NC0004961_Draft cover -2020_20210215

ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
LINDA CULPEPPER
Director
NORTH CAROLINA
Environmental Quality
December 22, 2020
Mr. Paul Draovitch, Senior Vice President
Environmental, Health and Safety
Duke Energy Progress, LLC
Mail Code EC13K
P.O. Box 1006
Charlotte, North Carolina 28201-1006
Subject: Draft NPDES Permit
Permit NC0004961
Riverbend Steam Station
Gaston County
Facility Class I
Dear Mr. Draovitch:
The Division has received your request for a renewal of the subject permit. Please
review this Draft Permit carefully to ensure thorough understanding of the conditions and
requirements it contains.
The Draft Permit contains the following significant changes from your current
permit:
• The following Outfalls have been eliminated from the permit because the flow has
ceased after the ash ponds have been decommissioned and ash removed: 001, 002,
011, 101, 103, 104, 105, 106, 109, 110, 111, and 112.
• There are additional Outfalls that have been eliminated from the permit: 102, 107,
and 108. The seeps that have been assigned these Outfall numbers are still flowing,
but following excavation of the coal ash impoundment, they were found to be
streams. If remediation of these streams is necessary, it will be addressed through
the corrective action plan for the former impoundment or other administrative
process.
• Outfall 002A has been repurposed for the discharge of the treated groundwater.
• Appendix A has been repurposed from Plan for Identification of New Discharges to
the Compliance Boundary Map to be consistent with other Duke permits.
• Chronic toxicity requirements have been transferred from Outfall 002 to Outfall 002A.
cD_EQ?).
NORTH CAROLINA
Qepahnentol Enel.omental Qulry
North Carolina Department of Environmental Quality I Division of Water Resources
512 North Salisbury Street 11617Mail Service Center I Raleigh, North Carolina 27699-1617
919.707.3601

• Groundwater Monitoring Well Construction and Sampling special condition has been
removed from the permit to be consistent with other Duke permits.
• Ash Closure Plan special condition has been removed from the permit due to the
completion of the coal ash excavation.
• Priority Pollutant Analysis condition has been removed from the permit since Outfall
002 is closed.
• Chronic Toxicity Monitoring frequency was reduced from Monthly to Quarterly due to
the completion of the coal ash excavation.
• Ash Settling Basin special condition has been removed from the permit due to the
completion of the coal ash excavation and decommissioning of the coal ash basins.
• Total Copper and Total Iron Monitoring has been removed from the permit since the
facility has been decommissioned and no longer subject to 40 CFR 423.
• The type of sampling for Outfall 002A has been changed from Grab to Composite
based on the requirements of 15A NCAC 2B .0500.
• Monitoring for Arsenic, Selenium, and Mercury have been added to Outfall 002A
based on the permitting policy for coal-fired power plants.
• The Applicable State Law special condition has been removed from the permit due to
the removal of all coal ash from the site.
Please provide any comments you have regarding the draft permit to this office
by January 25, 2021. At this time, the Division is also publishing a notice in the
newspapers of general circulation in Gaston County, inviting public comment on the Draft
Major Modification. Following the 30-day comment period, we will review all pertinent
comments received and take appropriate action on the permit modification.
If you have any questions about the NPDES permit process, please contact me at
the following e-mail address: sergei.chernikovva,ncdenr.gov, or telephone number: 919-707-
3606.
Sincerely,
Sergei Chernikov, Ph.D.
Environmental Engineer III
Industrial NPDES Permitting Unit
cc: Central Files
NPDES Files
EPA Region IV (e-copy)
Mooresville Regional Office/Water Quality (e-copy)
Mooresville Regional Office/PWS (e-copy)
WSS/Aquatic Toxicology Unit (e-copy)
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