SW7100309_HISTORICAL FILE_20210421

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT. NO.
SW
DOC TYPE
❑ CURRENT PERMIT
❑ APPROVED PLANS
ISTORICAL FILE
❑ COMPLIANCE EVALUATION INSPECTION
DOC DATE
�w ze/q/
YYYYMMDD

ROY COOPER
Governor
DIONNE DELLI-GATTI
Secretary
BRIAN WRENN
Director
JJ/' 66'
NORTH CAROLINA
Environmental Quality
April 21, 2021
US Fish and Wildlife Service
Mattamuskeet National Wildlife Refuge
38 Mattamuskeet Road
Swan Quarter, NC 27885
Dear Sir:
Subject: Stormwater Permit Renewal
Stormwater Management Permit SV 7100309
Mattamuskeet National Wildlife Refuge OfficeNisitor Center
Hyde County
A Division of Energy, Mineral, and Land Resources file review has determined that
Stormwater Permit SV 7100309 for a stormwater treatment system consisting of a wet
detention pond serving the Mattamuskeet National Wildlife Refuge OfficeNisitor located
at 38 Mattamuskeet Road, Swan Quarter, NC expires on December 31, 2021. This is a
reminder that permit renewal applications are due 180 days prior to expiration. We do
not have a record of receiving a renewal application.
Please submit a completed permit renewal application along with a $505.00 fee for
permit renewal. Permit application forms for renewal can be found on our website at:
https://deq.nc.gov/about/divisions/energy-mineral-and-land-
resources/stormwater/stormwater-program/post-construction-2. North Carolina General
Statutes and the Coastal Stormwater rules require that this property be covered under a
stormwater permit. Failure to maintain a permit subjects the owner to assessment of
civil penalties.
If you have questions, please feel free to contact me at [phone]. 1 will be glad to
discuss this by phone or meet with you. If you would like, I can e-mail you a copy of the
application forms. You can request a copy by e-mailing me at
roger.thorpeCcDncdenr.gov.
Sincerely,
Roger K. TT orph e
Environmental Engineer
North Carolina Department of Environmental Quality I Division of Energy. Mineral and Land Resources
Washington Regional Office 1 943 Washington Square Mall I Washington, North Carolina 27889
252.946.6481
_D Nn ���
M��N'ina;w
�+��—�-_�

Dewberry
1 _
Dewberry & Davis. Inc.
2301 Rexwoods Drive, Suite 200
Raleigh, NC 27607-3366
919.881.9939
919.881.9923 fax
www.dewberry.corn
September 27, 2011
Mr. Samir Dumpor, P.E.
Environmental Engineer II
NC Division of Water Quality
Washington Regional Office
943 Washington Square Mall
Washington, NC 27889
RECEIVED
SEP 2 9 2011
DWQ-Will \O
Reference: US Fish and Wildlife Service
Mattamuskeet National Wildlife Refuge Office/Visitor Center and Out -Buildings
Stormwater Permit Certification
Dewberry Project # 50020545
Dear Mr. Dumpor:
Please fiold.ernclosed the Stormwater Permit Certification for the Mattamuskeet National Wildlife Refuge
Office/Visitor Center and Out -Buildings project (Stormwater Permit No. SW7100309).
` r
Should you have any questions or need additional information, please call me at [phone].
Sincerely,
Dewberry & Davis,
Inc.
?atetphewest, P!EqLEAP BD+C
Project Manager
Enclosures
Cc: Jerry Hardison, Hyde County Building Inspections
Walter Cowan, US Fish and Wildlife Service
Jerry Fringeli, US Fish and Wildlife Service
Steve Thomas, Centennial Contractors Enterprises, Inc.
Scott McGrew, Centennial Contractors Enterprises, Inc.
Gary Sylvester, Centennial Contractors Enterprises, Inc.
Henry Winters, Centennial Contractors Enterprises, Inc.
Mark Scott, PSA-Dewberry
P.\50020505\Adm\Correspondentt\Letters\2011.09.27 - Dumpor.Stormwater Certifkatlon.dwx

iioS p S 9j8

A A
�r
NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Coleen H. Sullins Dee Freeman
Governor Director Secretary
March 24. 2010
Mr. Jerry Fringeli, Assistant Refuge Manager
U.S. Fish and Wildlife Service
38 Mattamuskeet Road
Swan Quarter, INC 27885
Dear Mr. Fringeli:
Subject: Stormwater Permit No. SW7100309
Mattamuskeet National Wildlife Refuge Office [Visitor
Center and Out -Buildings
High Density / Redevelopment - Wet Pond Project
Hyde County
The Washington Regional Office received a complete Stormwater Management Permit
Application for Mattamuskeet National Wildlife Refuge / Visitor Center and Out -Buildings on
March 16, 2010. Staff review of the plans and specifications has determined that the project,
as proposed, will comply with the Stormwater Regulations set forth in Session Law 2008-211
and Title 15A NCAC 2H.1000. We are forwarding Permit No. SW7100309 dated March 24,
2010, for the construction of the subject project.
This permit shall be effective from the date of issuance until March 24, 2020, and shall be
subject to the conditions and limitations as specified therein. Please pay special attention to
the Operation and Maintenance requirements In this permit. Failure to establish an adequate
system for operation and maintenance of the stormwater management system will result in
future compliance problems.
If any parts, requirements, or limitations contained in this permit are unacceptable, you have
the right to request an adjudicatory hearing upon written request within thirty (30) days
following receipt of this permit. This request must be in the form of a written petition,
conforming to Chapter 150E of the North Carolina General Statutes, and filed with the Office of
Administrative Hearings, P.O. Drawer 27447, Raleigh, NC 27611-7447. Unless such demands
are made this permit shall be final and binding.
If you have any questions, or need additional information concerning this matter, please
contact Samir Dumpor, or me at [phone].
incer y,
7�1 d1
Regional Supervisor
Surface Water Protection Section
AH/ so: K:\WQS\STORMWATER\SD\SW7100309
cc: Aichael Hanson, PE, (Dewberry, 2301 Rexwoods Drive, Suite 200, Raleigh, NC
27607)
Hyde County Building Inspections
Washington Regional Office
Central Files
Nurth Carolina Division of P'itcr ounlity Intema u_%�gncvautJquidhty qrg
9,13 Washington Squirt Mall Phone: 2i2-9a6-tiJN l One
Washingiun, NC 27889 FAX 252-9J6-9215 Noi tli Car-oj/t/n a
An Equal Opportunity/AHinnalive Aclion Employer-50% P.ecycledll0°/ Post Consumer Paper X tia- l&

State Stormwater Management Systems
Permit No. SW7100309
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
STATE STORMWATER MANAGEMENT PERMIT
HIGH DENSITY DEVELOPMENT
In accordance with the provisions of Article 21 of Chapter 143, General Statutes of
North Carolina as amended, and other applicable Laws, Rules, and Regulations
PERMISSION IS HEREBY GRANTED TO
U.S. Fish and Wildlife Service
Mattamuskeet National Wildlife Refuge Office/Visitor Center and Out -Buildings
Hyde County
iiiiiii 101Earm ■
construction, operation and maintenance of one wet detention pond in compliance with
the provisions of Session Law 2008-211 and 15A NCAC 2H .1000 (hereafter referred to
as the "stormwater rules') and the approved stormwater management plans and
specifications and other supporting data as attached and on file with and approved by
the Division of Water Quality and considered a part of this permit.
This permit shall be effective from the date of issuance until March 24, 2020, and shall
be subject to the following specified conditions and limitations:
I. DESIGN STANDARDS
This permit is effective only with respect to the nature and volume of stormwater
described in the application and other supporting data.
This stormwater system has been approved for the management of stormwater
runoff as described in Section 1.7 of this permit. This is project is considered as
a Partial Redevelopment project. The Existing Impervious area on this site is
71,263 square feet, while the Proposed Impervious Area is 105,852 square feet,
hence the Required Impervious Area to be treated by stormwater controls is
34,589. The stormwater control has been designed to handle the runoff from
41,818 square feet of impervious area.
3. The tract will be limited to the amount of built -upon area indicated in Section I. of
this permit, and per approved plans.
4. All stormwater collection and treatment systems must be located in either
dedicated common areas or recorded easements. The final plats for the project
will be recorded showing all such required easements, in accordance with the
approved plans.
The runoff from all built -upon area within the permitted drainage area of this
project must be directed into the permitted stormwater control system.
The built -upon areas associated with this project shall be.located at least 50 feet
landward of all perennial and intermittent surface waters.
Page 2 of 7

