R-5911 Avery Co Comments

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ROY COOPER o
Governor
DIONNE DELLFGATTI
Secretary r` n0
S.DANIEL SMITH NORTH CAROLINA
Director Environmental Quality
April 19,2021
MEMORANDUM
To: Lisa Feller,PE(Vaughn&Melton,Inc.)for NCDOT Division 11 [e-mail])
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From: Dave Wanucha,NC Division of Water Resources,Winston Salem Regional Offic -P 4/19/2021
Subject: Scoping comments for proposed R-5911 project(US 19/NC 194 Intersection)in Avery County.
Reference your correspondence dated April 8,2021 in which you requested comments for the referenced project.
Preliminary analysis of the projects reveals the potential for multiple impacts to streams and jurisdictional wetlands
in the project areas. More specifically,impacts to:
• Cranberry and Blevins Creeks;Classification C;Trout;Index No. 8-22-16 and 8-22-16-2;
Watauga River Basin
Further investigations at a higher resolution should be undertaken to verify the presence of other streams and/or
jurisdictional wetlands in the area. If any jurisdictional areas are identified,the Division of Water Resources (DWR)
requests that NCDOT consider the following environmental issues for the proposed project:
Project Comments:
1. Both Cranberry and Blevins Creeks carry a Trout waters of the State supplemental designation. DWR
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 Energy,Mineral,and Land Resources(DMLR)and NC Wildlife Resources
Commission(WRC)requirements. Post-construction stormwater BMPs should,to the maximum extent
practicable(MEP),be selected and designed to reduce total suspended solids(TSS)and avoid a sustained
increase in the receiving water temperature.
2. Design,installation,operation, and maintenance of all sediment and erosion control measures shall be equal
to or exceed the requirements specified in the most recent version of the North Carolina Sediment and
Erosion Control Manual, or for linear transportation projects, the NCDOT Sediment and Erosion Control
Manual. Sedimentation and erosion control designs shall comply with the requirements set forth in 15A
NCAC 0413.0124,Design Standards in Sensitive Watersheds(15A NCAC 02H.0506(b)(3)and(c)(3);GC 4135)
and the most recent version of NCS0000250.
3. All erosion control devices shall be maintained on all construction sites,borrow sites,and waste pile(spoil)
sites,including contractor-owned or leased borrow pits associated with the project. Sufficient materials
required for stabilization and/or repair of erosion control measures and stormwater routing and treatment
shall be always on site.
D E Q�� North Carolina Department of Environmental Quality I Division of Water Resources
512 North Salisbury Street 1 1617 Mail Service Center I Raleigh,North Carolina 27699-1617
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4. For borrow pit sites, the erosion and sediment control measures shall be designed, installed, operated, and
maintained in accordance with the most recent version of the North Carolina Surface Mining Manual.
Reclamation measures and implementation shall comply with the reclamation in accordance with the
requirements of the Sedimentation Pollution Control Act and the Mining Act of 1971.
5. Riparian vegetation(native trees and shrubs)shall 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.
General Comments:
6. Project impacts to wetlands and streams may require a Nationwide(NW)permit 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 DWR. 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.
7. In accordance with the Environmental Management Commission's Rules(15A NCAC 2H.0506[h]),
mitigation will be required for impacts of greater than 300 linear feet to any perennial stream. If mitigation is
required,the mitigation plan shall be designed to replace appropriate lost functions and values. The North
Carolina Division of Mitigation Services(DMS)may be available for assistance with stream mitigation.
8. The NCDOT is respectfully reminded that all impacts,including but not limited to,bridging, fill,excavation
and clearing,and rip rap 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 should one be required.
9. Sediment and erosion control measures should not be placed in wetlands or streams.
10. The 401 Water Quality Certification application will need to specifically address the proposed methods for
stormwater management. More specifically,stormwater shall not be permitted to discharge directly into
streams or surface waters.
11. If concrete is used during construction,a dry work area shall be maintained to prevent direct contact between
curing concrete and stream water. Water that inadvertently contacts uncured concrete shall not be discharged
to surface waters due to the potential for elevated pH and possible aquatic life and fish kills. Concrete shall
be handled in accordance with the NPDES Construction General Permit NCGO 10000.
12. If temporary access roads or detours are constructed,the site shall be graded to its preconstruction contours
and elevations. Disturbed areas shall be seeded or mulched to stabilize the soil and appropriate native woody
species shall be planted. When using temporary structures,the area shall 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.
13. Unless otherwise authorized,placement of culverts and other structures in waters and streams 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 downstream of the above structures. The applicant is
required to provide evidence that the equilibrium is being maintained if requested in writing by the DWR. If
this condition is unable to be met due to bedrock or other limiting features encountered during construction,
please contact the DWR for guidance on how to proceed and to determine whether a permit modification will
be required.

14. If multiple pipes or barrels are required,they shall be designed to mimic natural stream cross section as
closely as possible including pipes or barrels at flood plain elevation,floodplain benches,and/or sills may be
required 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.
15. All work in or adjacent to stream waters shall be conducted in a dry work area. Approved BMP measures
from the most current version of the NCDOT Construction and Maintenance Activities manual such as
sandbags,rock berms,cofferdams and other diversion structures shall be used to prevent excavation in
flowing water.
16. Heavy equipment should be operated from the bank rather than in stream channels to minimize sedimentation
and reduce the likelihood of introducing other pollutants into streams. This equipment shall be inspected
daily and maintained to prevent contamination of surface waters from leaking fuels,lubricants,hydraulic
fluids,or other toxic materials.
17. Riprap shall 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 professionally designed,sized and
installed.
Thank you for requesting our input at this time. The NCDOT is reminded that issuance of a 401 Water Quality
Certification requires that appropriate measures be instituted to ensure that water quality standards are met and
designated uses are not degraded or lost. If you have any questions or require additional information,please contact
Dave Wanucha at(336)403-5655 or [e-mail].
Electronic copy only distribution:
Kevin Hining,NCDOT,Division 11 DEO
Lori Beckwith,USACE,Asheville Office
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