HomeMy WebLinkAbout20100752_Scoping Comments_20061025> l\Q?0` `yQG William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
C13 r Alan W. Klimek, P.E. Director
> Division of Water Quality
U <
October 25, 2006
MEMORANDUM
To: Melba McGee
From: `-Sue Homewood, Division of Water Quality, Winston-Salem Regional Office
Subject: Comments on the Final Environmental Impact Statement related to proposed US 321
Improvements from existing Blackberry Road to Existing US 221 at Blowing Rock,
Caldwell and Watauga Counties, State Project No. 6.730001T, TIP R-2237C.
This office has reviewed the referenced document dated September 6, 2006. The Division of Water
Quality (DWQ) is responsible for the issuance of the Section 401 Water Quality Certification for
activities that impact Waters of the U.S., including wetlands. It is our understanding that the project as
presented will result in impacts to jurisdictional wetlands, streams, and other surface waters. The DWQ
offers the following comments based on review of the aforementioned document:
This project is being planned as part of the 404/NEPA Merger Process. As a participating team
member, the NCDWQ will continue to work with the team. NCDWQ reaffirms its
2. All of the named streams that this project drains to have a designation of Tr waters of the
State. DWQ recommends that the most protective sediment and erosion control BMPs be
implemented to reduce the risk of turbidity violations in trout waters. In addition, all
disturbances within trout buffers should be conducted in accordance with NC Division of
Land Resources and NC Wildlife Resources Commission requirements.
Review of the project reveals the potential for a small section of the project to drain to surface
waters classified as C, Tr, High Quality Waters of the State in the project study area. This is one of
the highest classifications for water quality. Pursuant to 15A NCAC 2H .1006 and 15A NCAC 2B
.0224, NC DOT will be required to obtain a State Stormwater Permit prior to construction.
3. The environmental document should provide a detailed and itemized presentation of the proposed
impacts to wetlands and streams with corresponding mapping. If mitigation is necessary as required
by 15A NCAC 211.0506(h), it is preferable to present a conceptual (if not finalized) mitigation plan
with the environmental documentation. Appropriate mitigation plans will be required prior to
issuance of a 401 Water Quality Certification.
4. Environmental assessment alternatives should consider design criteria that reduce the impacts to
streams and wetlands from storm water runoff. These alternatives should include road designs that
allow for treatment of the storm water runoff through best management practices as detailed in the
most recent version of NC DWQ Stormwater Best Management Practices, such as grassed swales,
buffer areas, preformed scour holes, retention basins, etc.
NQofthcarolina
tllCQ??tf
Transportation Permitting Unit
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604
Phone: 919-733-17861 FAX 919-733-68931 Internet: htto://h2o.enr.state.nc.us/ncwetlands
An Equal Opportunity/Affirmative Action Employer- 50% Recycled/10% Post Consumer Paper
October 25, 2006
DENR Project # 07-0120
Page 2 of 4
IV
5. After the selection of the preferred alternative and prior to an issuance of the 401 Water Quality
Certification, the NCDOT is respectfully reminded that they will need to demonstrate the avoidance
and minimization of impacts to wetlands (and streams) to the maximum extent practical. In
accordance with the Environmental Management Commission's Rules {1 5A NCAC 2H.0506(h)},
mitigation will be required for impacts of greater than 1 acre to wetlands. In the event that
mitigation is required, the mitigation plan should be designed to replace appropriate lost functions
and values. The NC Ecosystem Enhancement Program may be available for use as wetland
mitigation.
6. In accordance with the Environmental Management Commission's Rules {1 5A NCAC
2H.0506(h)}, mitigation will be required for impacts of greater than 150 linear feet to any single
perennial stream. In the event that mitigation is required, the mitigation plan should be designed to
replace appropriate lost functions and values. The NC Ecosystem Enhancement Program may be
available for use as stream mitigation.
Future documentation, including the 401 Water Quality Certification Application, should continue
to include an itemized listing of the proposed wetland and stream impacts with corresponding
mapping.
DWQ is very concerned with sediment and erosion impacts that could result from this project. NC
DOT should address these concerns by describing the potential impacts that may occur to the
aquatic environments and any mitigating factors that would reduce the impacts.
NC DOT is respectfully reminded that all impacts, including but not limited to, bridging, fill,
excavation and clearing, to jurisdictional wetlands, streams, and riparian buffers need to be included
in the final impact calculations. These impacts, in addition to any construction impacts, temporary
or otherwise, also need to be included as part of the 401 Water Quality Certification Application.
10. Where streams must be crossed, the DWQ prefers bridges be used in lieu of culverts. However, we
realize that economic considerations often require the use of culverts. Please be advised that
culverts should be countersunk to allow unimpeded passage by fish and other aquatic organisms.
Moreover, in areas where high quality wetlands or streams are impacted, a bridge may prove
preferable. When applicable, DOT should not install the bridge bents in the creek, to the maximum
extent practicable.