, . . - y ,,,..,,...,.. ,,,
Permit No. SW7100309
The following design criteria have been provided in the wet detention pond and
must be maintained at design condition:
a. Drainage Area, ft2:
b. Total Impervious Surfaces, ft2:
C. Design Storm, inches:
d. Pond Depth - average, feet:
e. TSS removal efficiency:
f. Permanent Pool Elevation, FMS�:
g. Permanent Pool Surface Areq, ft
h. Permitted Storage Volume, ft :
i. Temporary Storage Elevation, FMSL:
j. Predevelopment 1 year 24 hour:
k. Post development 1 year 24 hour:
I. Controlling Orifice:
M. Permitted Forebay Volume, ft':
n. Receiving Stream/River Basin: UT to
o. Stream Index Number:
P. Classification of Water Body:
II. SCHEDULE OF COMPLIANCE
63,169
41,818
1.5
3.0
90%
0.90
8,591
5,186 at temporary pool el
1.45
4.20 ft'/s
4.03 ft'/s
1.4"0 pipe
4,512
Outfall Canal / Tar -Pam River basin
29-57-1
"SC"
The stormwater management system shall be constructed in its entirety,
vegetated and operational for its intended use prior to the construction of any
built -upon surface.
During construction, erosion shall be kept to a minimum and any eroded areas of
the system will be repaired immediately.
The permittee shall at all time provide the operation and maintenance necessary
to assure the permitted stormwater system functions at optimum efficiency. The
approved Operation and Maintenance Plan must be followed in its entirety and
maintenance must occur at the scheduled intervals including, but not limited to:
a. Semiannual scheduled inspections (every 6 months).
b. Sediment removal.
C. Mowing and re -vegetation of slopes and the vegetated filter strip.
d. Immediate repair of eroded areas.
e. Maintenance of all slopes in accordance with approved plans and
specifications.
f. Debris removal and unclogging of outlet structure, orifice device, level
spreader, filter strip, catch basins and piping.
g. Access to the outlet structure must be available at all times.
4. Records of maintenance activities must be kept for each permitted BMP. The
records will indicate the date, activity, name of person performing the work and
what actions were taken.
5. The permittee shall submit to the Division of Water Quality an annual summary
report of the maintenance inspection records for each BMP. The report shall
summarize the inspection dates, results of the inspections, and the maintenance
work performed at each inspection.
6. Access to the stormwater facilities shall be maintained via appropriate
easements at all times.
The facilities shall be constructed as shown on the approved plans. This permit
shall become void unless the facilities are constructed in accordance with the
conditions of this permit, the approved plans and specifications, and other
Page 3 of 7

State Stormwater Management Systems
Permit No. SW7100309
supporting data.
Upon completion of construction, prior to issuance of a Certificate of Occupancy,
and prior to operation of this permitted facility, a certification must be received
from an appropriate designer for the system installed certifying that the permitted
facility has been installed in accordance with this permit, the approved plans and
specifications, and other supporting documentation. Any deviations from the
approved plans and specifications must be noted on the Certification. A
modification may be required for those deviations.
9. If the stormwater system was used as an Erosion Control device, it must be
restored to design condition prior to operation as a stormwater treatment device,
and prior to occupancy of the facility.
10. The permittee shall submit to the Director and shall have received approval for
revised plans, specifications, and calculations prior to construction, for any
modification to the approved plans, including, but not limited to, those listed
below:
a. Any revision to any item shown on the approved plans, including the
stormwater management measures, built -upon area, details, etc.
b. Project name change.
C. Transfer of ownership.
d. Redesign or addition to the approved amount of built -upon area or to the
drainage area.
e. Further subdivision, acquisition, lease or sale of all or part of the project
area. The project area is defined as all property owned by the permittee,
for which Sedimentation and Erosion Control Plan approval or a CAMA
Major permit was sought.
f. Filling in, altering, or piping of any vegetative conveyance shown on the
approved plan.
11. The Director may notify the permittee when the permitted site does not meet one
or more of the minimum requirements of the permit. Within the time frame
specified in the notice, the permittee shall submit a written time schedule to the
Director for modifying the site to meet minimum requirements. The permittee
shall provide copies of revised plans and certification in writing to the Director
that the changes have been made.
12. The.permittee shall submit final site layout and grading plans for any permitted
future areas shown on the approved plans, prior to construction.
13. A copy of the approved plans and specifications shall be maintained on file by
the Permittee at all times.
III. GENERAL CONDITIONS
This permit is not transferable except after notice to and approval by the Director.
In the event of a change of ownership, or a name change, the permittee must
submit a completed Name/Ownership Change form, to the Division of Water
Quality, signed by both parties, and accompanied by supporting documentation
as listed on page 2 of the form. The project must be in good standing with the
Division. The approval of this request will be considered on its merits and may or
may not be approved.
The permittee is responsible for compliance with all permit conditions until such
time as the Division approves the transfer request.
Failure to abide by the conditions and limitations contained in this permit may
subject the Permittee to enforcement action by the Division of Water Quality, in
Page 4 of 7

OWU7 JWIIIIWdR71 IVIdIIdyt-111WII JyS,MIIIJ
Permit No. SW7100309
accordance with North Carolina General Statute 143-215.6A to 143-215.6C.
4. The issuance of this permit does not preclude the Permittee from complying with
any and all statutes, rules, regulations, or ordinances, which may be imposed by
other government agencies (local, state, and federal) having jurisdiction.
5. In the event that the facilities fail to perform satisfactorily, including the creation
of nuisance conditions, the Permittee shall take immediate corrective action,
including those as may be required by this Division, such as the construction of
additional or replacement stormwater management systems.
6. The permittee grants DENR Staff permission to enter the property during normal
business hours for the purpose of inspecting all components of the permitted
stormwater management facility.
7. The permit issued shall continue in force and effect until revoked or terminated.
The permit may be modified, revoked and reissued or terminated for cause. The
filing of a request for a permit modification, revocation and re -issuance or
termination does not stay any permit condition.
8. Unless specified elsewhere, permanent seeding requirements for the stormwater
control must follow the guidelines established in the North Carolina Erosion and
Sediment Control Planning and Design Manual,
9. Approved plans and specifications for this project are incorporated by reference
and are enforceable parts of the permit.
10. The issuance of this permit does not prohibit the Director from reopening and
modifying the permit, revoking and reissuing the permit, or terminating the permit
as allowed by the laws, rules and regulations contained in Session Law 2008-
211, Title 15A NCAC 2H.1000, and NCGS 143-215.1 et.al.
11. The permittee shall notify the Division of any name, ownership or mailing
address changes at least 30 days prior to making such changes.
12. This permit shall be effective from the date of issuance until March 24, 2020.
Application for permit renewal shall be submitted 180 days prior to the expiration
date of this permit and must be accompanied by the processing fee.
Permit issued this the 24th day of March, 2010.
NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION
U \� ItQ1�(�i - for
Zoleen H. Sullins, Director
Division of Water Quality
By Authority of the Environmental Management Commission
Stormwater Permit No. SW7100309
Page 5 of 7

