20070814 Ver 1_More Info Received_20070717

Laurel Park Elementary School - DWQ project number 07-0814
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Below are responses to DWQ's request for more information dated June 19, 2007.
1. Please see the re-submitted sheet C0.7, which now shows the 0.27 acres of wetland
impacts and a cross section showing the fill slopes on the wetland.
2. A letter from EEP accepting non-riparian mitigation has been included.
3. All stormwater from the site is being routed to the extended detention wetland. Sheet
C0.9 shows all drainage area draining to the extended detention wetland. This site is
located at the high area in the watershed and is bounded by a major road and a railroad
track. These features prohibit offsite flow from coming on to the site.
4. An extended detention worksheet has been provided along with explanations and
references to the requested calculations, plan sheets, drainage plan, and fully executed
operations and maintenance agreement (note that we have included one original signed
and notarized agreement and 4 copies of the agreement).
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~ r William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
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p -~ Coleen H. Sullins, Director
Division of Water Quality
June 19, 2007
DWQ Project # 07-0814
a~~Wake County
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CERTIFIED MAIL: RETURN RECEIPT REQUESTED -~ ~~~~ ,~~"; ~~
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Mr. Randy Stephens :~~,~~~ ~q~ ``R~~
WCPSS: Wake County Board of Education ~`' ~.=~,
3600 Wake Forest Road e1F4;, ~... '~ ~`~`~,~'
Raleigh, NC 27527 `"- ~~`
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Subject Properly: Laurel Park Elementary School
Ut to Williams Creek [030402, 27-43-2, WSIII, NSW]
REQUEST FOR MORE INFORMATION
Dear Mr. Stephens:
On May 11, 2007, the Division of Water Quality (DWQ) received your application dated May 9, 2007, to
fill or otherwise impact 0.27 acres of 404/wetland, and 0.00 square feet of Zone 1 Neuse River basin
protected riparian buffers and 0.00 square feet of Zone 2 Neuse River basin protected riparian buffers to
construct a residential subdivision. The DWQ has determined that your application was incomplete
and/or provided inaccurate information as discussed below. The DWQ will require additional
information in order to process your application to impact protected wetlands and/or streams on the
subject property. Therefore, unless we receive five copies of the additional information requested below,
we will have to move toward denial of your application as required by 15A NCAC 2H .0506 and will
place this project on hold as incomplete until we receive this additional information. Please provide the
following information so that we may continue to review your project.
Additional Information Requested:
1. Please show all wetland impacts including fill slopes on the site plan. A site plan should be
provided that shows the wetland area to be impacted by the multiuse facilities and playgrounds.
2. You have requested non-riparian mitigation, but the EEP has accepted riparian mitigation. Please
clarify this discrepancy.
3. Please show the drainage area of the proposed extended detention wetland. All stormwater
draining from the site must be routed to the extended detention wetland (or other BMP
appropriate for Nutrient Sensitive Waters per General Certification 3631).
4. Please provide a completed Extended Detention Wetland Worksheet as well as all information
listed under the Required Items. (The worksheet is available at the DWQ 401 Unit web site at:
http://h2o.enr.state.nc.us/ncwetlands/wetlndwk.pdf). As you complete the worksheet, please
reference the 1999 DWQ Stormwater BMP Manual and verify that the proposed design for this
BMP is in compliance with the manual.
401 Oversight/Express Review Permitting Unit
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604
Phone: [phone] /FAX [phone] /Internet: http://h2o.enr.state.nc.us/ncwetlands
An Equal Opportunity/Affirmative Action Employer - 50% Recycled/10% Post Consumer Paper
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WCPSS: Wake County Board of Education
Page 2 of 2
June 19, 2007
Please submit this information within 30 calendar days of the date of this letter. If we do not receive this
requested information within 30 calendar days of the date of this letter, your project will be withdrawn
and you will need to reapply with a new application and a new fee.
This letter only addresses the application review and does not authorize any impacts to wetlands, waters
or protected buffers. Please be aware that any impacts requested within your application are not
authorized (at this time) by the DWQ. Please call Ms. Cyndi Karoly or Mr. Ian Mc plan at 919-733-
1786 if you have any questions regarding or would like to set up a meeting to discyl~s this matter.
