20180121 Ver 2_Stormwater OI_20190321

TOWN OF OAK ISLAND
PUBLIC WORKS DEPARTMENT
STORMWATER PERMIT
High Density Development
In accordance with the provisions of the Phase II Stormwater Ordinance (Ch. 18, Art. V)
PERMISSION IS HEREBY GRANTED TO
Pine Forest Development Company, LLC
R. Thomas Sofield, Manager
355 Industrial Park Drive
Boone, NC 28607
Hawthorne at Pine Forest
Oak Island, NC
FOR THE
Construction, operation and maintenance of a wet detention basin and all components and
features of the stormwater collection system within the project boundaries, all hereinafter known
as the Stormwater System, in compliance with the provisions of the stormwater ordinance and
the approved stormwater management plan and specifications and other supporting data as
attached and on file with and approved by the Town of Oak Island Stormwater Administrator
and considered part of this permit.
This permit shall be effective from the date of issuance until rescinded and shall be subject to the
conditions and limitations:
I. DESIGN STANDARDS
1. This permit is effective only with respect to the nature and volume of stormwater
described in the application and other supporting data.
2. This stormwater system has been approved for the management of stormwater
runoff as described in the application documents and as shown on the approved
plans.
3. The tract will be limited to the amount of built -upon area indicated on the
approved plans.
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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.
5. The runoff from all built -upon area within the permitted drainage area of this
project must be directed into the permitted Stormwater System.
6. The built -upon areas associated with this project shall be located at least 50 feet
landward of all perennial and intermittent surface waters.
7. The design criteria provided in the approved plans must be maintained.
II. SCHEDULE OF COMPLIANCE
1. During construction, erosion shall be kept to a minimum and any eroded areas of
the system will be repaired immediately.
2. The permittee shall at all times provide the operation and maintenance necessary
to assure the permitted Stormwater System functions at optimum efficiency. The
specific Operation and Maintenance Agreements for the wet detention basin must
be followed in its entirety. Maintenance of the stormwater collection system
includes, but isnot limited to:
a. Scheduled inspections.
b. Sediment removal.
c. Mowing and re -vegetation of slopes.
d. Immediate repair of eroded areas.
e. Maintenance of all slopes in accordance with approved plans.
f. Debris removal and unclogging of all drainage structures,
underdrains, catch basins and piping.
Records of maintenance activities must be kept and made available upon request
to authorized personnel. The records will indicate the date, activity, name of
person performing the work and what actions were taken. The person responsible
for maintenance of any structural BMP installed shall submit to the Stormwater
Administrator an inspection report from one of the following persons performing
services only in their area of competence: a qualified registered North Carolina
professional engineer, surveyor, landscape architect, soil scientist, aquatic
biologist, or person certified by the North Carolina Cooperative Extension Service
for stormwater treatment practice inspection and maintenance. All inspection
reports shall be on forms approved by the Stormwater Administrator. An original
inspection report shall be provided to the Stormwater Administrator beginning
one year from the date of as -built certification and each year thereafter on or
before the date of the as -built certification.
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3. 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
supporting data.
4. 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.
5. 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.
6. The permittee shall submit to the Stormwater Administrator 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
e. Further subdivision, acquisition, lease or sale of all or part of the
project area.
f. Filling in, altering, or piping of any vegetative conveyance shown
on the approved plan.
7. Upon completion of a project, and before a certificate of occupancy is granted,
the applicant shall certify that the completed project is in accordance with the
approved stormwater management plans and designs, and shall submit actual "as -
built" plans. The plans shall show the final design specifications for all
stormwater management facilities and practices and the field location, size, depth,
and planted vegetation of all measures, controls, and devices, as installed. The
designer of the stormwater management measures and plans shall certify, under
seal, that the as -built stormwater measures, controls, and devices are in
compliance with the approved stormwater management plans and designs and
with the requirements of the Stormwater Ordinance.
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III. GENERAL CONDITIONS
1. This permit is not transferable except after notice to and approval by the Town of
Oak Island Stormwater Administrator.
2. 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 governmental agencies (local, state, federal) having jurisdiction.
3. 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 the Town, such as the construction of
additional or replacement stormwater management systems.
4. Approved plans and specifications for this project are incorporated by reference
and are enforceable parts of the permit.
5. The permittee shall notify the Town Stormwater Administrator any name,
ownership or mailing address changes within 30 days.
441
Permit issued this the day of December, 2018.
TOWN OF OAK ISLAND
— 6 z1v
Gene kudgus,Sto
, water Administrator
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Appendices
Appendix A. Wet Detention Basin Operation and Maintenance Agreement
Appendix B. Designers Certification
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APPENDIX A
Page 6 of 12

Permit Number:
(to be provided by DWQ)
Drainage Area Number:
Wet Detention Basin Operation and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
The wet detention basin system is defined as the wet detention basin,
pretreatment including forebays and the vegetated filter if one is provided.
This system (check one):
❑ does ® does not incorporate a vegetated filter at the outlet.
This system (check one):
❑ does ® does not incorporate pretreatment other than a forebay.
Important maintenance procedures:
— Immediately after the wet detention basin is established, the plants on the
vegetated shelf and perimeter of the basin should be watered twice weekly if
needed, until the plants become established (commonly six weeks).
— No portion of the wet detention pond should be fertilized after the first initial
fertilization that is required to establish the plants on the vegetated shelf.
— Stable groundcover should be maintained in the drainage area to reduce the
sediment load to the wet detention basin.
— If the basin must be drained for an emergency or to perform maintenance, the
flushing of sediment through the emergency drain should be minimized to the
maximum extent practical.
— Once a year, a dam safety expert should inspect the embankment.
After the wet detention pond is established, it should be inspected once a month and
within 24 hours after every storm event greater than 1.0 inches (or 1.5 inches if in a
Coastal County). Records of operation and maintenance should be kept in a known set
location and must be available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element:
Potentialproblem:
How I will remediate theproblem:
The entire BMP
Trash/debris is present.
Remove the trash/debris.
The perimeter of the wet
Areas of bare soil and/or
Regrade the soil if necessary to
detention basin
erosive gullies have formed.
remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
Vegetation is too short or too
Maintain vegetation at a height of
long.
approximately six inches.
Form SW401-Wet Detention Basin O&M-Rev.4 Page 1 of 4