ror uenn use<UNLY
Reviewer. : )et 1 ✓
North Carolina Department of Environment and Submit: P -Y_4�D
s' Natural Resources
NC®ENR Request for Express Permit Review Time:
Confirm.
IN all the information below and CHECK the Permits) you are requesting for express review. FAX or Email the completed form to Express
oordinator along with a completed DETAILED narrative, site plan (PDF file) and vicinity map (same items expected in the application package
of the project location. Please include this form in the application package.
• Asheville Region -Alison Davidson 828-2964698;alison.davidson®ncdenr.Qov
• Fayetteville or Raleigh Region -David Lee 919-791-4203; david.lee®ncdenr.gov
• Mooresville & -Patrick Grogan 704-663-3772 or [e-mail]
• Washington Region -Lyn Hardison 252-946.9215 or lyn.hardison®ncdenr.gov
• Wilmington Region -Janet Russell910-350.2004 or [e-mail]
NOTE., Project application received after 12 noon will be stamped in the following work day.
Permits of request
SW
SW
SW
SW
SW
1,6 2010
Project Name: MATTAMUSKEET NATIONAL WILDLIFE REFUGE OFFICE/VISITOR STATION County: HYDE IIaa,, ,ppee ppA�I�
Applicant: JERRY FRINGELI Company: US FISH AND WILDLIFE SERVICES HIC DEN W
Address: 38 MATTAMUSKEET ROAD City: SWAN QUARTER, State: NC Zip: 27885
Phone: [phone], Fax:[phone], Email: any fringeli@fALM
Physical Location: OFFICENISITOR STATION AND OUT -BUILDINGS, MATTAMUSKEET ROAD Latitude 35.4513 Longitude 76.1767
Project Drains into TRIBUTARY TO THE GUTFALL CANAL waters — Water classification SC (for classification see-
hflp:Hh2o.enr.state.nc.us/bims/reports/reportsWB.htmi)
Project Located in TAR PAMILLICO River Basin. Is project draining to class ORIN waters? N , within'h mile and draining to class SA waters N or within 1
mile and draining to class HOW waters? N ^ I
Engineer/Consultant: MATT WEST Company: DEWBERRY 30 J
Address: 2301 REXWOODS DRIVE SUITE 200 City: RALEIGH, State: NC Zip: 27607
Phone:[phone], Fax: [phone], Email: [e-mail]
SECTION ONE: REQUESTING A SCOPING MEETING ONLY
Scoping Meeting ONLY ❑ DWO, ❑ DCM, ❑ DLR, ❑ OTHER:
CTION TWO: CHECK ONLY THE PROGRAM (S) YOU ARE REQUESTING FOR EXPRESS PERMITTING
® 401 Unit ❑ Stream Origin Determination: _ If of stream calls - Please attach TOPO map marking the areas in questions
❑ Intermittent/Perennial Determination: _ # of stream calls — Please attach TOPO map marking the areas in questions
® 401 Water Quality Certification ❑ Isolated Wetland (_linear It or _acres)
❑ Riparian Buffer Authorization ❑ Minor Variance ❑ Major General Variance
® State Stormwater ❑ General ❑ SFR, ❑ SFR < 1 ac. ❑Bkhd & Bt Rmp, ❑ Clear & Grub, ❑ Utility. [-]Other
❑ Low Density ❑ Low Density -Curb & Gutter _ # Curb Outlet Swales ❑ Off -site [SW (Provide permit #)I
® High Density -Detention Pond 1 # Treatment Systems ❑ High Density -Infiltration _ #Treatment Systems
❑ High Density -Bio-Retention _ # Treatment Systems ❑ High Density -SW Wetlands _ # Treatment Systems
❑ High Density -Other _ # Treatment Systems /❑ MOD:❑ Major ElMinor ❑ Plan Revision ❑ Redev. Exclusion SW (Provide permit a)
❑ Coastal Management ❑ Excavation & Fill ❑ Bridges & Culverts ❑ Structures Information
❑ Upland Development ❑ Marina Development ❑ Urban Waterfront
® Land Quality ® Erosion and Sedimentation Control Plan with 5 acres to be disturbed.(CK If 2-1gK2c (for DENR use)) s 32
SECTION THREE - PLEASE CHECK ALL THAT IS APPLICABLE TO YOUR PROJECT (for both scoping and express meeting request)
Wetlands on Site ® Yes ❑ No
Wetlands Delineation has been completed: ® Yes ❑ No
US ACOE Approval of Delineation completed: ❑ Yes ® No
Received from US ALOE ❑ Yes ® No
For DFNR use
Fee Split for multiple permits: (Check # Zqq 41 °I I
Buffer Impacts: ® No ❑ YES: _acre(s)
Isolated wetland on Property ❑ Yes ® No
404 Application in Process w/ US ACOE: ® Yes ❑ No Permit
Total Fee Amount
SUBMITTAL DATES
Fee
I
I SUBMITTAL DATES
Fee
A
$
Variance (❑ Maj; ❑ Min)
$
W ( HD, ❑ LD, ❑ Gen)
$(;7�yat?
401:
_
$ TOOVAI
LOS
$/' j•
Stream Deter,_
$
NCDENR EXPRESS March 2009

n
L.J
STORMWATER MANAGEMENT PLAN
MATTAMUSKEET NATIONAL WILDLIFE REFUGE
OFFICE/VISITOR CONTACT STATION AND OUT -BUILDINGS
SWAN QUARTER, NC
DEW13ERIZY PROJECT NO. 50020545
March 10, 2010
Prepared by:
Dewberry & Davis, Inc.
2301 Rexwoods Drive
Suite 200
Raleigh, NC 27607
919.881.9939 ph
919.881.9923 fax
www.dewberry.com
EXPRES.S
MAR 1,6 2010
me ®EigR
i
s
EL A
IIII111

• Table of Contents
Introduction.................................................................................................................................................. 1
ProjectBackground...................................................................................................................................... 1
Review of Stormwater Runoff Control Regulations.................................................................................... 2
Summary of Discharge Evaluation and Design of Treatment Facility......................................................... 3
Table
Table l : Calculation of treatment volume required by DWQ for the project site........................................2
Appendix
Appendix A
Project Location Map
Exhibit A — Existing Basin Drainage Map
Exhibit B — Existing Impervious Area
Exhibit C — Proposed Impervious Area
Exhibit D — Proposed Drainage Basin B-2
Appendix B
Letters/Emai Is
Geotechnical Report
Supplementary Information
Stormwater Management Permit Application Form
• Operation and Maintenance Form
Express Permitting Form
Appendix C
Discharge Calculations Spreadsheet
Chain Saw Routing Spreadsheet
Supplement_WetBasin_Rev.8 Spreadsheet
n
U

• MATTAMUSKEETNATIONAL WILDLIFE REFUGE
OFFICL/VISITOR CONTACT STATION AND OUT -BUILDINGS
SWAN QUARTER, NC
Stormwater Management Plan Narrative and Calculations
March 10, 2010
Introduction
This document summarizes the stormwater management plan for the replacement of the Maintenance
Garage and Ranger Office at the Mattamuskeet National Wildlife Refuge. The project consists of the
construction of a 4,800 sq. ft. wood framed OfficeNisitor Contact Center, a 6,400 sq. ft. pre-engineered
Maintenance Shop, a 4,800 sq. ft. pre-engineered Equipment Storage Shed, and a 1,200 sq. ft. pre-
engineered Equipment Storage Shed. Work associated with the project includes demolition of existing
buildings and all site required improvements to accommodate the new facilities noted above. The
National Wildlife Refuge tract acreage is 50,180 acres in total area. The project site is 4.77 acres
consisting of approximately 34% impervious area.
The project site currently contains six (6) structures, two (2) concrete pads, two (2) storage sheds and
gravel roads and parking areas. The proposed plan generally includes the removal of four (4) of the
existing structures, the two (2) storage sheds and two (2) concrete pads. These will be replaced by two
(2) structures, two (2) storage sheds, a paved parking area and expanded gravel roads and parking areas.
The existing and proposed plans are included in the Appendix A.
The proposed improvements will increase the site impervious cover by more than 10% when compared to
existing conditions. Based on the discussions with staff at the Washington Regional Office of NCDENR
Division of Water Quality the stormwater treatment volume for this re -development site is therefore based
on the volume generated by 1.5 inches of runoff from the difference between the existing and proposed
impervious area. The impervious area increase is 34,588 SF or an increase of 49%.Therefore, the
required treatment volume for the site is 4,324 CF.. The Best Management Practices (BMP) for the
project site is a Wet Detention Basin (BMP) that will treat 5,424 CF of volume. Due to limited space and
extremely flat terrain on the existing site only a portion of the site will drain to the BMP. The
contributing area is from Basin B (as shown in Appendix A). The runoff captured from this area exceeds
the required site treatment volume. This BMP collects runoff from the new impervious areas on the site to
greatest practical extent. The remaining areas will continue to discharge to existing outfalls.
Included in the Stormwater Management Plan Narrative is review of DWQ State Stormwater regulations,
summary of the estimated peak flows and routing summary through the proposed detention facility.
Project Background
The project site is located in Swan Quarter, Hycle County, NC roughly at the intersection of Mattamuskeet
Refuge Road and Outfall Canal Road.
The project site falls within the Tar Pamlico River Basin. The streams/canals/ lake located nearby the
project site are tributaries to the Outfall Canal, Outfall Canal, and Lake Matta III uskeet. These water
bodies are classified under category SC (All tidal salt waters protected for secondary recreation such as
fishing, boating, and other activities involving minimal skin contact; fish and noncommercial shellfish
consumption; aquatic life propagation and survival; and wildlife). The index numbers of Outfall Canal
and Lake Mattamuskeet are29-57-1 and 29-57-1-1. The existing site discharges to ACEjurisdictional
canals that are tributary to the Outfall Canal. DWQ staff has confirmed due to the nature of these man-
Mattamuskeet National Wildlife Refuge Office/Visitor Station and Out -Buildings Page I of
a
Stormwater Managemenl Plan Narrative

made canals and lack of navigable connection to Waters of the State Tar -Pam buffers will not apply. It
was also confirmed with Coastal Zone Management that CAMA rego
ulations do not apply beyond the
limits of the Outfall Canal. Therefore, no CAMA concurrence is required for the project.
Review of Stormwater Runoff Control Regulations
This site predominantly replaces existing impervious areas with new impervious areas. An overall
increase of impervious area occurs from the new development. Therefore, this re -development project
provides for post development runoff peak for the site to be equal to the pre -development runoff peak for
I year/ 24 hour storm event and treatment of 1.5 inches of runoff from the increased impervious area.
As noted above "far -Pam buffers do not apply to the canals along the perimeter of the site. A small area
on the northern boundary of the site is within the Outfall Canal buffer area as shown in Appendix A
(Sheet C-107). "there are wetlands located on the project site as shown in Appendix A (sheet C-101 and
C-103). Coastal Management (CAMA) permitting is also not required for the site. Letters/emails from the
agency are included in Appendix B.
Since the project site is already a developed site (34 % impervious or high density) and the proposed
project is a re -development of the existing impervious area the normal treatment volume based on the
total impervious area is not applicable to this project site. It should be noted that not all new impervious
area runoff is treated by the BMP, but the new impervious area will be treated through the BMP to the
maximum practicable extent and the total treatment provided exceeds the volume required. Notes from
conversations with DWQ staff summarizing the requirements for the project site are included in Appendix
B.
• "file existing drainage patterns for this site route runoff to threejurisdictional canals. "fhere is no
stonmvater treatment currently provided on the site. Due to the disparate locations of the redeveloped
structures it was not practical to direct all runoff from the new development to the BMP. However, the
BMP does collect runoff from the majority of the new buildings and a majority of the expanded gravel
parking area.
The treatment volume is based on the difference between the existing and proposed impervious area
volume generated by 1.5 inches of precipitation depth, which is calculated as 4,324 CIF for the entire site.
The proposed BMP for the project site will be treating 5,424 CIF of volume from Basin B. which exceeds
the required treatment volume and provides compensatory treatment for all areas that drain to existing
outfalls. The new BMP provides treatment for the greatest practical extent of the new development on the
site.
Table 1: Calculation of treatment volume required by DWQ for the project site
Proposed Impervious Area
105,852
SF
Existing Impervious Area
71,263
SF
Difference in Impervious Area
34,588
SF
Required Treatment Volume ( Costal 1.5-inches)
4-324
CIF
The project site is divided into two sub -basins- Basin A and B as shown in Exhibit A — L'-xisting Drainage
Basin Map in Appendix A. Exhibit B shows the existing impervious area of 1.64 acres within the existing
basins on site also in Appendix A. The site improvements noted above will increase the site impervious
• area to a total of 2.43 acres as shown in Exhibit C in Appendix A. Finally, basin B-2 is shown in Exhibit
D in Appendix A which drains to the BMP. This basin is equivalent to the area required to generate the
Mattatmiskeet National Wildlife Refuge Office/Visitor Station and Out -Buildings Page 2 of
Stormwater Manaaemem flan Narrative

