20080540 Ver 1_Staff Comments_20080306

W A T ??QG
March 6, 2008
MEMORANDUM
To Melba McGee, DENR Environmental Coordinator
From Rob Ridings, Division of Water Quality, Transportation Permitting Unit X;e
Subject Comments on the Environmental Assessment related to proposed Triangle Parkway,
Durham & Wake County, Federal Aid Project No NHS-54(7), State Project No
39942 1 TAI, TIP No U-4763B, DENR Clearinghouse No 08-0264
This office has reviewed the referenced document dated received February 28, 2008 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 I
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
Protect Specific Comments.
1 This project is being planned as part of the 404/NEPA Process As a participating team member, the
NCDWQ will continue to work with the team
' r
2 Burdens Creek and Kit Creek are class C, NSW waters of the State DWQ is very concerned with
sediment and erosion impacts that could result from this project DWQ recommends that highly
protective sediment and erosion control BMPs be implemented to reduce the risk of nutrient runoff
to these waters DWQ requests that road design plans provide treatment of the storm water runoff
through best management practices as detailed in the most recent version of NC DWQ Stormwater
Best Management Practices
General Comments:
The permit application shall 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 2H 0506(h), it is preferable to present a mitigation plan with the environmental
documentation Appropriate mitigation plans will be required prior to issuance of a 401 Water
Quality Certification
2 Environmental assessment alternatives shall consider design criteria that reduce the impacts to
streams and wetlands from storm water runoff These alternatives shall 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
No thCarohna
Transportation Permitting Und N On
aturQ«t?
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604
Phone [phone] / FAX [phone] / Internet htto //h2o enr state nc us/ncvvetlands
Michael F Easley, Governor
William G Ross Jr, Secretary
North Carolina Department of Environment and Natural Resources
Coleen Sullins, Director
Division of Water Quality
An Equal Opportunity/Affirmative Acton Employer- 50% Recycled/10% Post Consumer Paper
After the selection of the preferred alternative and prior to an issuance of the 401 Water Quality
Certification, the NC Turnpike Authority 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 { 15A 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
4 In accordance with the Environmental Management Commission's Rules { 15A 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 shall 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
6 DWQ is very concerned with sediment and erosion impacts that could result from this project NC
Turnpike Authority shall address these concerns by describing the potential impacts that may occur
to the aquatic environments and any rmthgating factors that would reduce the impacts
1 7 An analysis of cumulative and secondary impacts anticipated as a result of this project is required
1 The type and detail of analysis shall conform to the NC Division of Water Quality Policy on the r
1 assessment of secondary and cumulative impacts dated April 10, 2004
NC Turnpike Authority 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
9 '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 shall 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
10 Sediment and erosion control measures shall not be placed in wetlands or streams
11 Borrow/waste areas shall 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
12 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
appropriate Widening the stream channel shall 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
21 If foundation test borings are necessary, it shall be noted in the document Geotechmcal work is
approved under General 401 Certification Number 33687/Nationwide Permit No 6 for Survey
Activities
22 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
23 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 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
24 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 onsrte wetland delineations prior to permit
approval
25 Heavy equipment shall 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
26 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 shall be properly designed,
sized and installed
27 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
The NCDWQ appreciates the opportunity to provide comments on your project Shall you have any
questions or require any additional information, please contact Rob Ridings at [phone]
cc Eric Alsmeyer, US Army Corps of Engineers, Raleigh Field Office
Jennifer Hams, PE, NC Turnpike Authority
Gregory J Thorpe, PhD, NCDOT PDEA
Kathy Matthews, Environmental Protection Agency
Travis Wilson, NC Wildlife Resources Commission
File Copy
13 Based on the information presented in the document, the magnitude of impacts to wetlan&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 NC Turnpike Authority 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
14 Bridge supports (bents) shall not be placed in the stream when possible
15 Whenever possible, the DWQ prefers spanning structures Spanning structures usually do not
require work within the stream or grubbing of the streambanks and do not require stream channel
realignment The horizontal and vertical clearances provided by bridges allow for human and
wildlife passage beneath the structure, do not block fish passage and do not block navigation by
canoeists and boaters
16 Bridge deck drains shall not discharge directly into the stream Stormwater shall be directed across
the bridge and pre-treated through site-appropriate means (grassed swales, pre-formed scour holes,
vegetated buffers, etc ) before entering the stream Please refer to the most current version of NC
DWQ Stormwater Best Management Practices
17 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
18 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
19 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
20 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 and/or sills where,