Appendix B: Site Soils and Geotechnical Report
Appendix C: Stormwater Management Plan Drawings, Calculations, and Specifications
Appendix D: Stormwater Permit Application and Forms
121233
Michael Baker Jr., Inc.
Page ii

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US Army Corps of Engineers; Tactical Equipment Maintenance Facility
Stormwater Management Plan (Revised) December 2011
1.0 Introduction
The purpose of this project is to construct the Tactical Equipment Maintenance Facility
(TEMF) located in the cantonment area of Fort Bragg. The facility will be spread over two
blocks bounded by Butner Road, Keerans Street, Taylor Street, and Gruber Road. This
TEMF project will include the construction of a TEMF building, six Organizational Storage
Buildings (OSBs), an Unmanned Aerial Vehicle (UAV) storage building, oil storage, open
storage, HAZMAT storage, and organizational vehicle parking. The project also includes the
widening of Spooner Street, the addition of turning lanes, additional sidewalk s along Butner
Road adjacent to the intersections with Keerans Street and Spooner Street and the addition of
a Privately Owned Vehicle (POV) lot adjacent to Spooner Street. These facilities will be
constructed around existing in -use facilities.
This project will be delivered to the Government utilizing the Design -Build procedure. The
project will be constructed in several phases so that design and construction activities occur
concurrently. These phases include site demolition, early utilities/grading/foundations and
building construction.
The final product will include all site work, infrastructure improvements, utility improvements,
landscaping and permanent stormwater management facilities. The existing site is currently
developed with over 70% impervious area comprised of concrete hardstand, existing
0 buildings, and parking areas. The development site is approximately 16 acres. Please see the
Vicinity Map, Figure 1 for the site location.
This Stormwater Management Plan will be prepared to provide stormwater management
controls as required by Fort Bragg and the NCDENR.
2.0 Site Location and Characteristics
The development site's existing conditions consist of multiple buildings, paved areas and
concrete hardstand. There are some trees which will be removed by Fort Bragg prior to the
start of construction and some areas are sparsely vegetated with grass. The site slopes
generally from the south to the north at approximately a 2 percent slope. Around the parking
areas there are some steep sloped embankments differentiating the various areas of the site
between parking and roads.
The facility will be spread over two blocks bounded by Butner Road, Keerans Street, Taylor
Street, and Gruber Road. Spooner Street bisects the site area and as part of this project it is
proposed to be widened between Butner Road and Kero Street. Several existing storm sewer
facilities are in the proximity of the development site. Due to the grade of the development
two separate points of connection to the existing storm sewer system have been identified and
will be utilized as the discharge points for the stormwater runoff from the development site.
9
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US Army Corps of Engineers; Tactical Equipment Maintenance Facility
Stormwater Management Plan (Revised) December 2011
The two separate areas that drain to these two discharge points will be treated as spate
drainage areas and control the stormwater runoff individually. For the purpose of this report
these two areas have been identified as Area A and Area B. The storm sewer runoff from
Area A along Gruber Road between Butner Road and Taylor Street will discharge into the 24
inch storm sewer culvert at the intersection of Butner and Gruber Roads. The stormwater
runoff from the development along Spooner Street between Butner Road and Taylor Street
and along Butner Road will discharge into the existing 48 inch storm sewer culvert along
Butner Road. Area A and B can be seen on the attached site drawing in Appendix F.
Stormwater runoff from the site flows into an unnamed tributary to Beaver Creek. Beaver
Creek has been assigned a Class C (fishable/swimmable) rating by the NCDENR Department
of Water Quality (DWQ). This is the minimum standard that all North Carolina waters must
meet. The entire project area is within the Cape Fear River basin. Wetlands do not exist on the
site, and the river basin has no riparian buffer requirements.
Figure 1 -- Location Map
APPROXIMATE SCALE: NTS
SOURCE: Google daps — Aerial view
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US Army Corps of Engineers; Tactical Equipment Maintenance Facility
Stormwater Management Plan (Revised) December 2011
3.0 Design Basis and Assumptions
In order to model both the existing and proposed site conditions, as well as to estimate the
approximate amount of storage that will be required by the development, the following design
methods were used:
• SCS and TR 55 computer programs, as implemented by Hydraflow
Hydrographs, used for storage estimation, storm routing and hydrograph
development.
• NCDENR Stormwater BMP Manual, used to determine water quality
volume for non -coastal counties. Control and treat the first 1.0 inches of
rain, NCDENR recommends treating the first 1.0 — 1.5 inches of rain,
however the RFP stated for this project to treat the first 1.0 inches of rain.