•
treatment volume of 4,324 cf which is the required treatment volume from the clonge in impervious area
on the entire site.
Summary of Discharge Evaluation and Design of Treatment Facility
The project site is divided into two sub -basins- Basin A and B as shown in Exhibit A — Existing Drainage
Basin Map in Appendix A. As previously discussed above, it was decided to provide the treatment for
that portion of Basin B (B-2) which is equivalent to the area that will generate the treatment volume of
4,324 CP required for the change in impervious area on the entire site. Therefore, no treatment facility or
treatment calculations were performed for Basin A or B-1.
Peak discharge rates and runoff volume were calculated for Basin B-2 using the Rational Method and
SCS Method as outlined in Chapter three of the NCDWQ Stormwater Best Management Practices
Manual (updated on July 16, 2009). SCS method parameters such as Curve Numbers and time of
concentration were determined from site surveys, soil maps and aerial photography. Precipitation depth
and intensity were obtained from the National Oceanic and Atmospheric Administration (NOAA)
website. The basin runoff parameters and calculations are included in Appendix C.
The selected BMP for Basin B-2 is a Wet Detention Basin (BMP) as defined in Chapter 10 of the
NCDWQ Stormwater Best Management Practices Manual (updated on June16, 2009). This BMP will
reduce the post development flows to the pre -development flows for 1 year/ 24 hour storm and provide
treatment for 1.5 inches of runoff volume. The BMP was also designed to control the 100 year /24 hour
event and provide 1-foot freeboard from the facility. Basin B-2 is approximately 0.96 acres in land area.
The existing impervious area of the Basin B-2 is 0.20 acres and the proposed impervious area is 0.96
acres which includes the BMP. The required treatment volume for basin B-2 is 4,966 CF . A pollutant
removal efficiency of 90% Total Suspended Solids (TSS) was used to calculate surface area/drainage area
ratio for permanent pool in the Coastal region since the outflow from the wet detention basin (BMP)
discharges into an existing surface water. An onsite soil evaluation was performed to determine the
seasonal high water table and subsurface conditions by ECS CAROLINAS, LLP on July 22, 2009. The
soils report established the SH WL at elevation 1.4 feet, NGVD. The geotechnical report is included in
Appendix B. The routing through the wet detention basin (BMP) was performed using Chainsaw method
by Dr. H. Rooney Malcolm. The post -development discharge for the I year/ 24 hour storm is 4.03 cfs
which is less than the pre development discharge for the I year/ 24 hour storm of 4.2 cfs. Detailed
calculations are included in Appendix C.
The various wet detention basin (BMP) design criteria elevations and corresponding areas for the
different zones are included in Appendix C. The control structure for the wet detention basin is a CMP
riser and barrel structure. The detention storage will be recovered via an orifice in the face of the riser
barrel. Both the drawdown orifice and overflow orifice are fitted with floating debris screening control
devices.
Mattamuskeet National Wildlife Refuge Office/Visitor Station and Out -Buildings Page 3 of
Stormwater Manogement Plan Narrative

Appendix A
Project Location Map
Drainage Maps
Existing and Proposed Impervious Area Maps

PROJECT LOCATION MAP
•

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3 2652
N• Custom Soil ikource Report
Sqwp
Map Sra, 1: 4,136 f paled m A dze (6. S x W) sheet.
N Mete,s
0 50 100 200 300
feet
0 250 500 1,000 1,500
35- 2T 14'
35' 26 53"

0 0 0

• Custom Soil *urce Report •
MAP LEGEND
Area of Interest (AOq
Area of Interest (AOIj
Soils
Soil Map Units
Special
Point Features
PJ
Blowout
®
Borrow Pit
X
Clay Spot
♦
Closed Depression
?(,
Gravel Pit
..
Gravelly Spot
®
Landfill
A
Lava Flow
,6
Marsh or swamp
R'
Mine or Quarry
op
Miscellaneous Water
p.
Perennial Water
.�
Rock Outcrop
}
Saline Spot
Sandy Spot
Severely Eroded Spot
0
Sinkhole
Slide or Slip
0
Sonic Spot
a
Spoil Area
Q
Stony Spot
('p Very Stony Spot
* Wet Spot
Other
Special Line Features
Gully
Shon Steep Slope
Other
Political Features
® Cities
Water Features
Oceans
Streams and Canals
Transportation
Rails
.+y+ Interstate Highways
US Routes
Major Roads
Local Roads
Map Scale: 1:4,730 if printed on A size (8.5" x 11 ") sheet.
The soil surveys that comprise your AOI were mapped at 1:24,000.
Please rely on the bar scale on each map sheet for accurate map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL: http:/Iwebsoilsu"ey.nres.usda.gov
Coordinate System: UTM Zone 18N NAD83
This product is generated from the USDA-NRCS certified data as of
the version date(s) listed below.
Soil Survey Area: Hyde County, North Carolina
Survey Area Data: Version 10, Jan 9, 2008
Date(s) aerial images were photographed: 8/24/2006
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.

Custom Soil Resource Report
• Map Unit Legend
Hyde County, North Carolina (NC095)
Map Unit Symbol
Map Unit Name
Acres in AOI
Percent of AOI
EaA
Engelhard loamy very fine sand, 0 to 2 percent
slopes, rarely flooded
5.6
5.7%
EnA
Engelhard loamy very fine sand, 0 to 2 percent
slopes, frequently flooded
39.8
40.1 %
Ud
Udorthents, sandy, rarely flooded
49.9
50.2%
WyA
Wysocking very f ne sandy loam, 0 to 3 percent
slopes, rarely flooded
4.1
4.1 %
Totals for Area of Interest
99.5
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 forthe 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
10

