SW1080104_Cover Letter & Permit_20080507

W A rF9
Michael F. Easley, Governor
March 21, 2008
Bo Caldwell
Henderson County Schools
414 Fourth Avenue
Hendersonville, North Carolina 28739-4216
Dear Mr. Caldwell:
William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
�, .,---------Colcen 11. S611ins Director
Division of Water Quality
l M AY - 7 2008
1NljF F,, C'-UALI T Y 5Ef�TIOH
(7rC. C_,�L O
Subject: Stormwater Permit No.: SW 1080104
Mills River Elementary School
Henderson County, North Carolina
The Stormwater Permitting Unit received a complete Stormwater Management Permit
Application for Mills River Elementary School on February 20, 2008, Staff review of the plans
and specifications has determined that the project, as proposed, will comply with the Stormwater
Regulations set forth in Title 15A NCAC 2H.1000 and Session Law 2006-246. We are forwarding
Permit No. SW 1080104, dated March 21, 2009, for the construction of the subject project.
This permit shall be effective from the date of issuance, March 21, 2008, until rescinded
and shall be subject to'the conditions and limitations as specified therein, and does not supersede
any other agency permit that may be required.
Please pay special attention to the Operation and Maintenance requirements in this perrm.r
Failure to establish an adequate system for operation and maintenance of the stormwatc:' management
system will result in future compliance problems.
If any parts, requirements, or limitations contained in this permit are unacceptable, you
nave the right to request an adjudicatory hearing upon written request within sixty (60) days
following receipt of this permit. This request must be in the form of a written petition, colif'ornling
to Chapter 150B of the North Carolina General Statutes, and tiled with the Office of
Administrative Hearings, P.O. Drawer 27447, Raleigh, NC 27611-7447. Unless such detlialv)-)
are made this permit shall be final and binding.
This proiect will be kept on file at the Asheville Regional Office. If you have any
questions, or need additional information concerning this matter, please contact Roger Edwards at
the Asheville Regional Office, 828-296-4500.
Sincerely,
for Coleen It. Sullins
cc: Weston Boles, McKim & Creed
Asheville egi6nal:Offi�e
(":ventral Files
Or.,:
,i'�Fx'rrrrr�r�
P44i'lt Caahfi::° ?iris ;;n zXWater Quality 1617 Mail Service Center Raleigh, NC 27699-1617 Phone [phone] custo-ner Service —
1=ac Location: 512 N. Salisbury St. Raicigh, NC 27604 Fax [phone]-G27.6743
An Equal OP1.orturity/Aftirmative Action Employer — W16 Recycled110% Post Consumer Paper

In
State Stormwater Management Systems
Permit No.: SW1080104
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
Mills River Elementary School
Henderson County, North Carolina
FOR THE
construction, operation and maintenance of one wet detention ponds in compliance with the
provisions of Session law 2006-246 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 20. 2018, and shall be
subject to the following specified conditions and limitations:
I. DESIGN STANDARDS
1. This permit is effective only with respect to the nature: and volurne of btormwater
described in the application and other supporting data.
2. This stormwater system has been approved for the management of stormwater runoff as
described herein and in compliance with the provisions of Session law 2006-246 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.
3. The tract will be limited to the amount of built -upon area indicated herein 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.
5. The runoff from all built -upon area within the permitted drainage area of this project must
be directed into the permitted stormwater control system.
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State Stormwater Management Systems
Permit No.: SW1080104
L
i
6. The following
design criteria have been provided in the wet detention pond and must be
maintained at design condition:
a.
Drainage Area, ft2:
501,088
b.
Total Impervious Surfaces, ft2:
253,774
C.
Pond Depth, feet:
3
d.
TSS removal efficiency:
85
e.
Permanent Pool Elevation, FMSL:
2102 .
f.
Permanent Pool Surface Area, ft2:
8,946
g.
Permitted•Storage Volume, ft3:
26,727
h.
Temporary Storage Elevation, FMSL:
2103.87
i.
Controlling Orifice (0 pipe in inches):
2
j.
Permitted Forebay Volume, fe:'
5,221
k.
Design Storm (Quality), inches:
1 inch
L � ' '
Receiving Stream/River Basin:
Bolyston Creek, French Board
M. Stream Index Number: 6-52-(6.5) "
n. Classification of Water Body: WS-!V.
II. SCHEDULE OF COMPLIANCE
1. 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.
2. During construction, erosion shall be kept to a minimum and any eroded areas of the
system will be repaired immediately.
3. The permittee shall at all times 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 revegetation of slope, and the vegetated filter.
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 structurP,'orifice device, flow spreader,
catch basins and piping.
g. Access to the outlet structure must be available at all times.
4. Records of maintenance activities must be kept and made available upon request to
authorized personnel of DWQ. The records will indicate the date, activity, name of
person performing the work and what actions were taken.
Pace 2 of 4