Permit Number:
(to be provided by DWQ)
Drainage Area Number:
BMP element:
Potentialproblem:
How I will remediate theproblem:
The inlet device: pipe or
The pipe is clogged.
Unclog the pipe. Dispose of the
swale
sediment off-site.
The pipe is cracked or
Replace the pipe.
otherwise damaged.
Erosion is occurring in the
Regrade the swale if necessary to
swale.
smooth it over and provide erosion
control devices such as reinforced
turf matting or riprap to avoid
future problems with erosion.
The forebay
Sediment has accumulated to
Search for the source of the
a depth greater than the
sediment and remedy the problem if
original design depth for
possible. Remove the sediment and
sediment storage.
dispose of it in a location where it
will not cause impacts to streams or
the BMP.
Erosion has occurred.
Provide additional erosion
protection such as reinforced turf
matting or riprap if needed to
prevent future erosion problems.
Weeds are present.
Remove the weeds, preferably by
hand. If pesticide is used, wipe it on
the plants rather than spraying.
The vegetated shelf
Best professional practices
Prune according to best professional
show that pruning is needed
practices
to maintain optimal plant
health.
Plants are dead, diseased or
Determine the source of the
dying.
problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application to establish the
ground cover if a soil test indicates
it is necessary.
Weeds are present.
Remove the weeds, preferably by
hand. If pesticide is used, wipe it on
the plants rather than spraying.
The main treatment area
Sediment has accumulated to
Search for the source of the
a depth greater than the
sediment and remedy the problem if
original design sediment
possible. Remove the sediment and
storage depth.
dispose of it in a location where it
will not cause impacts to streams or
the BMP.
Algal growth covers over
Consult a professional to remove
50% of the area.
and control the algal growth.
Cattails, phragmites or other
Remove the plants by wiping them
invasive plants cover 50% of
with pesticide (do not spray).
the basin surface.
Form SW401-Wet Detention Basin O&M-Rev.4 Page 2 of 4

Permit Number:
(to be provided by DWQ)
Drainage Area Number:
BMP element:
Potentialproblem:
How I will remediate theproblem:
The embankment
Shrubs have started to grow
Remove shrubs immediately.
on the embankment.
Evidence of muskrat or
Use traps to remove muskrats and
beaver activity is present.
consult a professional to remove
beavers.
A tree has started to grow on
Consult a dam safety specialist to
the embankment.
remove the tree.
An annual inspection by an
Make all needed repairs.
appropriate professional
shows that the embankment
needs repair. (if applicable)
The outlet device
Clogging has occurred.
Clean out the outlet device. Dispose
of the sediment off-site.
The outlet device is damaged
or replace the outlet device.
The receiving water
Erosion or other signs of
_Repair
Contact the local NC Division of
damage have occurred at the
Water Quality Regional Office, or
outlet.
the 401 Oversight Unit at 919-733-
1786.
The measuring device used to determine the sediment elevation shall be such
that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
When the permanent pool depth reads 7.0 feet in the main pond, the sediment
shall be removed.
When the permanent pool depth reads 7.0 feet in the forebay, the sediment
shall be removed.
Sediment Removal
Bottom
33 1 1
-----------------
FOREBAY
BASIN DIAGRAM
(fill in the blanks)
r -ft Min.
Sediment
Storage
Permanent Pool Elevation 40
Pool
------Sediment Removal -Elevation -33 ------------- Volumt
---
-----------
Bottom Elevation
MAIN POND
Form SW401-Wet Detention Basin O&M-Rev.4 Page 3 of 4
1 -ft
Storage

Permit Number:
(to be provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. I agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible party.
Project name:u
C -%
BMP drainage area number: :1
Print name:
Title: „ -Q'. -
a
Address:
Phone: ��M _ / .
Signature:
9
Date:
564''��r
Note: The legally responsible party should not be a homeowners association unless more than 50% of
the lots have been sold and a resident of the subdivision has been named the president.
I,- l , a Notary Public for the State of
, County of C,� , do hereby certify that
�- - c -VW , personally appeared before me this C
35
day of � ,2ica VE,, and acknowledge the due execution of the
forgoing wet detention basin maintenance requirements. Witness my hand and official
seal,
G. L s gy MARSH
C T ARY PUBLIC
WATAUCA CCUNT`�
STATE {fir NORTH CARROILINA
My commission expires_ ( .1 1 - ` -
Form SW401-Wet Detention Basin O&M-Rev.4 Page 4 of 4

Page 11 of 12

Town of Oak Island Stormwater Management
Pine Forest Development Company, LLC
Hawthorne at Pine Forest
Oak Island, NC
Designer's Certification
I, , as a duly registered
In the State of North Carolina, having been authorized to observe (periodically/weekly/full time)
the construction of the project,
Hawthorne at Pine Forest
(Project)
For
(Project Owner) hereby state that, to the best of
My abilities, due care and diligence was used in the observation of the project construction such that the
construction was observed to be built within substantial compliance and intent of the approved plans and
specifications.
Noted deviations from approved plans and specifications:
Signature
Registration Number
Date
Page 12 of 12
SEAL