20150610 Ver 3_USACE Correspondence_20170712

Regulatory Division/1200A
Action ID: SAW -2015-01381
DEPARTMENT OF THE ARMY
WILMINGTON DISTRICT, CORPS OF ENGINEERS
69 DARLINGTON AVENUE
WILMINGTON, NORTH CAROLINA 28403-1343
July 12, 2017
Mr. Steve Cahoon
Duke Energy Environmental Services Department
410 South Wilmington Street
Raleigh, North Carolina 27601
Dear Mr. Cahoon:
Please reference your Individual Permit application, dated April 28, 2017, for Department of
the Army (DA) authorization to permanently discharge fill material into 624 linear feet of stream
channel and 2.3 acre of riparian, non-riverine wetlands, associated with activities related to the
excavation and disposal of coal combustion residual (CCR) materials from areas of coal ash fill
at the Duke Energy Dan River Steam Station. The proposed project area is located at the Duke
Energy Dan River Steam Station property, south and east of South Edgewood Road, and north of
the Dan River, in Eden, Rockingham County, North Carolina
The U.S. Army Corps of Engineers, Wilmington District (Corps) advertised your proposal by
public notice dated May 12, 2017. Comments in response to the notice were received from the
NC Department of Cultural Resources (NCDCR), NC Wildlife Resources Commission
(NCWRC), and the NC Division of Water Resources (NCDWR). The comments received are
enclosed for your information and to provide you with the opportunity to address any of the
stated concerns, if you have not already done so. Please note that the NCDCR, in a letter dated
June 8, 2017, stated that they are aware of no historic resources which would be affected by the
project, and therefore they have no comment on the project as proposed.
On February 6, 1990, the Department of the Army (DA) and the U.S. Environmental
Protection Agency (EPA) signed a memorandum of agreement (MOA) establishing procedures
to determine the type and level of mitigation necessary to comply with Clean Water Act (CWA)
Section 404(b)(1) Guidelines. This MOA provides for first, avoiding impacts to waters and
wetlands through the selection of the least damaging, practical alternative; second, taking
appropriate and practical steps to reduce impacts on waters and wetlands; and finally,
compensation for remaining unavoidable impacts to the extent appropriate and practical. To
enable us to process your application, in compliance with the MOA, we request that you provide
the following additional information:

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a. Permits for work within wetlands or other special aquatic sites are available only if
the proposed work is the least environmentally damaging, practicable alternative.
Please furnish information regarding any other alternatives, including upland
alternatives, to the work for which you have applied and provide justification that
your selected plan is the least damaging to water or wetland areas.
1) Your permit application includes three alternative for the Stormwater
Diversion Project, including using a 400 gallon per minute (gpm) Pump -
around, a 49,000 gpm High -volumetric Flow Rate Pump -around, and
Gravity flow. However, during our February 17, 2017 pre -application
meeting we discussed including a fourth alternative using a reasonable
"in-between" flow rate pump -around alternative. The goal of this
alternative would be to evaluate any reductions in over -flooding impacts
to wetlands and streams proposed associated with the upland flow area
(UFA). Please include this alternative as discussed, specifically with
regard to practicability per 40 CPR § 230.10a.
b. It is necessary for you to have taken all appropriate and practicable steps to minimize
losses of waters of the U.S., including wetlands. Please indicate all that you have
done, especially regarding development and modification of plans and proposed
construction techniques, to minimize adverse impacts. Specifically:
1) Your permit application includes avoidance and minimization information
and is generally sufficient for continued evaluation.
c. The MOA requires that appropriate and practicable mitigation will be required for all
unavoidable adverse impacts remaining after the applicant has employed all
appropriate and practicable minimization. Please indicate your plan to mitigate for the
projected, unavoidable loss of waters or wetlands or provide information as to the
absence of any such appropriate and practicable measures.
1) Please provide the mitigation acceptance letter from the NC Division of
Mitigation Services (NCDMS). Please note that Wetlands A and the
Dredge Basin wetland would both classify as Headwater Forest wetlands
per the NC Wetland Assessment Method (NCWAM) Dichotomous Key,
despite the downslope fills developed as part of earlier development
operations at the Dan River Steam Station. This determination was made
given that both of these wetland systems occur within natural topographic
crenulations without streams. The Corps considers Headwater Forest
wetlands to fit the wetland mitigation credit classification of Riparian,
Non-Riverine wetlands rather than Non -Riparian wetlands. Please clarify
your wetland mitigation proposal based on the above.

