20090859 Ver 1_More Info Letter_20101028

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NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Coleen H. Sullins Dee Freeman
Governor Director Secretary
October 28, 2010
DWQ# 09-0859v2
Stanly County
Mr. Greg Simmons
Charlotte Pipe and Foundry
P. O. Box 35430
Charlotte, NC 28208
Subject Property: Oakmont Charlotte Pipe and Foundry
REQUEST FOR MORE INFORMATION: STORMWA TER MANAGEMENT PLAN (SMP)
Dear Mr. Simmons:
On October 7, 2010, the 401/Wetlands Permitting Unit of the Division of Water Quality (DWQ) received
a stormwater management plan (SMP) dated October 4, 2010 (Engineer's Seal) along with supporting
information for the purpose of meeting the SMP condition (#5) of the 401 Water Quality Certification
issued by the DWQ on August 27, 2009. Please provide the following information so that we may
continue to review your project and prevent return of your application as required by 15A NCAC
2H.0506:
Additional Information Requested:
Wet Ponds:
a. Please combine the two forebays in Pond #I into one, and relocate the outlet structure in
order to elongate the flow path length.
b. Please start accumulating the pond volume from the sediment clean out elevation.
c. Please provide seasonal high water table (SHWT) information on the supplement form, and
include a soil report in which the soil test borings are conducted at the pond locations. This
information is pertinent to the permanent pool elevation.
d. Please match the permanent pool volume for Pond #2 and the ballast pad dimensions of the
outlet structures on the supplement form, the plan sheets and design calculations report.
2. Level Spreader - Vegetated Filter Strip (LS-VFS):
a. The level spreader lip and footing shall be constructed of reinforced concrete material.
b. Please follow the new design guidelines as summarized in Table 8-1 in the DWQ BMP
Manual. LS-VFS used for different purposes have different design requirements. As
discussed with your engineer, please use the available space, to the maximum extent
practicable, to provide an acceptable length of level spreader for the type of filter strip and
flow directed to it.
c. Please include design information for the flow-splitting device - e..g amount of flow being
diverted to the LS, the sizing of the pipes and determination of their invert elevations or any
weir structure.
d. Include construction notes for the LS-VFS
401 OversighUExpress Review Permitting Unit
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
Location: 2321 Crabtree Blvd., Raleigh, North Carolina 27604
Phone: [phone] FAX: [phone]
Internet: http:llh2o.enr.state.nc.uslncwetlands/
NorthCarolina
Naturally
An Equal Opportunity 1 Affirmative Action Employer
Oakmont Charlotte Pipe and Foundry- SMP
Stanly
Page 2 of 2
October 28, 2010
Please respond by sending two (2) copies of the above information and any revisions in writing. This
letter only addresses the application review and does not authorize any impacts to wetlands, waters or
protected buffers. Please be advised that any impacts approved within your certification cannot occur
until the SMP is approved.
Thank you for your attention to this matter. If you have any questions or wish to discuss these matters
further please do not hesitate to call Joseph Gyamfi at 919-733-1786.
Si erely _
Ian McMillan, Acting Supervisor
401 Oversight/Express Review Program
CBK/jg
cc: File copy
Alan Johnson - DWQ Mooresville Regional Office
Matt Bramwell, PE, LandDesign, 223 North Graham Street, Charlotte, NC 28202