20081058 Ver 1_More Info Received_20080811

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XRO'
OUNT DEPARTMENT OF
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August 7, 2008
Cyndi Karoly
401 Oversight/Express Review Permitting Unit
Division of Water Quality
1650 Mail Service Center
Raleigh, NC 27699-1650
Dear Ms. Karoly,
In response to your letter dated July 14, 2008, we are resubmitting for your review five sets of revised
plans with the additional information which you requested. To my knowledge, all the additional
information you have requested has been addressed in the revisions or within the attached response
sheet.
If there is any additional information required for this permit to be approved, please contact me at 252-
972-1122.
Sincerely,
Anthony Mancari, P.E.
Assistant City Engineer, Water & Sewer
AU G 1 ]_ 2008
DENR - wSTOEtM'NA R 6RANCi?
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331 South Franklin Street • Post Office Box 1180 • Rocky Mount, North Carolina 27802-1180
Telephone [phone] • Fax [phone] • Website: www.rockymountne.gov
ROCKY
MOUNT DEPARTMENT OF
» o a r » » . ENGINEERING
Maple Cree Interceptor Sewer
Maple Creek (030302, 28-66, WSIV, NSW)
In response to your letter dated July 14, 2008 and a conversation with Mr. Ian McMillian on July 17th,
2008, we offer the following response.
1. Please indicate all stream impacts including all fill slopes, dissipaters, and bank stabilization on
the site plan.
An erosion control plan has been provided. There are no stream crossings or anticipated stream
impacts and all areas will be returned to original grade.
2. Please indicate all wetland impacts including fill slopes on the site plan.
Wetland impacts are identified within the plan sheets and have been noted that there will be
mechanical clearing within the easement areas. All other impacts are temporary and final
grades will not be altered.
Please enumerate all riparian buffer impacts on the site plan and clearly label impacts (Buffer
Impact 1, etc.).
Buffer and wetland impacts have been identified and numbered on the plans.
4. Please locate all of the protected riparian buffers as overlays on the site plan, clearly showing
Zone 1 and Zone 2.
All protected riparian buffers and zones have been annotated on the plans.
5. Please provide a qualitative indirect and cumulative impact analysis for the project.
Please see attached analysis.
331 South Franklin Street • Post Office Box 1180 • Rocky Mount, North Carolina 27802-1180
Telephone [phone] • Fax [phone] • Website: www.rocAymountnc.gov
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ROCKY
MOUNT DEPARTMENT OF
R. I... ENGINEERING
August 7, 2008
Division of Water Quality
401 Wetlands Unit
1650 Mail Service Center
Raleigh, NC 27699-1650
Re: Cumulative Impacts Statement for 401 Water Quality Certification
This memorandum is to address the requirements of Section XIV - Cumulative Impacts within the Pre
Construction Notification Form.
Proi ect:
The City of Rocky Mount is planning on extending an 18" gravity sewer outfall approximately 7000
linear feet to be in position to serve areas of the city anticipated with moderate residential growth. In
addition, this line would be in position to be extended to areas of the city currently developed but which
lack municipal sewer service. The largest cumulative effect of this project will be the residential growth
and development resulting from sewer availability in rural areas.
Study Area Boundaries
The current project calls for the gravity outfall to be extended from Warrington Court (a residential area)
to Halifax Road. The alignment, upon leaving the residential area, traverses existing agricultural and
wooded properties which border Maple Creek and associated wetland and lowland areas. Where the
project ties into the existing outfall constructed in the 1970s, wetlands are prevalent. However, every
effort was made to design the most direct means to leave the wetland area and continue on higher
ground. As evident from the plans, once the alignment leaves the wetlands near the beginning of the
project it purposely bypasses them for the remainder of the project.
Study Area Needs
The City of Rocky Mount is experiencing growth on its western boundary and although water service is
reasonably available, there is no sewer availability.
Notable Features Inventory
Potentially affected areas include Maple Creek and its associated tributaries and surrounding wetlands.
Maple Creek is within the Tar-Pamlico river basin and hence is subject to the Tar-Pamlico Riparian
Buffer rules and nutrient loading requirements.
Other than within the existing residential area and the roadways being crossed, there is currently no
impervious area within the study area. However, the City of Rocky Mount's land development codes,
stormwater management design standards, erosion control program, annual BMP inspection
331 South Franklin Street • Post Office Box 1180 • Rocky Mount, North Carolina 27802-1180
Telephone [phone] • Fax [phone] • Website: engineering. rockymountnc.gov
ROCKY
OUNT DEPARTMENT OF
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requirements and water supply watershed requirement of a max impervious area of 70%, assists in
controlling and monitoring water quality.
Cause-Effect Relationships between past, present and future actions and downstream water quality
The major pollutants identified within Rocky Mount and the Tar Pamlico River Basin are sediment,
nitrogen and phosphorous, all of which are a result of increased impervious area associated with
development. The Rocky Mount stormwater program operates under a permitted NPDES authorization
and is audited at least yearly. As mentioned previously the erosion control program, the Rocky Mount
drainage design standards, BMP inventorying and inspections and water supply watershed requirements,
coupled with the NCDENR's Tar Pamlico Riparian Buffer and Nutrient Management requirements aim
at controlling these pollutants.
Identification of significant ICI issues
As discussed, the most pronounced impact that will result from this project is residential development in
formally rural areas. Associated with this development is increase in impervious area and water quality
degradation. However, considering the controls measured in the previous steps, it can be deemed that
these are sufficient to address the most significant ICI issue.
If you have any additional questions, or if I can be of assistance please contact me at 252-972-1122.
CITY OF ROCKY MOUNT
A ony C. Mancari P.E.
sistant City Engineer/Water Resources
331 South Franklin Street • Post Office Box 1180 • Rocky Mount, North Carolina 27802-1180
Telephone [phone] • Fax [phone] • Website: engineering. rockymountnc.gov