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Additionally, the following items must be resolved prior to continuing to process your permit
request:
1) Given that one or both of the temporary stream crossings authorized under SAW -2016-
00331 have experienced recent damage due to high flow events, and at least one of these
crossings will be removed pending authorization of a permanent crossing, please provide
culvert pipe plans/details for these crossings described as part of the DR 134 project.
Note that, unless otherwise justified, these permanent crossings must abide by
Nationwide Permit Regional Condition 3.6 issued March 16, 2017. Further, it appears
that Figure 02 "Dan River Steam Station DR -131 Project Impact Area" does not comply
with Regional Condition 3.6.1 as the pipe is perched above the existing stream bed.
Lastly, given recent high flow events, please evaluate up-sizing the proposed culvert pipe
diameter or increasing the number of culvert pipes placed at each crossing.
The aforementioned requested information is essential to the expeditious processing of your
application; please forward this information to us within 30 days of your receipt of this letter. If
you have any questions regarding these matters, please contact me at [phone] extension
30 or David.E.Bailey2 a,usace.arm y}mil.
Sincerely,
David E. Bailey
Regulatory Project Manager
Raleigh Field Office
Copies furnished with enclosure:
Mr. Richard Harmon
Amec Foster Wheeler Environment and Infrastructure, Inc.
4021 Stirrup Creek Drive, Suite 100
Durham, North Carolina 27703

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Copies furnished without enclosure:
Mr. Todd Bowers
Permit Review Specialist
Wetlands Regulatory Section
U.S. Environmental Protection Agency - Region IV
Sam Nunn Atlanta Federal Center
61 Forsyth Street, SW
Atlanta, Georgia 30303
Ms. Daren Higgins
NCDENR — Division of Water Resources
Water Quality Programs
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Ms. Sue Homewood
Division of Water Resources
NCDENR — Division of Water Resources
450 West Hanes Mill Road, Suite 300
Winston Salem, North Carolina 27105

®North Carolina Wildlife Resources Commission
Gordon Myers, Executive Director
MEMORANDUM
TO: Richard Harmon
Amec Foster Wheeler Environmental & Infrastructure, hre.
FROM: Olivia Munzer y
Western Piedmont Coordinator
Habitat Conservation
DATE: 12 June 2017
SUBJECT: Individual Permit Application for the Duke Energy Dan River Steam Station Stormwater
Diversion Project and Associated Projects; Rockingham County; DEQ Project No.
201506100.
Biologists with the North Carolina Wildlife Resources Commission (NCWRC) have reviewed the subject
documents. Comments are provided in accordance with provisions of the Clean Water Act of 1977 (as
amended) and Fish and Wildlife Coordination Act Wildlife Coordination Act (48 Stat. 401, as amended;
16 U.S.C. 661 et seq.).
On behalf of Duke Energy, Amec Foster Wheeler Environment & Infrastructure, Inc. has submitted an
Individual Permit application for the stormwater diversion project and other previously permitted projects
(SAW -2016-00331, SAW -2014-01477, and SAW -2015-01670) at the Dan River Steam Station located
southeast of Eden, Rockingham County, North Carolina (N.C.). Impacts to stream and wetlands for the
stormwater diversion project previously permitted projects, including prior work activities, total 1137
linear feet Of) of streams, 1.89 acres of a dredge basin, and 0.915 acres of wetlands. Duke Energy
proposes to pay into the N.C. Division of Mitigation Services hi -Lieu Fees Program to offset impacts at a
mitigation ratio of 2:1 for 11371f of perennial stream; a 1:1 ratio for 1.89 acres of dredge basin impacts; a
2:1 ratio for 0.597 acres of non -riparian wetland impacts; and 2:1 ratio for 0.318 acres of riparian wetland
impacts.
Unnamed tributaries to the Dan River flow through the site and the Dan River borders the southern side of
the site. Dan River occurs in the Roanoke River basin and is classified as a Class C stream by N.C.
Division of Water Resources (NCDWR). The Dan River is designated as the Dan River Aquatic Habitat
Natural Heritage Natural Area.
We have records of the federal and state endangered Roanoke logperch (Pereina rex) and James
spinymussel (Pleurobensa collina); federal species of concern and state significantly rare Roanoke bass
(Ambloplites cavifrons); federal species of concern and state endangered green floater (Lasmigona
Mailing Address: Habitat Conservation Division ^ 1721 Mail Service Center • Raleigh, NC 27699-1721
Telephone: [phone] ^ Fax: [phone]