•
•
GENERAL NOTES
I. ME MNTRACTON SHALL HAVE A COMPLETE SET OF CONfNILT DOCUMENTS AS
WELL AS ALL APPROVALS µ0 PERMITS ON THE JOB SEE AT ALL MAE5.
2. THE CONTRACTOR IS MSPON9BLE FOR ALL LAYOUT WORK REWIRED TO
PROPERLY CONSTRUCT ME WORK. AIL INTERIOR SNA L REMAIN MTNE DURING
CONSTRUCTION UNLESS OTHERWISE NOTED. CONTRACTOR SHALL ENSURE TINT
ANY LINES FEEDING OTHER BUILDINGS REMAIN INTACT AND ARE CAPABLE OF
BEING "WANED.
]. WNTPACTO! SHALL MAKE DAIRY EFTORT TO SAVE PROPERTY IRONS,
E MONUMENTS, OTHER PERMANENT POINTS AND ENDS OF REFERENCE AND
CONSTRUCTION STAKES. PROPERTY IRONS, MONUMENTS, AND OTHER
PERMANENT POINTS OF REFERENCE DESTROYED BY THE CONTRACTOR SHALL BE
REPLACED BY A NORTH GARDENA LICENSED LAND SURVEYOR AT ME
COMPACTOR'S EXPENSE
a. 36' MINIMUM COVER SHALL BE PROADED OVER ALL WATER ONES AND SEWERt
ONES UNLESS SHOWN OTHERWISE
5. CONIRACTOR SHALL INSTALL MEASURES AS NECES I DURING CONSTRUCTION
FOR SMIMENTATON µ0 EROSION CONTROL
6. ME CONTRACTOR SHALL RESTORE ME DISTURBED AREA TO EXISTING OR
FW6HCO GRADE UNLESS SHOWN OTHERWISE ON ME DRAMNGS.
Z. CONTRACTOR SI141 SALVAGE A- SIGNS WITHW CONSiRUCTON UMIR AND
REINSTALL AS DIRECTED BY OWNER. -
B. ALL WRINGS ARE, NOT SHOWN ON ME DRAWINGS. ME COMPACTOR SOUL BE
RESPONSIBLE MR PROVIDING AND INSTALNG A31 FDTINGS NECESSARY TO
COMPLETE ME WORK.
9. ME CODPM.TOR SAL MAIM" SEPARATION BEIWEDR SEWERS µ0 WATER
MANS AS FOLLOWS:
(A
WATER MANS SHALL BE LAID AT LEASE TO' IATEML_Y FROM EXISTING OR
PROPOSED SEWERS. UNLESS LOCI. CONDITIONS OR BARRIERS
D PREVENT A 10' LATERAL SEPARATION -IN WH" CASE:
(1) ME WATER MAN IS WO IN A SEPARATE FRENCH, WITH THE
EIEVAMN OF ME MORON O ME WATER MAIN AT LEAST 18' ABOVE
ME TOP OF ME SEWER. OR
(2) ME WATER MAN IS LAID IN ME SAME FRENCH AS ME SEWER WMI
ME WATER MAIN LOOTED AT ONE SOLE ON A BENCH Of UNDISTURBED
EARTH, AND WITH ME ELEVATION OF ME BOTTOM OF ME WATER MAN
AT LEAST 18' ABOVE ME MR OF ME SEWER-
(B) DPGSSING A WATER MAN OVOI A SEWER
WHENEVER E IS NECESSARY FOR A WATER AWN TO CROSS OVER A
SEWER. ME WATER MAIN SOUL BE LAID AT SUCH AN OENATION THAT
ME BOTTOM TH
E E WATER MAN IS IB' ABOVE ME TOP OF ME
SEWER. UNLESS LOCAL CONDITIONS OR BARRIERS PREVENT AN 18'
VERTICAL SEPARATION - IN WHICH CASE BOTH ME WATER MIN µ0
JUINIS MAI µE EQUIVALENT M WATER LAN STµWDS
FOR A DISLMCE OF 10' ON EACH SIDE OF THE POINT OF CR054NG.
(C) fpO551NG A WATER MN LINGER A SEWER
WHENEVER N IS NECESSARY FOR A WATER WIN TO BE CROSSED UNDER
A SEWER. BOTH ME WATER MAIN AND ME SEWER SHALL BE
CONSTRUCTED OF FERROUS MAMRWS AND WITH JOINTS EQUIVALENT TO
WATER MAIN STANDARDS FOR A DISTANCE BE
10, ON EACH SIDE OF ME
PONT OF CROSSING. A FOR
OF WATER MAJN PIPE SIWL BE
CENTERED AT ME POINT OF CROSSING.
C 10. ALL CONCREE SHALL RE 3.0W PS STRENGTH (M MY), UNLESS OTHERWISE
NOTED.
11. CONTRACTOR SHALL COSTAL APPROVED WARNING TAPE OVER PIPE CENTERS AT
A DEPTH OF 13' TO 2'.
12. CONIBICTOR SNAIL WIKAN TEMPORARY POWER TO ALL EXSTING BUILDINGS AS
MOUIRED WRING CONSTRUCTION.
13. CONTRACTOR SHALL CONTICT HIDE CWNTY WATER DEPARTMENT AT
252-926-4196 TO COORDINATE NEW WATER SERVICE
B
A
Z 3
TO]-OGRAPICAL SURNtEY NOi �
1. SURVEY BY DEWERRY k DAMS. INC. OARED MAY 5. 2009.
2. HORIZONTAL CONTROL IS RELATED TO POINT NUMBER 1 AND POINT NUMBER 2.
POINT NUMBER I 14=631266a2 E=26a0N25.58
POINT NUMBER 2 N=631201.I6 E-22860a95.50
POINT NUMBER 1 IS 85.6NORTHEASTERLY OF A SANITARY SEWER MANHOLE AND
85.2' NORTHWESTERLY W A HYDRANT.
PONT NUMBER 2 IS A NAIL 116' SWTHERLY OF A CONCRETE BRIDGE, 20.3' WESTERLY
OF ME EDGE OF ASPHALT AND 52.7' NORTHWESTERLY OF A FENCE CORNER.
3. VERTICAL CONTROL IS RELATED TO PONT NUMBER 1 ELEVATION = 3,51 AND PONT
2 ELEVATON = 2.35. BENCHMARK IS A RAILROAD SPIKE IN A POWER POLE 112'
SWMEASTERLY OF ME PUMP STATION AND ALL WESTERLY OF MAINTENANCE BUILDING
ELEVATION - 5.87' (VALUES ARE NAM) 88)
a. VALUES OBTAINED BY UPS OPUS COSENIXM6 S. STATE PLANE COMDIRIATES SHOWN
ARE ON NORTH AMERICAN DATUM 1983 (NAG 83) AND THE VERTICAL TLEVAPONS
SHOWN ARE BASED ON NORTH AMERICAN KRICAL DATUM 1988 (NAY) 88)
5, ME SITE IS LOCATED WTHIN'ZONE AE" AS SHOWN ON FL000 INSURANCE RAM MAP (FIRM)
PANEL NUMBER '8542 J', MAP NUMBER 3720864200J EFFECTIVE DATE MAY 15. 2003
6, ME UNOERORWND UPLIFTS SHOWN HAVE BEEN LOCATED FROM REDO SURVEY
INFORMATION. THE SURVEYOR/ENCWEER MAKES NO GUARANTEE THAT ME UNDERGROUND
UTILITIES SHOWN COMPRISE ALL SUCH UTIUTES IN ME AREA. OTHER IN SER'MCE
0R ABANDONED, THE SURVEYOR/ENCINEER FIRMER DOES NOT WARRANT THAT ME
UNDERGROUND UTILMES SHOWN ARE IN ME EXACT LOCATION INDICATED.
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MM MCHME RAL DRAWINGS.
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Swan Quarter, INC 27885 y 9 g ry

I

•
Appendix B
Letters/Emails
Geotechnical Report
1i Supplementary Information
Stormwater Management Permit
Application Form
Operation and Maintenance Form
Express Permitting Form

Memorandum
Subject: LAKE MATTAMUSKEET - STORMWATER PERMITTING
Reviewer: Michael Hanson
Attendees: Chris Brown, Matt West, Eric Thomas
Date: 6/ 1 /09
The following summarizes my findings from discussions with NCDENR DWQ and
USACE regarding required stormwater permitting and design for this site.
Assumptions:
1. Site area approx 4 acres
2. Existing Impervious 60,000 sf
3. Proposed new impervious 100,000 sf
4. Existing site is approx 35% imp. Therefore site is High Density
5. No wetlands are located on site per DWQ and ACE
6. Tar -Pam buffers do not apply to redevelopment of existing impervious area
7. Tar -Pam buffers do apply to all existing pervious area
Express Permitting Process
1. Express permitting requires pre -application meeting
2. Can include DWQ, CAMA, E&SC
3. Fees are dependent on which agencies are involved.
4. DWQ fee for High Density is $4000 (this can cover all agencies except $65/acre
is required as a separate check for E&SC) @ 30 days
5. Normal fee is
a. CAMA $250-$475 @ 75-150 days
b. DWQ $505 @ 60-90 days
c. E&SC $250/acre @ 30 days
CAMA
1. Greater than 10,000 sf built upon area in Coastal Zone - CAMA Major permit is
required
2. Jurisdiction may not apply - pending review of letter
E&SC
1. Disturbed area is >1 ac - permit is required
DWQ State Stormwater
1. Disturbed area is >1 ac, High Density site - State Stormwater is required
2. Treatment based on 1.5 inches runoff or pre Q = post Q
3. Must treat 100% of added impervious area
4. Focus on routing all new impervious to the BMP
5. Can provide compensatory treatment, up to a 2:1 ratio may apply
6. No new outfalls to canals (except BMP with > 30% N treatment)
7. BMP must meet 85% removal per DENR Manual
8. High Density sites require soils testing
DWQ Wetlands and Buffers
10 1. No jurisdictional wetlands on site per letter —awaiting confirmation letter
tll Dewberry'

Memorandum
• 2. Tar -Pam buffers do not apply to redevelopment of existing impervious area —
change of use within buffer may require Impact Allowance Letter (can be
provided as part of Express Review)
3. Tar -Pam buffers do apply to all existing pervious area — adding new impervious
within Zone 1 Buffer if area is currently vegetated requires submittal of letter
requesting Variance.
0
0
ACE
1. No jurisdictional wetlands on site per letter
Dewberry"