The computer programs listed above require input data consisting of several different
constants and variables. In order to obtain all of the information required by the programs,
certain assumptions were made concerning both existing and proposed site conditions. This
section discusses the input data and the assumptions used.
3.1 Site Soils
Site soil information was obtained from the following web site:
http://websoilsurvey.nrcS.usda.gov (see Appendix D). The soils located on the site, in the
upstream drainage area, and on the adjacent properties, are listed in Table 3.1. Site soil
limitations were taken from the above web site (see Appendix D for descriptions of soil
limitations). A preliminary Geotechnical Report entitled "Subsurface Exploration Report
(Preliminary), by Soils Section, Geotechnical & HTRW Branch, U.S. Army Engineer District,
Savannah also confirms the soils present are of sands and would possess such hydrologic
classification as outlined in the Table below. The preliminary geotechnical investigation is
also included in Appendix D. However upon further investigation during the final
geotechnical report it was determined that there are areas of localized impermeable clayey
sands that would not be classified under the soils group classification identified in the above
referenced United States Geological Survey (USGS) data. A final detailed geotechnical
investigation was performed by ECS Carolinas, LLP for the project site.
Site soils are Group A soils. A detailed description of the soil follows:
• Group A soils have a high infiltration rate (low runoff potential) when thoroughly wet
and consist mainly of deep, well drained to excessively drained sands or gravelly sands.
124436 Michael Baker Jr., Inc.
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US Army Corps of Engineers; Tactical Equipment Maintenance Facility
Stormwater Management Plan (Revised) December 2011
These soils have a high rate of water transmission. However, at this particular site
there are areas of localized impermeable clayey sands.
Table 3.1 -- Site Soils Information
Hydrologic
Map Unit Map Unit Name - Description
Slope
Classification
Symbol
WgB Wagram-Urban Land Complex, 0 to 8 percent
0% to 8%
L
A
I
slopes
As the majority of the soils on the site arc as described above, the soils present within
the drainage Area A contain very stiff to hard clayey sands and the infiltration rate does
not apply to this area. A permeability test was performed and the soils found on Area
A tested to have an infiltration rate of 0.00022 in/hr. The soils found in Area B have an
infiltration rate of 1.42 in/hr and categorized as a medium dense silty sand. Data show
in Appendix D.
3.2 Assumptions
Several assumptions were incorporated in order to model the existing and proposed site
conditions. The following is a Summary of the assumptions used:
• The 1DF curves were created for the region by using rainfall data as indicated in
the RFP for the various storm events used to analyze the site.
• Pre -Developed Runoff. The following information was utilized to determine
the pre -developed runoff for the watershed area:
♦ Topography and site information has been taken from site survey
performed by McKim & Creed.
♦ Developed areas within the watershed were considered to be 100%
impervious. The runoff curve value that was utilized for these areas is 98
regardless of the underlying hydrologic soil classification.
Undisturbed areas that are not developed utilized a runoff curve value of
70. This value was taken from the NCDENR Stormwater BMP Manual
for soils of hydrologic soil group A.
♦ Time of concentration and travel times for the various tributaries in the
watershed were estimated based on the flows generated by the 2-year 24-
hour storm. A time of concentration (Tc) of 6 minutes was calculatcd for
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US Army Corps of Engineers; Tactical Equipment Maintenance Facility
Stormwater Management Plan (Revised) December 2011
Pre -Developed Area A. A Tc of 14 minutes was calculated for Pre -
Developed Area B.
• Post -Developed Runoff: The following information was utilized to determine
the post -developed runoff for the watershed area:
• All buildings, parking areas and paved surfaces have been constructed.
♦ Areas of proposed development have a runoff curve value of 98 regardless
of the underlying hydrologic soil classification. The Developed Areas
were conservatively drawn on the watershed map.
♦ All post -developed subareas time of concentration and travel times for the
various tributaries in the watershed were estimated based on the flows
generated by the 2-year 24-hour storm.
♦ A Tc of 5.0 minutes was calculated for Post -Developed Area A. A Te of
6.8 minutes was calculated for Post -Developed Area B.
Any other assumptions used for the design of the Stormwater management plan are discussed
in the specific areas of the report where they apply.