11. Sediment and erosion control measures should not be placed in wetlands or streams.
12. Borrow/waste areas should avoid wetlands to the maximum extent practical. Impacts to wetlands in
borrow/waste areas will need to be presented in the 401 Water Quality Certification and could
precipitate compensatory mitigation.
13. The 401 Water Quality Certification application will need to specifically address the proposed
methods for stormwater management. More specifically, stormwater should not be permitted to
discharge directly into streams or surface waters.
lYllr1U41YlVVl.V
f f)ctober X25, 2006
DENR Project # 07-0120
Page 3 of 4
14. Based on the information presented in the document, the magnitude of impacts to wetlands and
streams may require an Individual Permit (IP) application to the Corps of Engineers and
corresponding 401 Water Quality Certification. Please be advised that a 401 Water Quality
Certification requires satisfactory protection of water quality to ensure that water quality standards
are met and no wetland or stream uses are lost. Final permit authorization will require the submittal
of a formal application by the NCDOT and written concurrence from the NCDWQ. Please be
aware that any approval will be contingent on appropriate avoidance and minimization of wetland
and stream impacts to the maximum extent practical, the development of an acceptable stormwater
management plan, and the inclusion of appropriate mitigation plans where appropriate.
15. If concrete is used during construction, a dry work area should be maintained to prevent direct
contact between curing concrete and stream water. Water that inadvertently contacts uncured
concrete should not be discharged to surface waters due to the potential for elevated pH and
possible aquatic life and fish kills.
16. If temporary access.roads or detours are constructed, the site shall be graded to its preconstruction
contours and elevations. Disturbed areas should be seeded or mulched to stabilize the soil and
appropriate native woody species should be planted. When using temporary structures the area
should be cleared but not grubbed. Clearing the area with chain saws, mowers, bush-hogs, or other
mechanized equipment and leaving the stumps and root mat intact allows the area to re-vegetate
naturally and minimizes soil disturbance.
17. Placement of culverts and other structures in waters, streams, and wetlands shall be placed below
the elevation of the streambed by one foot for all culverts with a diameter greater than 48 inches,
and 20 percent of the culvert diameter for culverts having a diameter less than 48 inches, to allow
low flow passage of water and aquatic life. Design and placement of culverts and other structures
including temporary erosion control measures shall not be conducted in a manner that may result in
dis-equilibrium of wetlands or streambeds or banks, adjacent to or upstream and down stream of the
above structures. The applicant is required to provide evidence that the equilibrium is being
maintained if requested in writing by DWQ. If this condition is unable to be met due to bedrock or
other limiting features encountered during construction, please contact the NC DWQ for guidance
on how to proceed and to determine whether or not a permit modification will be required.
18. If multiple pipes or barrels are required, they should be designed to mimic natural stream cross
section as closely as possible including pipes or barrels at flood plain elevation and/or sills where
appropriate. Widening the stream channel should be avoided. Stream channel widening at the inlet
or outlet end of structures typically decreases water velocity causing sediment deposition that
requires increased maintenance and disrupts aquatic life passage.
19. If foundation test borings are necessary; it should be noted in the document. Geotechnical work is
approved under General 401 Certification Number 3494/Nationwide Permit No. 6 for Survey
Activities.
20. Sediment and erosion control measures sufficient to protect water resources must be implemented
and maintained in accordance with the most recent version of North Carolina Sediment and Erosion
Control Planning and Design Manual and the most recent version of NCS000250. .
October 25, 2006
DENR Project # 07-0120
Page 4 of 4
21. All work in or adjacent to stream waters should be conducted in a dry work area. Approved BMP
measures from the most current version of NCDOT Construction and Maintenance Activities
manual such as sandbags, rock berms, cofferdams and other diversion structures should be used to
prevent excavation in flowing water.
22. While the use of National Wetland Inventory (NWI) maps, NC Coastal Region Evaluation of
Wetland Significance (NC-CREWS) maps and soil survey maps are useful tools, their inherent
inaccuracies require that qualified personnel perform onsite wetland delineations prior to permit
approval.
4? A "I
23. Heavy equipment should be operated from the bank rather than in stream channels in order to
minimize sedimentation and reduce the likelihood of introducing other pollutants into streams. This
equipment should be inspected daily and maintained to prevent contamination of surface waters
from leaking fuels, lubricants, hydraulic fluids, or other toxic materials.
24. Riprap should not be placed in the active thalweg channel or placed in the streambed in a manner
that precludes aquatic life passage. Bioengineering boulders or structures should be properly
designed, sized and installed.
25. Riparian vegetation (native trees and shrubs) should be preserved to the maximum extent possible.
Riparian vegetation must be reestablished within the construction limits of the project by the end of
the growing season following completion of construction.
The NCDWQ appreciates the opportunity to provide comments on your project. Should you have any
questions or require any additional information, please contact Sue Homewood at (336) 771-4964.
cc: John Thomas, US Army Corps of Engineers, Raleigh Field Office
Chris Militscher, Environmental Protection Agency
Marla Chambers, NC Wildlife Resources
?40lf,Wetlands Transportation Permitting Unit