West, Matthew
0
rom: Pullinger, Chris [[e-mail])
ant: Friday, November 06, 2009 8:39 AM
o: West, Matthew
Subject: RE: USFWS-Lake Mattmuskeet-Temporary Buffer Disturbance
Matt,
In this case, b/c the pump station is already there, and the impacts will be temporary and are of such a small scale, I'm
considering the structures as existing, and therefore the new disturbance would be considered exempt, and no
mitigation will be required, b/c the area will be restored/returned to grass after the temporary impacts are complete.
Therefore, no PCN will be required, but if you'd like to include this e-mail as a form of explanation for why the impacts
are exempt (because I'm considering them as an existing use)j, that probably would help and is OK with me.
- Chris
E-mail correspondence to and from this address may be subject to the
North Carolina Public Records Law and may be disclosed to third parties.
Chris Pullinger
Environmental Specialist
NC Division of Water Quality
irface Water Protection Section
ashington Regional Office
www.ncwaterguality.org
252.948.3920
As of April 2009, my new e-mail address is: chris.pullinger(@ncdenr.Rov
From: West, Matthew [ma iIto: [e-mail]]
Sent: Tuesday, November 03, 2009 9:59 AM
To: Pullinger, Chris
Subject: USFWS-Lake Mattmuskeet-Temporary Buffer Disturbance
Chris —
Hope you are doing well. We spoke last week concerning the temporary buffer disturbance associated with the new
Office/Visitor Center at Lake Mattamuskeet. You mentioned that since the area being disturbed is currently grass,
mitigation would likely not be required. We also discussed that a maintenance easement should exist as the pump station
the sewer line will connect to is existing. Can you please confirm whether the temporary buffer disturbance with be
considered exempt or allowed under the Tar Pamlico buffer rules? It is my understanding that if the temporary buffer
disturbance is exempt a PCN is not required. If the temporary buffer disturbance is allowed a PCN is required. Can you
please confirm if this is correct?
hanks,
att
Matthew B. West, PE, LEED® AP
Project Engineer
Dewberry

• Record of Communication
USFWS-Mattamuskeet National Wildlife Refuge
Conversation between Chris Pullinger, NCDWQ and Matt West, Dewberry
February 24, 2010 at 2:00 pm
•
r 1
U
Chris Pullinger and Matt West discussed the applicability of the Tar -Pamlico Buffer Rules to the
canals bounding the site on the south and west. Based on field delineations it has been
determined that these canals arc jurisdictional waters. Chris stated that even though the canals arc
jurisdictional the Tar -Pamlico Buffer Rules do not apply based on 15 NCAC 02B .0259 (3)(a)(i).
This item states that an exemption can be granted based on the following:
"Ditches and manmade conveyances other than modified natural streams unless
constructed for navigation or boat access."
The following letter prepared by Chris dated May 13, 2009 is still valid and states the buffers do
not apply to these canals.
0 nemrbe>r"O

•
11
NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Coleen H. Sullins Dee Freeman
Governor Director Secretary
May 13, 2009
Mr. Bruce Freske
38 Mattamuskeet Road
Swan Quarter, NC 27885
DWQ Project # 2009-0496
Hyde County
Subject Property: Lake Mattamuskeet NWR Ranger Station Improvements
UT to Outfall Canal, Tar -Pamlico River Basin
On -Site Determination for Applicability to the Tar -Pamlico River Riparian Area
Protection Rules (15A NCAC 2B .0259)
Dear Mr. Freske:
At your request I conducted an on -site determination to review a drainage feature located
on the subject property for applicability to the Tar -Pamlico Buffer Rules (15A NCAC 2B
.0259). The feature is labeled as "2009-0496" on the attached map initialed by me on
May 13, 2009. The project is located on the west side of SR 1330 (Outfall Canal Road),
approximately 0.7 miles north of the intersection of SR 1330 and US HWY 264, north of the
community of New Holland, NC.
The Division of Water Quality (DWQ) has determined that the surface waters
highlighted in blue and labeled as "2009-0496" on the attached map are Subiect to
the Tar -Pamlico Buffer Rule. However, the proposed project/activity to rebuild
structures in the previously disturbed footprint is Exempt. The portions of the surface
waters highlighted in pink, along with any existing drainage features not shown on the
attached map are Exempt from this rule. This feature and its associated buffers should
be identified on any future plans for this property. The owner (or future owners) should
notify the DWQ (and other relevant agencies) of this decision in any future
correspondences concerning this property. This on -site determination shall expire five
(5) years from the date of this letter.
Landowners or affected parties that dispute a determination made by the DWQ or
Delegated Local Authority that a surface water exists and that it is subject to the buffer
North Carolina Division of Water Quality Internet: www.ncwwcrouality.ore
943 Washington Square Mall Phone: [phone] One
Washington, NC27889 I7AX 252-946-9215 North Ca/+rolliinat
An Equal Opportunity/Affirmative Action Employer— 50%Recycledll0% Post Consumer Paper Naturally

Page 2 of 2
rule may request a determination by the Director. A request for a determination by the
Director shall be referred to the Director in writing c/o Cyndi Karoly, DWQ, 401
Oversight/Express Review Permitting Unit; 2321 Crabtree Blvd., Suite 250, Raleigh, NC
27604-2260. Individuals that dispute a determination by the DWQ or Delegated Local
Authority that "exempts' a surface water from the buffer rule may ask for an adjudicatory
hearing. You must act within 60 days of the date that you receive this letter. Applicants
are hereby notified that the 60-day statutory appeal time does not start until the affected
party (including downstream and adjacent landowners) is notified of this decision. DWQ
recommends that the applicant conduct this notification in order to be certain that third
party appeals are made in a timely manner. To ask for a hearing, send a written petition,
which conforms to Chapter 150B of the North Carolina General Statutes to the Office of
Administrative Hearings, 6714 Mail Service Center, Raleigh, N.C. 27699-6714. This
determination is final and binding unless you ask for a hearing within 60 days.
_ This letter only addresses the applicabJity_to-the_huffersules_and-does not_approve.any -
activity within the buffers. Nor does this letter approve any activity within Waters of the
United States or Waters of the State. If you have any additional questions or require
additional information please call Chris Pullinger at [phone].
Sincerely,
(.L�-, L
Chris Pullinger
Enclosures: copy of New Holland quadrangle, 1:24,000 USGS topographic map
cc: DWQ 401 Oversight/Express Unit
Troy A. Shelton, Dewberry & Davis Inc., 551 Piney Forest Road, Danville, VA 24540
U.S. Army Corps of Engineers - Washington Field Office, Tom Steffens
WaRO File Copy
Filename: 2009-0496

worffi Carofins Environmental
Mw-opmehi-Commission
Of Water Quality
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West, Matthew
om: Trowell, Steve [[e-mail])
nt: Friday, June 05, 2009 3:35 PM
o: Hanson, Michael
Subject: RE: Lk Mattamuskeet Visitor Center
Mr. Hansons:
Based on the pdf file you sent me replacement of the Maintenance Garage and Ranger Station at Lake Mattamuskeet
Wildlife Refuge off SR 1330 in Hyde County at New Holland, North Carolina will not take a permit nor any project review
from this Division as the construction will take place outside any Area of Environmental Concern (AEC) under the
jurisdiction of this Division. If you need further clarification please let me know.
Steve Trowell
Division of Coastal Management
Coastal Management Representative
943 Washington Sq Mall
Washington, NC 27889
252-948-3854 - Office
252-948-0478 - Fax
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be
disclosed to third parties.
•
From: Hanson, Michael [maiIto: [e-mail]]
Sent: Monday, June 01, 2009 3:00 PM
To: Trowell, Steve
Cc: [e-mail]; West, Matthew
Subject: Lk Mattamuskeet Visitor Center
Mr. Trowell, we recently contacted Mr. David Moy of your office to confirm the applicability of CAMA regulations to our
project site. We are designing the replacement of the Maintenance Garage and Ranger Office at the Lake Mattamuskeet
Wildlife Refuge. In our discussions Mr. Moy indicated that he did not think CAMA applied to this area because it was
outside of a 75 ft zone around the Outfall Canal from the lake. He directed us to submit a figure showing the actual
location of the project and request that you provide us an official determination of whether or not CAMA regulations
would apply to this site.
Please feel free to contact us with any questions you may have. We look forward to hearing from you.
Michael A. Hanson, PE
Dewberry & Davis, Inc.
2301 Rexwoods Or
Suite 200
sleigh, NC 27607
one:919-881-9939
Cell: 919-637-5594

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Name: NEW HOLLAND Location: 035° 27' 08.89" N 076° 10' 38.38" W
Date: 6/1 /2009
Scale: 1 inch equals 1000 feet