4.0 Pre -developed Conditions and Results
Pre -developed runoff is based on the previously listed information and assumptions, and on
the areas and conditions determined from the base mapping before construction of the TEMF
project. The pre -development conditions for the analysis were calculated for the rate and
volume of discharge as if the site was completely undeveloped natural forest land as indicated
in the RFP.
The development site is divided into two subareas, A and B. Subarea A is located along
Gruber Road between Taylor Street and Butner Road. It is comprised of 4.48 acres. Subarea
B is the remainder of the development site and includes the areas surrounding Spooner Street,
Weritch Street between Taylor Street and Butner Road and Prager Street between Spooner
Street and Kerrans Street. It is comprised of 11.89 acres. Subarea A has no stormwater
management facilities and currently sheet flows off site to the adjacent roadways. Subarea B
currently consists of roughly 75% of pervious area and does not have any stormwater
management facilities. Water is collected in gutters that run along the side of the road and site
sheet flows in a northwesterly direction towards the intersection of Butner Road and Gorham
Street. Therefore, the site will be considered as two different watersheds, draining in two
different directions.
124436 Michael Baker Jr., Inc.
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9
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US Army Corps of Engineers; Tactical Equipment Maintenance Facility
Stormwater Management Plan (Revised) December 2011
Stormwater runoff from the site flows into the Ft. Bragg stormwater collection system and
eventually through an unnamed tributary to Beaver Creek. Beaver Creek has been assigned a
Class C (fishable/swimmable) rating by the NCDENR Department of Water Quality (DWQ).
This is the minimum standard that all North Carolina waters must meet. The entire project
area is within the Cape Fear River basin. Wetlands do not exist on the site, and the river basin
has no riparian buffer requirements.
5.0 Post -developed Conditions and Results
The objective of this Stormwater management plan is to reduce the built upon area such that
the post -development rate is less than the prc-development runoff rate, while providing the
required stormwater treatment in the underground infiltration facilities and bio-retention area
to meet the water quality standards set forth in the NCDENR Stormwater BMP Manual.
The site is controlled in two areas; Drainage Area A located adjacent to Gruber Road between
Butner Road and Taylor Street, Drainage Area B located along Spooner Street and along
Butner Road between Spooner and Keerans Street. The primary method for reducing the
discharge rate from Drainage Area A is a Bioretention facility to control the water quality
aspects of the runoff and underground storage in the form of 96" Corrugated Metal Pipe
(CMP) to control the rate and volume control of the higher runoff events. The primary
method for reducing the discharge rate from Drainage Area B is an Underground infiltration
trench to control the water quality aspects of the runoff and underground storage in the form
of 96" Corrugated Metal Pipe (CMP) to control the rate and volume control of the higher
runoff events. (It should be noted that a series of site specific BMP's will provide the
requisite water quality amenities for the development including subsurface infiltration
facilities and a bioretention facility. These water quality BMPs are further disciessed in
section 6 of this report.)
5.1 Storm Sewer Design
The primary storm sewer design will incorporate the 96" CMP to meet the storage
requirements for the developed site to reduce the rate of discharge to that of the pre -
developed conditions rate. A portion of this CMP will also be used for infiltration in Drainage
Area B for water quality requirements and will be placed in a large trench backfilled with
gravel, The infiltration and water quality requirements will be described in detail in section
6.1 of this report. For these sections that will also be used for infiltration there will be 2 feet
of gravel under the CMP and the gravel will be filled to the midsection of the CMP; the rest
will be soil backfill. The gravel trench can thus be used for storage volume minus the
associated volume of the gravel. The gravel has a 40% void space. Subarea A will have 620
lineal feet of 96-inch CMP and Subarea B will have 1500 lineal feet of 96-inch CMP.
124436 Michael Baker Jr., Inc.
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•
US Army Corps of Engineers; Tactical Equipment Maintenance Facility
Stormwater Management Plan (Revised) December 2011
The existing sewer network that the proposed 96 inch pipes will discharge into are sufficient
to handle the new loads and will not suffer any adverse effects. Subarea A discharges into an
existing 30 inch pipe at Gruber and Butner Road. Subarea B discharges into an existing 48"
pipe along Prager Street. Junction boxes will be utilized in conjunction with the storage in the
96 inch pipes to limit the flow rate and volume into the existing systems.
Water Quality Volume (WQv) will be treated through a bio-retention area for Drainage Area
A and 96" CMP infiltration systems integral with the above referenced 96" storage facilities
for Drainage Area B. The first 1.0 inches of rain will be treated for both drainage areas in
accordance with the NCDENR BMP manual to remove 85% of the 'Total Suspended Solids
(TSS). All rainfall events exceeding the 1.0 inch storm will be controlled for volume and rate
reduction to pre -development conditions up to the 10 year storm. Greater storm events will
be allowed to pass through the system without significant flooding or damage to the
stormwater system or facilities in the surrounding area.