Page 2
12 June 2017
Dan River Steam Station
DEQ Project No. 201506100
subviridis) and yellow lampmussel (Lampsilis cariosa); state threatened bigeye jumprock (Moxostoma
ariommum); state significantly rare quillback (Carpoides cyprinus); and state special concern riverweed
darter (Etheostoma podostemone) in the Dan River within the vicinity of the site. The United States Fish
and Wildlife Service (USFWS) also lists the smooth coneflower (Echinacea Iaevigata), a federally and
state endangered species, as having the potential to occur at the site; however, smooth coneflower was not
found during surveys of the site.
We have no objections to the project; however, we offer the following recommendations to minimize
impacts to aquatic and terrestrial wildlife resources.
1. Due to the presence of protected species in the Dan River, ensure off-site stormwater does not
contact other contaminated water or coal combustion residue fi•om the site and is routed around
the site. All discharges into the Dan River or its tributaries should comply with NPDES permit
requirements.
2. Culverts should be designed to provide aquatic life passage. Culverts or pipes should be buried at
least one foot or 20% of their size below the natural streambed (measured from the natural
thalweg depth). Aquatic life passage should be assured during low flow or drought conditions.
Any riprap used should not interfere with aquatic life movement during low flow.
3. Native vegetation and bioengineered structures should be used for stream stabilization where
possible. Riprap used for stream bank stabilization should be limited to the stream bank below
the high-water mark, and vegetation should be used for stabilization above the high-water mark.
Long-term stabilization can be accomplished using native plants such as red maple, black willow,
sycamore, river birch, silky dogwood, and other native woody species. Riprap should not be
placed in the stream bed.
4. Re -seed disturbed areas with seed mixtures that are beneficial to wildlife. Avoid fescue -based
mixtures because fescue is invasive and provides little benefit to wildlife. Using native species
instead of ornamentals should reduce the need for water, fertilizers, and pesticides. Further
information and free technical guidance from NCWRC is available upon request.
5. Sediment and erosion control measures should use advanced methods and installed prior to any
land -disturbing activity. The use of biodegradable and wildlife -friendly sediment and erosion
control devices is strongly recommended. Silt fencing, fiber rolls and/or other products should
have loose -weave netting that is made of natural fiber materials with movable joints between the
vertical and horizontal twines. Silt fencing that has been reinforced with plastic or metal mesh
should be avoided as it impedes the movement of terrestrial wildlife species. Excessive silt and
sediment loads can have detrimental effects on aquatic resources including destruction of
spawning habitat, suffocation of eggs, and clogging of gills.
Thank you for the opportunity to review and comment on this project. If I can be of further assistance,
please contact me at [phone] or [e-mail].
ncwildlife.ore.
ec: Sue Homewood, NCDWR
David Bailey, USACE
Byron Hamstead, U.S. Fish and Wildlife Service
Steve Cahoon, Duke Energy