�c4.J
•
•
ECS CAROLINAS, LLP "Setting the Standard for Service"
Geotechnical • Construction Materials • Environmental • Facilities
June 12, 2009
Mr. Matthew West, P.E.
Dewberry.
2301 Rexwoods Drive, Ste. 200
Raleigh, North Carolina 27607
Reference: Report of Seasonal High Water Table Estimation
Lake Mattamuskeet Wildlife Refuge
Lake Landing, Hyde County, North Carolina
ECS Project No. 22.15009
Dear Mr. West,
ECS Carolinas, LLP (ECS) recently conducted an estimation of the Seasonal High Water Table
(SHWT) for the proposed stormwater best management practice (BMP) areas at the Lake
Mattamuskeet Wildlife Refuge site in Lake Landing, Hyde County, North Carolina. This letter,
with attachments, is the report of our estimation.
Field Testing
On June 11, 2009, ECS conducted an exploration of the subsurface soil and groundwater
conditions at three requested locations shown on the attached Boring Location Plan (Figure 1).
The purpose of this exploration was to obtain subsurface information of the suitability of the in -
place soils for the proposed stormwater BMP areas. The borings were located utilizing GPS.
equipment. ECS explored the subsurface soil and groundwater conditions by advancing one
hand auger boring into the existing ground surface at the requested boring locations. ECS
Visually classified the subsurface soils and obtained representative samples of each soil type
encountered. ECS recorded the SHWT and groundwater level observed at the time of each
hand auger boring. The attached SHWT sheet provides a summary of the subsurface
conditions encountered at each hand auger boring location.
The groundwater level and the SHWT were estimated at each boring location below the existing
grade elevation. Below is a summary of each boring location.
Location
Water Level
SHWT
1
36 inches
6 inches
2
Winches
0 inches
3
30 inches
0 inches
The SHWT may vary within the proposed site due to changes in subsurface conditions and
elevation.
7211 Ogden Business Park, Suite 201, Wilmington, NC 28411 • T: 910-686-9114 F: 910-686-9666 www.ecslimited.com
ECS Carolinas, LLP • ECS Florida, LLC • ECS Illinois, LLC • ECS Mid -Atlantic, LLC • ECS Southeast, LLC ' ECS Texas, LLP

Report of SHWT Estimation
Lake Mattamuskeet Wildlife Refuge
• Lake Landing, Hyde County, North Carolina
ECS Project No. 22.15009
June 12, 2009
Closure
The activities and evaluative approaches used in this assessment are consistent with those
normally employed in assessments of this type. Our evaluation of site conditions has been based
on our understanding of the project information and the data obtained during our field activities.
ECS appreciates the opportunity to provide our services to you on this project. If you have any
questions concerning this report or this project, please contact us at [phone].
Respectfully,
ECS CAROLINAS, LLP
K. Brooks Wall
Project Manager
Attachments: Boring Location Plan
SHWT sheet
•
0
John . Lair, P.G.
Pd ipal Geologist

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Lake Mattamuskeet Wildlife Refuge
Lake Landing, Hyde Co., NC
ECS Project No. 22-15009
June 11, 2009
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BORING LOCATIONS
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Figure 1— Test Location Plan
Provided by: Dewberrry

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1]
Season High Water Table Estimation
Lake Mattamuskeet Wildlife Refuge
Lake Landing, Hyde County, North Carolina
ECS Project No. 22.15009
June 11, 2009
Location Depth
1 0-24"
24"-36"
36"-48"
Soil Description
Dark gray silty SAND (fill)
Black SILT w/sand
Gray fine SAND w/silt
Seasonal High Water Table was estimated to be at 6 inches below the
existing grade elevation.
Groundwater was encountered at 36 inches below the existing grade
elevation.
Location Depth Soil Description
2 0-18" Gray/orange silty SAND
18"-24" Black SILT w/sand
24"-36" Gray fine SAND w/silt
Seasonal High Water Table was estimated to be at 0 inches below the
existing grade elevation.
Groundwater was encountered at 30 inches below the existing grade
elevation.
Location Depth Soil Description
3 0-18" Gray/orange silty SAND
18"-24" Black SILT w/sand
24"-36" Gray fine SAND w/silt
Seasonal High Water Table was estimated to be at 0 inches below the
existing grade elevation.
Groundwater was encountered at 30 inches below the existing grade

Mattamuskeet National Wildlife Refuge Office/Visitor Station and Out -Buildings
Stormwater Permitting
Supplementary Information
General Infonnation
a. Name of Project: Mattamuskeet National Wildlife Refuge Office/Visitor
Station and Out -Buildings
b. Street Address, City, County: 38 Mattamuskeet Road, Swan Quarter, NC
27885
c. Acres in Tract: 50,180 acres
d. Acres Being Disturbed: 5 acres
e. Acres in Wetlands: NA
Wetlands Must Be Delineated & Sign -Off Obtained From The Corps
2. Proposed Wetland Impacts Require Permits From Corps & DWQ
f. Ownership Information From NC Secretary of State Web Site: US
Department of the Interior (US Fish and Wildlife Service)
g. Description of Development Proposal
I. Previous or Existing Permits. NA
2. Tax parcel ID Number:
h. Pre-1988 Built Upon Area, If Applicable: NA
i. Discuss Phasing of the Project & Stormwater Facilities When Applicable
j. Discuss Proposed Waste Water Treatment & Water Supply: NA
k. Identify Historic Sites & Projects Being Funded With Public Monies: NA
I. Disclose Any/All Non -Compliance Issues with DENR Agencies: NA
2. Stormwater Information
a. Provide River Basin, Stream Classification & Index Number for All water
Bodies On or Adjacent To The Project or Closest to The Project Area
Outfall Canal- Classification SC (Class SC
All tidal salt waters protected for secondary recreation such as fishing,
boating, and other activities involving minimal skin contact; fish and
noncommercial shellfish consumption; aquatic life propagation and
survival; and wildlife)
Tar Pamlico River Basin,
Outfall Canal and Lake Mattamuskeet
Classification SC
Index Number— 29-51-1 and 29-57-1-1
0_._a__ .....a_ E=:—
Sap
.,ak- Ma..az'a,._e-. 2nn:ie
b. Identify Whether the Stormwater Design is High Density or Low Density,
® Commercial or Residential, State Stormwater or NPDES Phase 11, Address
Vested Rights When Applicable; Identify Pockets of High Density
High Density

• Institutional
State Storm water
e. Proposed Total % Impervious Surface
52%
d. Number of Proposed Treatment Measures, Type(s) of Collection System
One wet detention basin
e. Will All Built Upon Area Be Collected
No. Based on the discussion with the DWQ,
f. Identify Whether or Not the Project Has Buffer Requirements & Whether
or Not Development Is Proposed Within A Buffer
No the project do not have a buffer requirement.
g. Discuss Coastal Management Areas of Environmental Concern When
Applicable
NA
h. Disclose Whether or Not Off -Site Runoff Is Coming Onto The Site or Into
The Proposed BMP
NA
L Discuss Whether Road Construction Across Other property Is Necessary
To Access This Project
NA
If An On -Site Evaluation Of The Soils Has Been Done, Discuss
Infiltration Rates, Seasonal High Water Table, etc., and Include Date Of
Site Evaluation (This Is Required For Infiltration Projects).
Yes, onsite soil evaluation was performed and the geotechnical report is
included in the submittal.
0

�i
19
Appendix
Discharge Calculations Spreadsheet
Chain Saw Routing Spreadsheet
Supplement_WetBasin_Rev.8 Spreadsheet

® POINT PRECIPITATION
North Carolina 35.45 N 76.177 W 0 feet
• ��� FREQUENCY ESTIMATES
from 'Precipitation -Frequency Atlas of the United States" NOAA Atlas 14, Volume 2, Version 3
FROM NOAA ATLAS 14
G.M. Bonnin, D. Martin, B. Lin, T. Parrybok, M.Yekta, and D. Riley
NOAA, National Weather Service, Silver Spring, Maryland, 2004
Extracted: Mon Aug 10 2009
E
0
Precipitation I ensitv Estimates iNhr
ARI'
5 min
15 min
30 min
60 min
120 min
3 hr
6 hr
12 hr
24 hr
48 hr
4-day-
7 day
10 day
20 day
30 day
45 day
60 day
(years)
1
5.68
3.78
2.59
1.62
0.96
0.69
0.42
0.25
0.15
0.08
0.05
0.03
0.02
0.02
0.01
0.01
0.01
2
6.41
4.29
2.96
1.86
1.11
0.8
0.48
0.28
0.18
0.1
0.06
0.04
0.03
0.02
0.02
0.01
0.01
5
6.88
4.65
3.3
2.12
1.28
0.93
0.56
0.33
0.23
0.13
0.07
0.05
0.04
0.02
0.02
0.02
0.01
10
8.2
5.53
4.01
2.61
1.61
1.17
0.71
0.42
0.27
0.16
0.09
0.06
0.04
0.03
0.02
0.02
0.02
25
9.19
6.19
4.581
3.05
1.93
1.411
0.86
0.511
0.34
0.191
0.1
0.071
0.05
0.03
0.031
0.02
0.02
50
10.31
6.92
5.21
3.53
2.28
1.69
1.03
0.62
0.39
0.23
0.12
0.08
0.06
0.04
0.03
0.02
0.02
too
11.17
7.48
5.73
3.94
2.59
1.94
1.19
0.72
0.45
0.26
0.14
0.09
0.07
0.04
0.03
0.03
0.02
200
12.04
8.02
6.24
4.38
2.93
2.22
1.37
0.83
0.52
0.3
0.16
0.1
0.07
0.05
0.04
0.03
0.02
500
12.94
8.59
6.83
4.9
3.35
2.57
1.59
0.97
0.62
0.36
0.18
0.11
0.09
0.05
0.04
0.03
0.03
1000
14.05
9.26
7.49
5.47
3.81
2.97
1.84
1.14
0.7
0.41
0.21
0.13
0.09
0.06
0.04
0.04
0.03
Precipitation Frequency Estimates (inches)
ARI•
5 min
15 min
30 min
60 min
120 min
3 hr
6 hr
12 hr
24 hr
48 hr
4 da
7 day
10 day
20 day
30 da
45 day
60 da
(years)
1
0.47
0.94
1.3
1.62
1.92
2.08
2.51
2.95
3.49
4.03
4.55
5.29
5.97
8.03
9.92
12.24
14.67
2
0.53
1.07
1.48
1.86
2.22
2.4
2.9
3.42
4.25
4.88
5.51
6.38
7.16
9.57
11.8
14.49
17.3
5
0.57
1.16
1.65
2.12
2.57
2.78
3.37
3.98
5.49
6.27
7.01
8.02
8.86
11.63
14.19
17.33
20.45
10
0.68
1.38
2
2.61
3.23
3.52
4.26
5.06
6.53
7.46
8.25
9.37
10.27
13.34
16.11
19.67
22.96
25
0.77
1.55
2.291
3.05
3.85
4.241
5.15
6.161
8.06
9.251
10.06
11.311
12.3
15.73
18.751
22.95
26.4
50
0.86
1.73
2.61
3.53
4.56
5.07
6.18
7.44
9.4
10.8
11.57
12.93
13.98
17.7
20.87
25.61
29.14
100
0.93
1.87
2.86
3.94
5.18
5.84
7.13
8.65
10.86
12.54
13.23
14.66
15.77
19.77
23.02
28.41
31.89
200
1
2
3.12
4.38
5.86
6.67
8.18
9.98
12.47
14.48
15.02
16.53
17.68
21.94
25.23
31.31
34.7
500
1.08
2.15
3.42
4.9
6.69
7.72
9.51
11.7
14.87
17.39
17.69
19.21
20.42
25.02
28.27
35.36
38.49
1000
1.17
2.31
3.75
5.47
7.61
8.91
11.04
13.69
16.91
19.91
20.15
21.47
22.67
27.49
30.65
38.6
41.42