State Stormwater Management Systems
Permit No.: SW1080104
5. Decorative spray fountains will be allowed in the stormwater treatment system, subject to
the following criteria:
a. The fountain must draw its waterjfrom less than 2' below the permanent pool
surface.
b. Separated units, where the nozzle, pump and intake are connected by tubing,
may be used only if they draw water from the surface in the deepest part of the
pond.
c. The falling water from the fountain must be centered in the pond, away from the
shoreline.
6. The facilities shall be constructed as shown on the approved plans. This permit shall
become voidable unless the facilities are constructed in accordance with the conditions
of this permit, the approved plans and specifications, and other supporting data.
7. Upon completion of construction 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.
8, 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.
9. Access to the stormwater facilities shall be maintained via appropriate easements at all
times.
10. The permittee shall submit to the Director and shall have received approval for revised
glans, 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.
G. 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. Tho
project area is defined as all property owned by the permittee, for which
Sedimentation and Erosion Control Plan approval was sought.
f. Filling`in, altering, or piping of any vegetative conveyance shown on the approved
plan.
1. The permittee shall submit final site layout and grading plans for any permitted future
areas shown on the approved plans, prior to construction.
2. A copy of the approved plans and specifications shall be maintained on file by the
Parmittee for a minimum of ten years from the date of the completion of construction.
1 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 anti
ce0fication in writing to the Director that the changes have been made.
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State Stormwater Management Systems
Permit No.: SW1080104 t
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 formal
permit transfer request to the Division of Water Quality, accompanied by a completed
name/ownership change form, documentation from the parties involved, and other
supporting materials as may be appropriate. 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.
2. 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 accordance with
North Carolina General Statute 143-215.6A to 143-215.6C.
3. 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.
4. In the event that the facilities fail to perform satisfactorily, including the creation of
nuisance conditions, the Permittee shall take immediate corrective action, including
-•hose as may be required by this Division, such as the construction of additional or
;replacement stormwater management systems.
5. 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.
6. The permit may be modified, revoked and reissued or terminated for cause. The filing of
a request for a permit modification, revocation and reissuance or termination does not
stay any permit condition.
7. 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.
8. Approved plans'and specifications for this project are incorporated by reference and are
enforceable parts of the permit.
9. The permittee shall notify the Division any name, ownership or mailing address changes
within 30 days.
Permit issued this the 21th day of March, 20.08'.
NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION
u
for Coleen H. Sullins, Director
Division of Water Quality
By Authority of the Environmental Management Commission
Page 4 of 4

r
State Stormwater Management Systems
Permit No.: SW 1080104
Designer's Certification
Mills River Elementary School
Henderson County;.North Carolina
1, , as a duly registered in the State of
North Carolina, having been authorized to observe (periodically/ weekly/ full time) the
construction of the project,
(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.
The checklist of items on page 2 of this form is included in the Certification.
Noted deviations from approved plans and specification:
Signature
Registration Number
Date
0
SEAL
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State Stormwater Management Systems
Permit No.: SW 1080104
Certification Requirements:
1.
The drainage area to the system contains approximately the permitted acreage.
2.
The drainage area to the system contains no more than the permitted amount of
built -upon area.
3.
All the built -upon area associated with the project is graded such that the runoff
drains to the system.
4.
All roof drains are located such that the runoff is directed into the system.
5.
The outlet/bypass structure elevations are per the approved plan.
6.
The outlet structure is located per the approved plans.
7.
Trash rack -is provided on the outlet/bypass structure.
8.
All slopes are grassed with permanent vegetation.
9.
Vegetated slopes are no steeper than 3:1.
10.
The inlets are located per the approved plans and do not cause short-circuiting of
the system.
11.
The permitted amounts of surface area and/or volume have. been provided. _
12.
Required.drawdown devices are correctly sized per the approved plans. -
13.
All required design depths are ;provided.
14.
All required parts -of the system are provided, such as a vegetated shelf, and a
forebay.
15.
The required system dimensions are provided per the approved plans.
cc: NCDENR-DWQ Mooresville Regional Office
0
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