North Carolina Department of Natural and Cultural Resources
State Historic Preservation Office
Ramona M. Bartos, Administrator
Governor Roy Cooper
Secretary Susi H. Hamilton
June 8, 2017
David Bailey
Raleigh Regulatory Field Office
3331 Heritage Trade Drive, Suite 105
Wake Forest, NC 27587
office of Archives and History
Deputy Secretary Kevin Cherry
Re: Wetland Impacts for the Excavation and Disposal of Coal Combustion Residual Materials at
Duke Energy Dan River Steam Station, SAW 2015-01381, Rockingham County, ER 17-0926
Dear Mr. Bailey:
We have received a public notice concerning the above project.
We have conducted a review of the project and are aware of no historic resources which would be affected
by the project. Therefore, we have no comment on the project as proposed.
The above comments are made pursuant to Section 106 of the National Historic Preservation Act and the
Advisory Council on Historic Preservation's Regulations for Compliance with Section 106 codified at 36
CPR Part 800.
Thank you for your cooperation and consideration. If you have questions concerning the above comment,
contact Renee Gledhill -Earley, environmental review coordinator, at 919-807-6579 or
[e-mail]. In all future communication concerning this project, please cite the
above referenced tracking number.
Sincerely,y,
�Vkamona M. Bartos
Location: 109 Fast Jones Street, Raleigh NC 27601 Mailing Address: 4617 Mail Service Center, Raleigh NC 27699-4617 Telephone/Fox:(919)807-65701807-6599

Water Resources
Environmental Quality
June 1, 2017
Duke Power Company
Attn: Steve Cahoon
411 Fayetteville St
Mail Code: NC14
Raleigh. NC 28601
ROY COOPER
Governor
MICHAEL S. REGAN
Seerefnry
S. JAY ZHVE\4ERMAN
Dtrecfa•
D W R # 15-0610 v3
Rockingham County
Subject: REQUEST FOR ADDITIONAL INFORMATION
Dan River Steam Station Stormwater Diversion Project and associated Projects
Dear Mr. Cahoon:
On May 2, 2017, the Division of Water Resources — Water Quality Programs (Division) received your
application dated April 28, 2017, requesting an Individual 401 Water Quality Certification from the Division
for your project. The Division has determined that your application is incomplete and cannot be
processed.. The application is being placed on -hold until all of the following information is received:
1. This project includes a revision to impacts previously approved by the Division on May 12, 2016
(DWR#2016-0156v2). These impacts were for an access road for the Dan River Scarp Repair and
were approved as temporary impacts. The current application for an Individual Permit requests
that these impacts be approved as permanent impacts. The original review by the Division was
based on temporary impacts and therefore the Division requires a more detailed analysis of the
purpose and need for permanent impacts as well as a more detailed analysis of avoidance and
minimization measures. In addition, this project will be placed on hold until a compliance
inspection of these culverts has been conducted. [15A NCAC 02H .0506(f) and (g)]
2. Your application indicates that 130 linear feet of stream stabilization will occur at location DR -134
however Plan Sheet DR -134 Section Detail, Figure 02 shows rlprap shading throughout the entire
channel bed. Please clarify whether riprap will be extended throughout the channel bed.
3. As requested in the pre -application, please provide a detailed analysis of the velocity expected at
outfall SW010, the riprap pad specifications and details, and an analysis of the impact this
additional flow and velocity may have on wetlands that are present Immediately downslope of this
area.
State of North Carolina I Environmental Quality
450 W. Hanes Mill Road, Suite 300, Winston-Salem, North Carolina 27105
Phone: [phone] FAX: [phone]

Duke Energy
DWR# 2015-0610 v2
Request for Additional Information
Page 2 of 2
Pursuant to Title 15A NCAC 02H .0502(e), the applicant shall furnish all of the above requested information
for the proper consideration of the application. If all of the requested information is not received in writing
within 30 calendar days of receipt of this letter, the Division will be unable to approve the application and it
will be returned. The return of this project will necessitate reapplication to the Division for approval,
including a complete application package and the appropriate fee.
Please respond in writing within 30 calendar days of receipt of this letter by sending two copies of all of the
above requested information to the 401 & Buffer Permitting Unit, 1650 Mail Service Center, Raleigh, NC
27699-1650.
Please be aware that you have no authorization under the Water Quality Certification Rules for this activity
and any work done within waters of the state may be a violation of North Carolina General Statutes and
Administrative Code.
Please contact me at 336-776-9693 or Sue. [e-mail] if you have any questions or concerns.
Sincerely,
S��- -"S�'
Sue Homewood
Winston-Salem Regional Office
cc: Julia Tillery, Amec Foster Wheeler Environment & Infrastructure Inc. (via email)
David Bailey, USACE Raleigh Regulatory Field Office (via email)
DWR WSRO 401 files
DWR 401 & Buffer Permitting Unit