•
•
Mattamuskeet National Wildlife Refuge Office/Visitor Station and Out -Buildings
Total Impervious Area Change Due to Re -Development of the Site
Treatment Volume based on pre and post impervious
area
Proposed Impervious Area
105,852
ft2
Exisitng Impervious Area
71,263
ft2
Difference in Impervious Area
34,588
ft2
Required Treatment Volume Coastal, 1.5 in.
4,324
ft3

•
•
•
Mattamuskeet National Wildlife Refuge ONiceAlisitor Station and Out -Buildings
Wet Detention Basin
Area contributing_.___to BMP pre -post Q (Basin 62)_'__
�. ��_____ _
Pre-develo ment conditions to Basin
Rational C Area ac CN
Pervious Managed Open Space) 0.15 0.16 li 80
Impervious 8 Open Water 1 0.9 0.20 1 98
Woods 1 0.15 0.60 1 79
Composite
C:
0.31
Total Area
0.96
Composite C:
0.90
Total Area
0.96
ac
Composite CN -
98.0
Tc
5
min
BMP Design for 90 % TSS Removal
i
Water Quality Volume controls treatment
Pre -development 1- r, 24-hr runoff
2,124
Post -development 1- r, 24-hr runo
6,243
Estimated Storage Required (1 rza
4,119
fta
0.09 acre-ft
BMP Selected
Extended Detention
Wetland
%impervious
100%
'SA/DA ratio - 90 % TSS Removal
for 3.5 ff depth)
10.00
Drainage Area ac
0.96
Required Surface Area (Perm
Pool
0.10
ac
4,182
sf
Rv runoff coeff)
0.95
Basin 82 Volume (1.5" storm)
0.11
ac-ft
4,966
cf
Volume Required for increased
impervious overall site
4,324
cf
Water Quality provided for Basin 82
controls

•
•
0
nkeel N.nional \Vild6rr Reruee oRadeision Shown and out-Buildinas
Elevations, Areas, Incremental Volumes 8 ACumulated Volumes for Overall Pond and Forebay
BMW Permanent Pool for 85%TSS
Removal
SHWL EI. Soils Period)
14
Sediment Depth
I 0
Sediment Cleanout In
-4.1
Pond Bottom El.
.3.1
Bottom shelf EI.
0 4
Permanent Pool El.
09
Est Tern,mr, Pool El.
162
Depth
3 5
Am w
5 476
A.
669
6 913
PP Average Deth
3.1
SNDA Ratio'
0.2%
Min PP No. (aff
3429
add 10.2 (Coastal, use day=3(
SHW proviold 21
ECS Geotech Re rt 14
Groundwater Analysis
Seasonal High Water El 1 1.4
Est, Seasonal Low Water El, 040
Permanent Pool elevation 090
Forebay Vel, 3,728
Percent of PP 21%
WI Fareba
Purllmina Pond Dlmenslona
Length
Width
Adj.
Fambay L
Foreba W
I Forebay A
Square Area
Dval area
Elev,
St.,
135
90
0
0
0
1 0
12t50
9538
24
3
132
87
a
0
0
0
11484
W15
1 9
3
129
84
0
0
0
0
10836
85W
14
10
119
74
0
72
27
1944
8806
6913
0.9
to
109
64
0
70
25
1750
6976
5476
04
2
107
62
0
68
23
1564
6634
5208
-0.1
2
105
60
0
66
21
13W
63W
4946
-06
2
103
58
0
64
19
1216
5974
4690
-1.1
2
101
56
0
62
17
1054
56M
4440
-16
2
99
54
a
60
15
9W
SUB
4197
-2.1
2
97
52
a
58
13
754
5044
39W
-26
2
95
50
0
0
0
0
4750
3729
-3.1
2
93
10
a
0
0
44W
3504
-06
2
91
46
0
0
0
0
418fi
32Bfi
-4.1
2
89
49
0
0
0
0
3916
3014
-4.6
2
87
42
0
0
0
1 0
3654
2868
-5.1
2
85
1 40
1 0
0
0
1 0
34W
26fi9
5.5
2
'Assumes Forebay is RatlafmArall Pond area. Use Pond area for S DA calculations and incorporate lorebay during pond layout.
Temporary Pool
To, of IM Vegetaud shell/ SHIVA.
Permanent Pool
Bottom of 100 Vegetated shelf/
Sediment Cleafwm Topl Pond Bonom
Sediment Cleanout Bottom,
ACNal Graded Areas from CADD
Actual Forrest,
Areas
from CADD
A.
Elay.
Ina. Vol.
Total Vol.
Area
Ele,
Inc. Vol,
Total Vol.
8007
1.9
3879
26,511
2836
1.9
1361
7802
2559
1.45
3]]
19235
2.02
145
131
5161
7W9
14
3398
22632
2609
14
1280
6441
6082
0.9
2734
10858
2509
09
1,145
5030
4852
04
2357
16,125
2070
04
982
3086
4574
-0.1
2220
13.768
1859
-0.1
741
2W3
4304
-06
2087
11549
1105
-06
516
2162
4044
-1.1
1959
9.462
958
-1.1
444
1617
]]90
-16
1584
7503
81]
-16
375
1203
2544
.2.1
1463
5,920
683
-2.1
310
828
3307
26
1,59]
4,457
555
-26
248
518
3079
-31
1484
2060
435
-3.1
1W
271
2858
36
1376
1,3➢6
324
-36
01
BI
2 646
-d.1
0
0
4 1
0
0
demand area Camlw Wl,
t o,843 34,313
10,191 24,3%
10.118 29,073
e,591 23,000
6.922 2o,o10
6,433 16671
5409 13,711
S,W2 11, 1"
4.607 8,I06
3,227 6,747
3,862 4.975
3,514 3,131
3,182 1,457
2.646 -

L A
L_J
iNattmnuskeet National
Wildlife Refuge Office/Visitor Station and Out -Buildings
Wet Detention Basin
S
Contour
Area
Accum
Z
CHECK
CHECK SA
Contour
(ft2)
Incr Vol (ft3)
Vol (ft3)
Stage (ft)
In(S)
In(Z)
Z est
0.4
6922
0
0
0.9
8591
3878
3,878
0.5
8.26
-0.69
0.50
8,928
1.4
10118
4677
8,556
1
9.05
0.00
0.99
9,931
1.9
10843
5240
13,796
1.5
9.53
0.41
1.51
10,569
2.4
11600
5611
19,407
2
9.87
0.69
2.02
11,046
WQ Volume 1.5"
ravided 5.186
ft3
Elevation for WO Volume 1 1.451
ft
Estimate Vol for 1
yr24hrAttentuation
4,119 ft3
Elevation for Attenuation Volume
1.43 1 ft
xcoeff I
1.1536 b =
1.15
interce t 1
9.0605 1 Ks =
8608
y = 1.1536x + 9.0605
9:40-}
9.20
-8:80
8:60
8:40
820
-0.80
-0.60 -0.40
-0.20 0.00 0.20
0.40
0.60
•
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