CBKlijm
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Sin ely,
Cyndi Karoly, Supervisor
401 Oversight/Express Review Permitting Unit
cc: Lauren Cobb, DWQ Raleigh Regional Office
USAGE Raleigh Regulatory Field Office
File Copy
Central Files
Corky Botkin, Dewberry & Davis, Inc., 2301 Rexwoods Drive, Suite 200, Raleigh, NC 27607
Filename: 070814La urelParkEle men tarySchool(W a ke)On_Hold

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o~stem
PROGRAM
May 16, 2007
Randy Stephens
Wake County Public Schools
3600 Wake Forest Road
Raleigh, NC 27609
Project: Laarel Park Elementary School County: Wake
This acceptance letter replaces one dated May 9, 2007. The purpose of this letter is to notify you that the North Carolina
Ecosystem Enhancement Program (NCEEP) is willing to accept payment for impacts associated with the above referenced
project. Please note that this decision does not assure that the payment will be approved by the permit issuing agencies as
mitigation for project impacts. It is the responsibility of the applicant to contact these agencies to determine if payment to the
NCEEP will be approved.
This acceptance is valid for six months from the date of this letter and is not transferable. If we have not received a copy of
the issued 404 Permit/401 Certification/CAMA permit within this time frame, this acceptance will expire. It is the
applicant's responsibility to send copies of the permits to NCEEP. Once NCEEP receives a copy of the permit{s) an invoice
will be issued based on the required mitigation in that permit and payment must be made prior to conducting the authorized
work. The amount of the In Lieu Fee to be paid to NCEEP by an applicant is calculated based upon the Fee Schedule and
policies listed at www.nceep.net.
Based on the information supplied by you the impacts that may require compensatory mitigation are summarized in the
followine table.
Neuse
03020201 Stream (feet) Wetlands (acres) Buffer I
(Sq. Ft.) Buffer II
(Sq. Ft.)
Cold Cool Warm Ri azian Non-Ri azian Coastal Marsh
Impacts 0 0 0 0 0.27 0 0 0
Credits 0 0 0 0 0.54 0 0 0
Upon receipt of payment, EEP will take responsibility for providing the compensatory mitigation. If the regulatory agencies
require mitigation credits greater than indicated above, and the applicant wants NCEEP to be responsible for the additional
mitigation, the applicant will need to submit a mitigation request to NCEEP far approval prior to permit issuance. The
mitigation will be performed in accordance with the Memorandum of Understanding between the N. C. Department of
Environment and Natural Resources and the U. S. Army Corps of Engineers dated November 4, 1998.
If you have any questions or need additional information, please contact Kelly Williams at [phone].
Sincerely,
Willia .Gilmore, PE
Director
~~
cc: Cyndi Karoly, Wetlands/40I Unit
Thomas Brown, USACE-Raleigh
Eric Kulz, DWQ-Raleigh
Corky Botkin, agent
File
~.~stor' .. ~ ... Pro Otrr ft~
~~~~
North Carolina Ecosystem Enhancement Program, 1652 Mail Service Center, Raleigh, NC 27699-1652 / 919-715-0476 / www.nceep.net

DWQ Project No. ~-]- ~ ~ ) y
DIVISION OF WATER QUALITY - 401 EXTENDED DETENTION (and POCKET*) WETLAND WORKSHEET
I. PROJECT INFORMATION (please complete the following information):
Project Name : Lawc+G1 "pork C)enen~cry
Contact Person: Cork.., J~3.r1-k;,n Phone Number:
For projects with multiple basins, specify which basin this worksheet applies to:
Permanent Pool Elevation
Temporary Pool Elevation
Permanent Pool Surface Area
Drainage Area
Impervious Area
Forebay Surface Area
Marsh 0"-9" Surface Area
Marsh 9"-18" Surface Area
Micro Pool Surface Area
sq. ft. (water surface area at permanent pool elevation)
ac. (on-site and off-site drainage to the basin)
ac. (on-site and off-site drainage to the basin)
sq. ft. (at permanent pool elevation approximately 15%)*
sq. ft. (at permanent pool elevation approximately 35%)*
sq. ft. (at permanent pool elevation approximately 35%)*
sq. ft. (at permanent pool elevation approximately 15%)*
~,,i beloc,a elevA-ly`a/t `Ilz.1-Ft.