The on -site storm drainage has been designed to convey drainage away from each building.
Smaller sized, rubber gasketed Class Ill reinforced concrete pipe (RCN) will be used where
applicable, such as the 18 inch and 24 inch pipes used for the parking lots on Spooner Street.
NCDOT precast storm structures (catch basins, drop inlets, manholes, etc.) will be used in
accordance with the RFP. Please refer to Appendix F for additional information on the storm
sewer design.
6.0 Storniwater Management Facilities and Routing
The table below iternizes the pre- and post -development conditions for the development site
with respect to area, runoff coefficient, and time of concentration:
Table 6.A: Summary of Subareas
Drainage
Subarea
Pre-Develo ed
Post -Developed
Runoff'
Coefficient
Time of
Conc.
(hrs)
Area
(acres)
Runoff
Coefficient
Time of
Conc.
(hrs)
Area
(acres)
AI,RI,
70
0.10
4.48
-
-
-
AmST
-
'
-
92
0.08
4.48
BPRE
70
0.24
11.89
-
-
-
BPOST
-
-
-
94
0.11
11.89
POI
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•
US Army Corps of Engineers; Tactical Equipment Maintenance Facility
Stormwater Management Plan (Revised) December 2011
The orifice outlets in the stormwater detention system will be designed to reduce the rate of
flow from the site to the pre -development conditions or lower as detailed in the NCDENR
Stormwater Manual.
Actual discharge at the POI is slightly less than the pre -developed conditions. The following
tables summarize these results:
Table 6.B: Summary of Storm Routings to POI
Description
Subarea A
Subarea B
Storm Event - 10 year
Storm Event — 10 year
Pre -development Discharge Rate at. POI
(Appendix A)
17.74 cis
30.03 cfs
Post -development Discharge Rate at POI
(Appendix C)
4.65 cfs
16.53 cfs
Post -development — Pre -development =
(3.09 cfs)
(13.50 cfs)
6.1 Water Quality
Several BMPs will provide water quality for this site. The required volume of stormwater to
be mitigated by the facilites has been calculated using the runoff volume generated from 1.0
inch of rainfall frorn impervious surfaces. Thus, the facility for Area A was sized to treat
approximately 4,390 cubic feet of runoff volume. The facility to treat drainage Area B was
sized to treat approximately 20,383 cubic feet of runoff volume, calculations can be found in
Appendix C of' this report. The Bioretention facility has been designed to dewater the cell
within 48 hours. The calculations for the underdrain based on the fill media in the
Bioretention cell as outlined in the NCDENR BMP Manual is included in Appendix C. The
infiltration trench has been designed such that the volume will infiltrate within 40 hours, thus
meeting the requirements of the NCDENR Stormwater BMP Manual, calculations are shown
in Appendix C.
A bioretention basin is basically a filtering device that allows the flow of water to pond and
pass through the device within 48 hours while filtering out the sediment transported by the
runoff to the facility. The system is comprised of a 2' thick soil medium that would allow the
growth of grass or vegetation over a 4" layer of sand and an 8" layer of gravel. Within the
gravel layer is a perforated PVC collection system to drain the basin. The location of this
124436 Michael Baker Jr., Inc.
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US Army Corps of Engineers; Tactical Equipment Maintenance Facility
Stormwater Management Plan (Revised) December 2011
proposed BMP is shown on the attached drawings and the calculations are included in
Appendix F. The bio-retention basin must store the runoff from the first 1.0 inches of rainfall
above the soil media at a ponded depth of 12 inches or less. Using the Simple Method as
outlined in the NCDENR Stormwater BMP Manual the required volume of the ponded area
for the bio-retention basin is 4,390 cu.ft., therefore the surface area of the bio-retention basin
at 12 inches of depth is also 4,390 cu.ft. A detail of the design of this basin and calculations
can be found in Appendix F along with the calculations.
