NC0003425_Startup of new FGD Treatment Components_20191106

(� DUKE
ENERGY
RECEIVED
NOV 0 7 7019
November 6, 2019 NCDEQIDWRINPDES
Ms. Sheila Holman
Assistant Secretary
NC Department of Environmental Quality
217 West Jones Street
Raleigh, NC 27603
Subject: Startup of new FGD treatment components
Internal process flow modifications
Roxboro Steam Electric Plant
NC0003425
Person County
Dear Assistant Secretary Holman,
Paul Draovitch, P.E.
Senior Vice President
Environmental, Health & Safety
and Operations Support
526 S. Church Streel
Mail Code: EC3XP
Charlotte, NC 28202
[phone]
This letter is to provilt'e details and notice about the planned startup of required treatment
components at the subject facility. Duke Energy has constructed a new wastewater system to
replace the existing system used to treat flue gas desulfurization (FGD) wastewater since 2008.
Details of this new system were shared with the Department in an application submittal dated
August 15, 2016. That submittal is enclosed with this letter for ease of reference. Much of the
existing system sits within the footprint of the west ash basin which will be closed resulting in
the need for the new system.
Duke Energy intends to commence commissioning activities for the new FGD wastewater
system and place it into service after concurrence from your agency. Commissioning is expected
to take between 6-8 weeks with tuning of the system taking up to 6 months to reach optimum
treatment efficiencies of the biological system. As indicated in the 2016 submittal, flows from
the new FGD wastewater treatment system will be directed to the lined retention basin for
commingling with other wastewater sources and then to outfa11003, the same discharge point
where current flows are directed. The internal flow path from the lined retention basin is
currently in use as approved by the Department earlier this year.
As described in the 2016 submittal, there will be a period where flows from both the old and new
FGD wastewater treatment, system occur as the old system processes remaining flow in the FGD
settling basin until that system is closed. Duke Energy -will continue to properly operate the old
system and will sample as required while that system continues to function.
www.duke-energy.com

Ms. Sheila Holman
Roxboro FGD startup concurrence request
November 6, 2019
Duke will sample the new FGD treatment system in accordance with the existing permit
requirements associated with outfall 010. These sample results will be reported as an attachment
to our monthly required NPDES Discharge monitoring report much like our lined retention basin
samples are currently reported.
Duke Energy hereby requests your concurrence with this action with the understanding
that this action is being taken under the conditions of the existing permit and is not
intended in any way to be binding on the future permitting decisions or terms currently
under review by the Department.
If there are any questions about this matter please contact Mr. Shannon Langley at (919) 546-
2439 or [e-mail].
Sincer ly,
Paul Draovitch
Senior Vice President,
Environmental, Health & Safety and Operations Support
Duke Energy
Enclosure
cc: RRO DEQ WQ Supervisor w/enclosure
3800 Barrett Drive
Raleigh, NC 27609
Jeff Poupart — DWQ Section Chief w/enclosure
1617 Mail Service Center
Raleigh, NC 27699-1617
Lori Tollie - via email
Shannon Langley — via email