20080322 Ver 1_More Info Letter_20080409

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Michael F. Easley, Governor
William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
Coleen H. Sullins, Director
Division of Water Quality
April 9, 2008
CERTIFIED MAIL: RETURN RECEIPT REQUESTED
Drayton Reserve Subdivision
Attn: Mr. Jeffrey L. Ward
818 South White Street
Wake Forest, NC 27587
Subject Property: Drayton Reserve Subdivision
REQUEST FOR MORE INFORMATION
Dear Mr. Ward:
DWQ EXP No. 08-0322
Wake County.
On April 7, 2008, the Express Review Program of the Division of Water Quality (DWQ) received your
application for the above referenced project. The DWQ has determined that your application will require
additional information. Please provide the following information so that we may continue to review
your project and prevent denial of your application as required by 15A NCAC 2H .0506:
Additional Information Requested
1. Wet Ponds:
a. It appears that the proposed wet ponds will likely drain adjacent wetlands. Please provide a
clay liner or specify that soil material shall be compacted to a suitable permeability (such as
specifications for a landfill liner).
b. Inlet and outlet protections have not been provided or shown on plans. Although inlet pipes
appear to discharge below permanent pool levels, and outlet pipes discharge into level
spreader channels, it is imperative to provide some minimum inlet protection and channel
stability.
c. Also, please specify on the plans that level spreaders are constructed of concrete lip and
reinforced channels.
d. Wet pond 1:
i. All of the stormwater runoff for the first inch of rainfall must meet 30% Nitrogen
removal prior to entering the existing wetland (30 feet of the vegetated filter strip
must be located outside of the existing wetland). Please redesign your BMP to reflect
this requirement.
ii. By our estimation, the surface area of the top of shelf for Wet pond 1 is 17,000ftz
maximum, giving a total volume of 25,100 ft' for the temporary volume, which is
less than the 25,457ft3 required. We recommend that the temporary pool elevation be
set at 253ft to create the needed additional volume.
401 Oversight 1 Express Review Permitting Unit
1650 Mail Service Center, Ralegh, North Carolina 27699-1650
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604
Phone: [phone] FAX [phone]Intemet: http://h2o.enr.state.nc.us/ncwetlands
None Carolina
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An Equal OpportunitylAffirmative Action Employer- 50% Recycled110% Post Consumer Paper

Drayton Reserve Subdivision
Page 2 of 2
Apri19, 2008
e. Wet pond 2:
i. The emergency spillway location with respect to the level spreader and vegetated
filter strip or vice-versa is not appropriate, unless the level spreader is sized for the
10-year storm.
ii. After addressing item (i) above, please provide design calculations to show that the
spillway shall be capable and stable to pass the discharge from the 10-year storm.
The spillway appears to serve as an overflow structure for all flows above the water
quality volume.
iii. The footprint of the level spreader -vegetated filter strip system is in the existing
power easement. Will you be able to install the level spreader in the power easement?
f. Wet pond 3:
i. The bypass swale shall have a minimum of 0.5 ft of freeboard. The proposed swale
has only 0.2 of freeboard.
2. Riparian Buffer Impacts
a. Impacts to Zone 2 of the Riparian buffer for the purpose of constructing stormwater BMPs
(as shown in Wet Pond 1 and 2) must be mitigated for. Please consider redesigning BMPs
such that Zone 2 is not impacted or provide Buffer mitigation at a rate of 1.5:1. If the impacts
cannot be avoided, the changes will need to be reflected on the PCN form and with and
NCEEP acceptance letter.
3. Bypass Channels
a. Bypass pipes and channels should be located at an angle such that erosion will not occur on
the far bank (perhaps to 75 degrees). Additionally, the width of bypass channels should be
minimized the maximum extent possible. If the width of the impact is greater than 10 feet in
width, mitigation will be required.
4. Scour Hole
a. Please provide details for all proposed scour holes.
Please respond within five (5) days of the date of this letter by sending two (2) copies of the above
information in writing. The Express Review Program is a process that requires all parties to participate in a
timely manner.
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 contact Joseph Gyamfi or Lia Myott at 919-733-1786 if you have any questions regarding or
would like to set up a meeting to discuss this matter.
CBK/lem/jg
Since ly,
Cyndi Karoly, Supervisor
401 OversightlExpress Review Permitting Unit

Drayton Reserve Subdivision
Page 3 of 3
April 9, 2008
cc: USACE Raleigh Regulatory Field Office
Lauren Witherspoon, DWQ Raleigh Regional Office
File Copy
Central Files
Jennifer A. Burdette, Burdette Land Consulting, Inc., 10212 Creedmoor Rd., Raleigh, NC 27615