The underground infiltration system will utilize the 96" CMP culverts as the means to store
the volume required to infiltrate. The CMP will be perforated in the sections of culvert that
are designed for infiltration. To allow the infiltration of the initial 1.8 inches of runoff to be
used as an acceptable means to meet the NCDENR water quality standards the soil must have
an infiltration of at least 0.52 inches/hour to be and the Seasonal High Water Table (SHWT)
must be at least 2 feet below the infiltration trench. The drainage Area B was found to have
soils with an infiltration rate of 1,42 inlhr and the seasonal high water table was 18 feet below
grade. This provided an acceptable infiltration rate for this drainage area and a SHWT 6 feet
below the infiltration trench. Details, drawings and calculations for this system can be found
in Appendix F.
The stormwater management facilities, both above and below ground, will be sized to control
and treat the first 1.0" of rain from the contributing impervious drainage areas. Runoff from
all drainage areas will be routed tbrough its respective stormwater management facility to the
Pol.
7.0 Environmental Impacts, Permitting, and Maintenance
7.1 Wetlands and Permitting
Wetlands do not exist on this site.
7.2 NPDES Permit
A Notice of Intent will be applied for this site in accordance with North Carolina Department
of Environmental Protection National Pollutant Discharge Elimination System General Permit.
7.3 Storm Water BMPs - Operation and Maintenance
The operation and maintenance of the infiltration facilities, bioretention facility, and
stormwater detention facilities will be the responsibility of Fort Bragg personnel.
7.3.1 Inspection/Maintenance Frequency
124436 Michael Baker Jr., Inc.
Page 9

US Army Corps of Engineers; Tactical Equipment Maintenance Facility
Stormwater Management Plan (Revised) December 2011
9
The infiltration facilities, bioretention facility, and stormwater detention facilities need to be
cleaned and maintained periodically. Inspect all facilities after the first large storm to
determine whether desired residence time has been achieved. Additionally, the following
typical maintenance activities and frequencies are to be applied:
Infiltration Facilities
Schedule semiannual inspection for the beginning and end of the wet season.
Remove accumulated trash and debris in the catch basins. The frequency of this
activity may be altered to meet specific site conditions.
Each maintenance inspection shall be conducted at least once a year after the wet
season. When sediment is seen, via the maintenance ports, the depth of the sediment
shall be determined either by manual measurement or pre -labeled mark within facility
of at least six inched, the facility should be cleaned. Cleaning shall occur within thirty
days of the date of inspection and will be per the manufacturer's recommendations.
Typically, a vacuum truck will be used to suction out the sediment after re -suspension.
Care should be taken to pump the effluent through a pumped water filter bag, or other
filtering devise, to ensure that sediment laden water is not discharged to any storm
system. All sediment shall be disposed of properly.
Bioretention Facility
Schedule semiannual inspection for the beginning and end of the wet season for
standing water, slope stability, sediment accumulation, trash and debris, and presence
of burrows.
+ Remove accumulated trash and debris in the catch basins and filter and around the
riser pipe of the bio-retention facility during the semiannual inspections. The
frequency of this activity may be altered to meet specific site conditions.
• Trim vegetation at the beginning and end of the wet season and inspect monthly to
prevent establishment of woody vegetation and for aesthetic reasons.
0 Remove accumulated sediment and regrade about every 10 years or when the
accumulated sediment volume exceeds 10 percent of the facility volume. Inspect the
systems each year for accumulated sediment volume.
0
124436
Michael Baker Jr., Inc.
Page 10

US Army Corps of Engineers
Tactical Equipment Maintenance Facility (T EMF)
31-d Brigade Combat Team (BCT) Complex
Fort Bragg, North Carolina
Stormwater Management Plan
(Revised) December 2011
CALCULATIONS CERTIFICATION
1, Ronald iIM. Shirato, P.E., do hereby certify to the best of my knowledge, information and
belief, that the information contained in the accompanying calculatiOIIS has been prepared in
accordance with accepted engincering practice, is true and correct.
GARO�0S31p O�/�•,,�
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Signature
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Date

Subject:_
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Computed by-LI&L—Checked By
Sheet No,-...--L— of
Drawing No
Date L 1A
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S.O. Na
Subject:
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. . .......... .. .. . .. .. .. .. ... . ......... .. .... ........ .. .. ........ Drawing No.—, . .... ..
COMPLIted by,,,.% Checked By _ Date o o i
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t" elf,.

•
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is
Permit No.
(to be provided byDWQ)
III. REQUIRED ITEMS CHECKLIST
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Page/ Plan
Initials Sheet No.
EAZ CE100 1. Plans (1" - 50' or larger) of the entire site showing:
Design at ultimate build -out,
Off -site drainage (if applicable),
Delineated drainage basins (include Rational C coefficient per basin),
Trench dimensions,
Pretreatment system,
High flow bypass system,
Maintenance access,
Proposed drainage easement and public right of way (ROW),
Overflow device, and
Boundaries of drainage easement.