Temporary Pool Volume ~ ~Z ~jOO cu. ft. (volume detained on top of the permanent pool)
Z! ~ 337 G u . fit. ae {-w'ne~Q ~o r alt 1 `~ ev~n+
SA/DA used 1.3N (surface area to drainage area ratio)*
Diameter of Orifice Z.5 in. (draw down orifice diameter)
II. REQUIRED ITEMS CHECKLIST
Initial in the space provided to indicate the following design requirements have been met and supporting documentation is attached. !f a
requirement has not been met, attach an explanation of why. At a minimum, a complete stormwater management plan submittal includes
a worksheet for each BMP, design calculations, plans and specifications showing all BMPs and outlet structure details, a detailed
drainage plan and a fully executed operation and maintenance agreement. An incomplete submittal package will result in a request for
additional information and will substantially delay final review and approval of the project
Applicants Initials
GR, The temporary pool controls runoff from the 1 inch rain.
C6 - cond:fioru;) The basin side slopes are no steeper than 3:1. -- [n~)~,~+;o~ ;S c~~ctie~
C8 A planting plan for the marsh areas with plant species and densities is provided.
C.13 Vegetation above the permanent pool elevation is specified.
G8 _ An emergency drain is provided to drain the basin.
The temporary pool draws down in 2 to 5 days.
(_ ~ Sediment storage is provided in the permanent pool.
CB A sediment disposal area is provided.
CB Access is provided for maintenance.
(~ A site specific, signed and notarized operation and maintenance agreement is provided.
Cf3 The drainage area (including any offsite area) is delineated on a site plan.
(.R Access is provided for maintenance.
CB Plan details for the wetland are provided.
Plan details for the inlet and outlet are provided.
C8 A site specific operation and maintenance agreement, signed and notarized by the responsible party is provided (see
http:l/h2o.ehnr.state.nc.us/ncwetlandsloandm.doc).
"Pocket Wetlands have different design parameters and are only assumed to remove 35% TSS -See pp.19and 20 of the NC DENR
stormwater BMP Manual, April 1999.10% open water, 50% high marsh, 40% low marsh.
y ~~ (o ft. (elevation of the orifice invert out)
y 12.1 ft. (elevation of the outlet structure invert in)

Discussed pertinent. issues of concern with Annett Lucas on June 26, 2007
The temporary pool controls runoff from the 1 inch rain. - We have provided documentation showing
that the extended detention wetland will effectively control runoff from the site for the 1-yr/24-hr
storm event for post development conditions and control and treat the first inch of runoff from the
total project site event with a draw down time between 2 and 5 days. See the attached Extended
Detention Wetland Calculations (Malcom's Spreadsheet). The attached calculations also support
that the pond will effectively pass the 10-, 25-, and 100- year design events.
The basin side slopes are no steeper than 3:1 -Side slopes for areas where new grading will occur
will be graded no steeper than 3:1. The existing grade of the eastern and southern banks of the
extended detention wetland will remain at an approximate 2:1 slope. This is an existing area with
established vegetation and does not require re-grading to a new slope to provide stabilization.
Further, re-grading this area has been determined to be impractical due to existing easement
constraints (see Sheet C0.7).
A planting plan for the marsh areas with plant species and densities isprovided. -Please see Sheet C0.29
- All plantings and densities are provided.
Vegetation above the permanent pool elevation is specified. -Please see Sheet C0.29 -See Note 2 for
Permanent Upland Seeding.
An emergency drain is provided to drain the basin. -See sheet C0.19. An emergency drain has been
provided.
The temporary pool draws down in 2 to 5 days. -Temporary pool draw down is appropriately designed
to be between 2 and 5 days -See the attached Extended Detention Wetland Calculations.
Sediment storage is provided in the permanent pool. -The forebay provides sediment storage and
maintenance access has been provided for routine removal (see Sheet C0.7).
A sediment disposal area is provided. - A sediment disposal area has been provided (see Sheet C0.7).
