19970616 Ver 1_Modifications_20021107

?01 cRQ Michael F. Eas6c-y, Governor
William G. Ross J, r., Secretary
?O G North Carolina Department of Environment and Natural Resources
t? Alan W. Klimek, F.E. Director
-i Division of Water Quality
o -c
November 7, 2002
Mr. Gregory J. Thorpe, Ph.D., Manager
NCDOT Planning and Environmental Branch
1548 Mail Service Center
Raleigh, NC, 27699-1548
Dear Dr. Thorpe:
Re: MODIFICATION to Water Quality Certification Pursuant to §401 of the Federal Clean Water
Act, Proposed US 421 Relocation from west of South Fork of the New River to east of thw Blue
Ridge Parkway. Watauga County.
TIP Project Nos. R-529 BA, BB and BD.
DWQ Project No. 970616. COE #199707161.
The Division of Water Quality has reviewed your submittal for a Modification to §401 Water Quavlity
Certification Number 3185 for the aforementioned project. Review of your application revealed itt
lacking necessary information required for making an informed permit decision. The permit app&cation
was deficient in the following areas:
1. Existing Stream Design
The existing stream does not appear to have been designed and/or constructed properly, as smch,
DWQ agrees that a new design is in order. .
2. In Stream Bed Material and Bank Stabilization
The proposed channel cross sections indicate a specification for "bed material" that is 0.6 meters
thick for the entire channel and over-bank area. However, no specification was provided incificating
the size or gradation of the material. The purpose and nature of the material is not discusse(tL.
Additionally, no sediment transport analysis, shear stress analysis or other modeling was provided
to support the need for such an approach. Finally, it is not clear as to how this approach relattcs to
natural channel design techniques. Although channel armoring may be needed at time, the Mvision
of Water Quality does not allow armored channels to count as compensatory mitigation.
3. Riparian Buffers and Planting Plan
A planting plan must be provided for the proposed stream buffers. The planting plan should
include tree planting densities of the appropriate native species that will result in a survival rarte of
320 trees per acre after five years. Please revise the site plans to include the extent and naturm of
the plantings and buffers.
4. Stormwater Inlet Location/Protection
Please locate any stormwater outlets to the proposed restored stream on the site plans. Please.
provide the means of stabilizing the stormwater outlets on the site plans.
North Carolina Division of Water Quality, 401 Wetlands Certification Unit,
1650 Mail Service Center, Raleigh, NC 27699-1650 (Mailing Address)
2321 Crabtree Blvd., Raleigh, NC 27604-2260 (Location)
919-733-1786 (phone), 919-733-6893 (fax), http://h2o.enr.state.nc.us/ncwetiands/
AM
Please note that the Internal Technical Guide for Stream Work in North Carolina (April 2001), and other
documents and information can be downloaded from the Wetlands Unit web site at
http://h2o.ehnr.state.nc.us/ncwetlands/restore.html.
Pursuant to 15A NCAC 2.11.0507(a)(3), the permit application will remain on hold until we are supplied
the necessary information. Furthermore, until the information is received by the NC Division of Water
Quality, we request (by copy of this letter) that the US Army Corps of Engineers continue to place the
permit application on hold.
We look forward to working with you to expedite the processing of your permit application. If you have
any questions or require additional information, please contact Cynthia F. Van Der Wiele at
919.733.5715.
Sincerely,
. D< m y'
ter Quality Certific ion Program
cc: Wilmington District COE
John Thomas, USACE Raleigh Field Office
Todd St. John, DWQ
Jennifer Frye, NCDWQ Winston-Salem Regional Office
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