EAZ CG101-CG105 2. Partial plan (1" = 30' cr larger) and details for the infiltration trench showing:
Bypass structure,
Maintenance access,
Basin bottom dimensions,
Basin cross-section with benchmark for sediment cleanout,
Flow distribution detail for inflow,
Vegetated filter, and
Pretreatment device.
EAZ _C-509 3. Section view of the infiltration trench 0" = 20' or larger) showing:
Pretreatment and treatment areas, and
Inlet and outlet structures.
EAZ App. C, Calcs 4. A table of elevations, areas, incremental volumes & accumulated volumes to verify the volume provided.
EAZ App. B 5. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. The
results of the soils report must be verified in the field by DWQ, by completing & submitting the soils
investigation request form. County soil maps are not an acceptable source of soils information.
EAZ CE504 6. A construction sequence that shows how the infitlration basin will be protected from sediment until the
entire drainage area is stabilized.
EAZ App, C, Calcs 7. The supporting calculations.
EAZ App. D 8. A copy of the signed and notarized operation and maintenance (00) agreement.
EAZ NIA 9. A copy of the deed restrictions (if required).
Form SW401-Infiltration Trench-Rev.4
Part III. Required Items Checklist, Page 1 of 1

Permit
(€o be assigned by D WQ)
Ill. REQUIRED ITEMS CHECKLIST
•
Please indicate the page or plan sheet numbers where the supporting dccumenlalicn can Im found. An Incompleto submittal package
will result in
a request for additional Information. This will delay final review and approval of the project. Initial in the space provided
to irdicate the following design
requirements have been met. if the applicant has designated an agent, the agent may initial below. If a
requirement
has not been met, attach justification,
Pagel Plan
Initials
Sheet No,
&fie
CC 100
1. Plans (1" . 50' or larger) of the entire site showirg:
Design at ultimate build -out.
Off -site drainage (if applicable),
Delineated drainage basins (include Rational C coefficient per basin),
Cell dimensions,
Pretreatment system,
High fio:v bypass system,
Nlaintenance access,
Recorded drainage easement and public right el way (ROW),
Clean out pipe locations,
Over(loer device, and
Boundaries of drainage easement.
4FA
CC214=
2. Plan details (V = 30' er larger) for the bicreteiilico cell shoving:
Cell dimensions
pretreatmenl system,
High For bypass system,
Maintenance access,
Recorded drainage easement and public right of way (ROW).
Design at ultimate build-oul,
Off -site drainage (if applicable),
Clean out pipe locations,
Over luo device, and
•
Boundaries of drainage easement.
Indicate the P-Index behveen 10 and 30
3. Section view of the bforetenlion cell (1" = 20' or larger) showing:
Side slopes, 3:1 or lower
Underdrain syslern (if applicable), and
Biorelentioo cell layers {ground level and slope, pre-treatment, pending depth, mulch depth, fill media
depth, washed sand, filler fabric (or olio''king stone if applicable), 457 stone, underdrains (if applicable),
SHIRT [evel(s), end overffo,v structure]
A
i!. A soils report that is based upon an actual field invest.galion, sail borings, and infiltration tests. The
results of the soils report must be verified in the field by DVVQ, by compleling & submilling the soils
investigation request form. County soil maps are not an acceptable source of soils information. All
elevations shall be in feet mean sea level (Imsl). Resui',s of soils tests of bath the planting soil and the in
situ soil must include:
Scll permeability,
Scil composition (% sand. % fines, % organic), and
P-index.
5. A detailed planting plan (V = 20' or larger) prepared by a qualified individual shwling:
A variety of suitable species,
Cud
Sizes, spacing and locations of plantings.
Total quantily of each typo of plant specified.
A planting detail,
The source nursery for the plants, and
Fertilizer and wale€Ing requirements to eslablish vegetation.
EAR
6-
6 A construpliori sequence that shows ho',v the binrelenlion cell will be protected from sedimenl until the
entire drainage area is slatAized.
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7. The supporting ca'culalions (including underdrain calculations, if applicable).
�Y�_D
8. A copy of the sinned and notarized inspection and maintenance (18I.1) agreement
6A 1
Nfq
9. A copy of the deed restriction,
Form S'N401-Moretention-Re•1.7 Part III, Page 1 of 1