NC0000396_Notice of Pending Wastewater Facility_20160208

16DUKEHarry K.Sideris
Senior Vice President
ENERGY, Environmental, Health&Safety
526 S. Church Street
Mail Code:EC3XF
Charlotte, NC 28202
[phone]
February 1, 2016
Mr.Jeff Poupart. Section Chief RECEIVED/NCDEQIDWR
NCDEQ, Division of Water Resources
1617 Mail Service Center FEB 0 8 2016
Raleigh, NC 27699-1617
Water Quality
Subjects: Asheville Steam Electric Plant Permitting Section
Notice of Pending Wastewater Facility Revision
Buncombe County
NC0000396
Dear Mr. Poupart,
Duke Energy Progress, LLC (Duke) is providing notice that the small open water area of the
1964 basin (hereinafter referred to as the "Duck Pond") will be repurposed to provide
stormwater treatment and its current function of treating process wastewater transferred to a new
Rim Ditch filter system. In March of 2013, staff from Duke's Environmental Services group met
with staff of the Division's Asheville regional office and discussed plans to construct a lined
"rim ditch" within the footprint of the 1964 ash basin to facilitate continued ash reclamation
from the 1982 ash basin. As discussed and documented on drawings provided to the Division,
flows from that rim ditch were directed to the "Duck Pond" as an added measure of treatment.
Continued progress towards excavation of the ash basins in accordance with the North Carolina
Coal Ash Management Act of 2014 necessitates that Duke redirect wastewater flows from the
"Duck pond" to a new filter system.
Upon removal of the Duck Pond from service, to assure compliance with the permit, the
treatment of the waste water previously provided by retention in the "Duck Pond" will be
provided by a series of 25 micron filters. The feed for the filters will be from the secondary
basin, near the current overflow point, and the effluent will feed back into the current
conveyance system, downstream of the Duck Pond.
The effluent from the filters will be directed into the existing discharge pipe leading to the
stilling basin and ultimately to outfall 001. Upon completion of the Filter system, the former
Duck Pond settling basin area will be utilized, as it was originally, as a collection point for
stormwater runoff. Stormwater collected in the "Duck Pond" will be directed to the Rim Ditch
for treatment, ultimately discharging at outfall 001.
This letter serves as notification of the upcoming cessation of treatment provided by the Duke
Pond and replacement of that treatment function by the filter system. As the movement of the
wastewater will be conducted within the same treatment system, there are no new flows being
added and there is no change to the final release point of this water. It is Duke 's position that

Mr. Jeff Poupart
Page 2
this activity does not require an NPDES permit modification of other water permitting actions. It
is also Duke's position that this activity is not substantively different from the activities deemed
covered by existing permits in the attached letters dated April 6, 2015 and October 23, 2015. Duke
requests confirmation of this position for our files.
If there are any questions regarding the enclosed information, please contact Tina Woodward at
(704) 382- 4585 or [e-mail].
Sincerely,
/4-.0
Harry K. Sideris
SVP, Environmental Health and Safety
Enclosure
cc: Central Files
NPDES Files
ARO
Teresa Williams - Asheville Plant
Landon Davidson

DUKE HanyK Sideris
ENERGY. senor Vice President
Environmental,Health 6 Safety
526 S.Church Street
Mall Code'EC3XP
Charlotte,NC 28202
(704)3824303
April 6, 2015
Mr. Jeff Poupart
North Carolina Division of Water Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
Subject: Duke Energy Facilities
Movement of water and solids within a
wastewater treatment system
Mr. Poupart,
As you recently discussed with technical staff from Duke Energy's (Duke)
Environmental Services staff, this letter provides a summary of our understanding of
handling wastewater solids and wastewater within a wastewater treatment system.
As background information, a number of, but not all, NPDES permits held by Duke in
North Carolina contain the following statement:
"During the term of the permit, the permittee shall remove settled material from
the ponds or otherwise enlarge the available storage capacities in order to
maintain the required minimum volumes at all times."
As you know, the ash basins at our North Carolina facilities are permitted wastewater
treatment systems that can range from approximately 50 acres in surface area to over
400 acres. At a number of our generation plants, there are multiple treatment basins.
Some of these sites have basins that are located "in series" to provide increased
removal of solids. In order to allow for increased capacity for treatment in the form of
residence time and settling capacity Duke has historically moved water and/or solids
from one basin to another or from one area of a basin to another area within the basin.
This movement of water and settled solids may be achieved by dredging and/or
pumping wastewater and/or solids from one basin to another. Wastewater and/or solids
may be moved by dredging or trucking from one area to another within the same basin.
Duke has long held, with NCDENR knowledge and concurrence, that the activity of
handling solids to increase capacity within an ash basin system in order to provide
adequate treatment and maintain compliance with NPDES permit limits is not only
prudent but required as an authorized practice. At several of our retired sites there is an
added benefit from this activity as it allows for reduction of the phreatic surface within
the ash basin dam therefore increasing the safety factor of the darn. Any reduction of

Mr.Jeffrey Poupart
April 2, 2015
water levels within the treatment system would be done in accordance with Dam Safety
guidelines and requirements.
Therefore, it is our understanding based on previous discussions with you and your staff
that there is no requirement for express written permission or any permit modification to
move solids and or wastewater within an ash basin. Additionally, it is Duke's
understanding that no written permission or permit modification is required to allow
movement of wastewater and/or solids, via dredging, between basins within the same
treatment system.
Duke is proceeding with work at various sites based on this understanding. Please
contact me if you have any questions.
Sincerely,
m'31-1------)c--
Harry
Harry K. Sideris
SVP Environmental Health and Safety

North Carolina Department of Environmental Quality
Pat McCrory
Donald R.van der Vaart
Governor Secretary
October 23,2015
Mr. Harry Sideris, Senior Vice President
Environmental, Health and Safety
Duke Energy Carolinas, LLC
Mail Code EC13K
P.O. Box 1006
Charlotte, North Carolina 28201-1006
Subject: Movement of Wastewater Residuals
Permit NC0000396
Asheville Steam Electric Plant
Buncombe County
Dear Mr.Sideris,
The Division has received your letter of October 6,2015 requesting clarification that the movement of ash by
truck between the ash ponds at the Asheville Steam Electric Plant is allowed. The Division maintains that
this activity is authorized by the existing NPDES.wastewater permit provided that all the terms and
conditions of the permit are being met and the water quality standards in the receiving stream are not
contravened. The movement of ash between ponds by truck at other facilities would be allowed under issued
NPDES permits but may be subject to stormwater permitting requirements. You should consider consulting
with Bradley Bennett of DEMLR staff at brad.ev-bennettancdenr-qov or telephone number: 919-807-6378 if you
have questions regarding stormwater applicability at other sites.
if you have any questions,please feel free to contact me at the following e-mail address:
jeff.poupartea ncdenr.gov or telephone number:919-807-6309.
Sincerely,
Jeff
Poupart
Water Quality Permitting Chief
Division of Water Resources
cc: Central Files
EPA Region IV(e-copy)
Asheville Regional Office / Water Resources(e-copy)
Linda Culpepper(e-copy)
1601 Mail Service Cenler,Raleigh,North Carolina 27699 1601
Phone [phone] Inlemet www ncdenr gov
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