NC0005088_EMC SOC WQS17-009_20191024

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t DUKE James Wells
Vice President
ENERGY®
Environmental,Health and Safety
Programs&Environmental Sciences
526 South Church Street
Charlotte,NC 28202
[phone]
October 24, 2019
Via Overnight Mail
Landon Davidson
Asheville Regional Office Regional Supervisor
North Carolina Department of Environmental Quality
Division of Water Resources
Water Resources - Water Quality Regional Operations
2090 U.S. 70 Highway
Swannanoa, NC 28778-821 1 RECEIVED
Bob Sledge
North Carolina Department of Environmental Quality NOV 04 2019
Water Quality Permitting Program NCDEQ/DU'VR/NPDES
Division of Water Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
Subject: Report Under Special Order by Consent —EMC SOC WQ S 17-009
Duke Energy Carolinas, LLC — Rogers Energy Complex
NPDES Permit NC0005088
Quarterly Progress Report for 3rd Quarter 2019
Dear Messrs. Davidson and Sledge:
On behalf of Duke Energy Carolinas, LLC (DEC), I am submitting to you the Rogers Energy
Complex quarterly progress report that summarizes the work and activities undertaken with respect
to closure of coal ash surface impoundment as required by the Rogers Energy Complex NPDES
Permit NC0005088 Special Order by Consent (SOC), SOC No. S 17-009 Section 2.c.2).
As required by the SOC, I certify under penalty of law that this document and all attachments were
prepared under my direction or supervision in accordance with a system designed to assure that
qualified personnel properly gather and evaluate the information submitted. Based on my inquiry
of the person or persons who manage the system, or those persons directly responsible for
gathering the information, the information submitted is, to the best of my knowledge and belief,
true, accurate, and complete. I am aware that there are significant penalties for submitting false
information, including the possibility of fine and imprisonment for knowing violations.
L

Messrs. Davidson and Sledge
October 24, 2019
Page 2
Please direct any questions concerning the Rogers Energy Complex NPDES Permit NC0005088
SOC No. S 17-009 to Robert Wylie at [phone].
Sincerely,
Jame Wells
Vice President, Environment, Health & Safety-
Programs and Environmental Sciences
Duke Energy
Attachment:
Rogers Energy Complex Quarterly Progress Report
cc: Richard Baker, Duke Energy
Robert Wylie, Duke Energy
Steve Hodges, Duke Energy
George Hamrick, Duke Energy
Paul Draovitch, Duke Energy
Matt Hanchey, Duke Energy
Randy Hart, Duke Energy
L

NPDES PERMIT NC0005088
SPECIAL ORDER BY CONSENT EMC SOC S17-009
QUARTERLY PROGRESS REPORT
ROGERS ENERGY COMPLEX (CLIFFSIDE STEAM STATION)
OCTOBER 24, 2019

Background and Summary
On April 18, 2018, Duke Energy Carolinas, LLC (DEC) and the North Carolina Environmental Management
Commission entered into a Special Order by Consent — EMC SOC 517-009 (SOC) applicable to the Rogers
Energy Complex(Rogers), also known as the Cliffside Steam Station. This report is submitted in accordance
with Section 2.c.2) of the SOC. In compliance with Section 2.c.2), this report summarizes the work and
activities undertaken with respect to decanting work and closure of coal ash surface impoundments at
Rogers. The quarterly reports are due no later than the last day of January, April, July, and October for the
duration of the SOC, once the decanting process has begun.
The Rogers Energy Complex is located in Mooresboro, North Carolina. The Station is located on the south
side of the Broad River approximately 55 miles west of Charlotte and about 1.5 miles south of the Town of
Cliffside, North Carolina. The power plant straddles the Cleveland and Rutherford County line. The Station
began construction and initial operation in 1939 and 1940 with Units 1-4. Unit 5 began operation in 1972,
followed by Unit 6 in 2012. Units 1-4 were retired from service in October 2011, as part of the Station
decommissioning and demolition program, and the Units 1-4 building was imploded in October 2015.
Units 5 and 6 continue to operate with a combined capacity of approximately 1387 megawatts.
The Station's ash management facilities include the Unit 5 Inactive Ash Basin, the Active Ash Basin, which
includes an ash stack area,Ash Storage Area 1, and the on-site landfill. The ash in the Units 1-4 Ash Basin has
been excavated and placed in the on-site landfill, and this area has been repurposed for stormwater and
plant process wastewater basins. Discharge from the Active Ash Basin is permitted by the NCDEQ Division of
Water Resources under the National Pollutant Discharge Elimination System Permit NC0005088.
The Active Ash Basin is located on the eastern portion of the site, east and southeast of Unit 5 and Unit 6.
This Basin began receiving sluiced ash from Unit 5 in 1975 and continued to receive fly ash until October 2017
and sluiced bottom ash until May 2018 from Unit 5 when a conversion was completed to enable dry handling
of ash. The current ash inventory of the Active Ash Basin is 5.0 million tons as of July 30, 2019.
Decanting Status
In compliance with this SOC, Duke Energy initiated design and procurement efforts in Q3 2018 for a decanting
water treatment system at Rogers. Purchase Orders were awarded in Q4 2018 for the civil pad and electrical
infrastructure installations, as well as a Purchase Order for the OEM water treatment supplier. Duke Energy
completed installation and commissioning of the decanting water treatment system on January 25, 2019 and
commenced decanting by gravity discharge following removal of plant operational flows on March 31, 2019.
Duke Energy provided advance notice for the projected start date of decanting to NCDEQ on March 15, 2019,
as required by the NPDES Permit, and written notification for the Initiation of Decanting per the SOC on
April 8, 2019. Through September 30, 2019, approximately 13.9 feet have been decanted from an initial
depth of 45 feet.
Due to the sloughing event that occurred at Cliffside on July 1, 2019, decanting ceased during the period July
1,2019 through August 1, 2019. This resulted in a loss of the ability to lower the basin by approximately four
feet during this timeframe. This event, along with limits on the decanting rate, which is currently one foot
per week, could potentially affect the Station's ability to meet its decanting date.
Rogers: 1