Access is provided for maintenance. -Access to the extended detention wetland from a paved site
road has been provided. A 5:1 sloping path has been provided all the way down and into the
wetland forebay (see Sheet C0.7). This access will provide a necessary point of access for the
entire extended detention wetland area. The forebay will be able to be directly accessed by a
backhoe to remove sediment. There will be access to the micro-pool and marsh areas for hand
maintenance, and if necessary the extended detention wetland can be drained to allow for
equipment access. If the outfall needs to be repaired or requires heavy equipment, the 3:1 slopes
of the western banks will provide sufficient access for a backhoe, grader, and maintenance
personnel. It is anticipated that the forebay will serve to remove the normal sediment loading to
the extended detention wetland, so it is anticipated that maintenance required beyond this point
will be limited.
A site specific, signed and notarized operation and maintenance agreement is provided. - A site specific
operation and maintenance agreement, signed and notarized by the responsible party is provided.
The drainage area (including any offsite area) is delineated on a site plan. -Sheet C0.9 shows all
drainage area draining to the extended detention wetland. This site is located at the high area in
the watershed and is bounded by a major road and a railroad track. These features prohibit offsite
flow from coming on to the site.
Access is provided for maintenance. -Access for maintenance has been discussed above.
Plan details for the wetland are provided. -Sheets C0.19 and sheet C0.29 provide necessary details
for the extended detention wetland.
Plan details for the inlet and outlet are provided. -Sheet C0.19 has details for the inlet and outlet of the
extended detention wetland.

copy
WETLAND DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The wetland detention basin system is defined as the wetland detention basin, pretreatment including forebays
and the vegetated filter if one is provided.
Maintenance activities shall be performed as follows:
After every significant runoff producing rainfall event and at least monthly:
a. Inspect the wetland detention basin system for sediment accumulation, erosion, trash accumulation,
vegetated cover, and general condition.
b. Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs within
2 to 5 days as designed.
2. Repair eroded areas immediately, re-seed as necessary to maintain good vegetative cover, mow
vegetative cover to maintain a maximum height of six inches, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the wetland detention basin system semi-annually or when depth is
reduced to 75% of the original design depth (see diagram below). Removed sediment shall be disposed
of in an appropriate manner and shall be handled in a manner that will not adversely impact water quality
(i.e. stockpiling near a wetland detention basin or stream, etc.).
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 406.4 feet in the main pond, the sediment shall be removed. If the
elevation of the marsh areas exceed the permanent pool elevation, the sediment should be removed to
design levels. This shall be performed by removing the upper 6 inches of soil and stockpiling it. Then the
marsh area shall be excavated six inches below design elevations. Afterwards the stockpiled soil should
be spread over the marsh surface. The soil should not be stockpiled for more than two weeks.
When the permanent pool depth reads 405.65 feet in the forebay, the sediment shall be removed.
BASIN DIAGRAM
(fill in the blanks)
Permanent Pool Elevation 407.6
Sediment moval EI. 405.6 7 /°
-------------- -- Sediment Removal Elevation 406.4 75%
2 ------------------------------------------- *-----~
Bottom E vation 405.0 5%
FOREBAY MAIN POND
5. Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These
plants shall be encouraged to grow along the vegetated shelf and forebay berm.
Wetland planting densities in the marsh areas should be maintained by replanting bare areas as needed.
Wetland plants should be encouraged to grow in the marsh areas.
Page 1 of 2

6. if the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
7. All components of the wetland detention basin system shall be maintained in good working order.
8. Level spreaders or other structures that provide diffuse flow shall be maintained every six months. All
accumulated sediment and debris shall be removed from the structure, and a level elevation shall be
maintained across the entire flow spreading structure. Any down gradient erosion must be repaired and/or
replanted as necessary.
I acknowledge and agree by my signature below that I am responsible for the performance of the seven
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.
Print name: Randy Stephens
Title: Protect Manager
Address: 3600 Wake Forest Road
Phon
Sign<
Date
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, ~~ ~ ~^ah " ~~" ~~ ~~ ~~'+~3 , a Notary Public for the State of N ~R~
County of ~~%K-c_. , do hereby certify that ~Gthar!N ~. o~'f~S
personally appeared before me this _~ day of Zb0? ,and acknowledge the due
execution of the forgoing wetland detention basin maintenance requirements. Witness my hand and official
seal,
SEAL
My commission expires ~ - 02 7 ' ~ ~/
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