NC0003425_Report_20200724

(> DUKE
ENERGY
July 24, 2020
Via Overnight Mail
S. Daniel Smith
Director of Water Resources
North Carolina Department of Environmental Quality
1617 Mail Service Center
Raleigh, NC 27699-1617
Bob Sledge
Division of Water Resources
North Carolina Department of Environmental Quality
1617 Mail Service Center
Raleigh, NC 27699-1617
James Wells
Vice President
Environmental, Health and Safety
Programs & Environmental Sciences
526 South Church Street
Charlotte, NC 28202
[phone]
Subject: Report Under Special Order by Consent — EMC SOC WQ S 18-005
Duke Energy Progress, LLC — Roxboro Steam Electric Plant
NPDES Permit NC0003425
Quarterly Progress Report for 2nd Quarter 2020
Dear Mr. Smith and Mr. Sledge:
RECEIVED
.JUt 2 7 2020
11C11EQ/DWR/NPDES
On behalf of Duke Energy Progress, LLC (DEP), I am submitting to you the Roxboro Steam
Electric Plant Progress Report summarizing the work and activities undertaken with respect to
closure of coal ash surface impoundments as required Special Order by Consent (SOC), SOC No.
S 18-005 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.

Mr. Smith and Mr. Sledge
July 24, 2020
Page 2
Please direct any questions concerning the Roxboro Steam Electric Plant SOC No. S 18-005 to
Lori Tollie at [phone].
Sincerely,
James Wells
Vice President, Environment, Health & Safety
Programs and Environmental Sciences
Duke Energy
Attachment:
Roxboro Steam Electric Plant Quarterly Progress Report
CC: Richard Baker, Duke Energy
Lori Tollie, Duke Energy
Robert Howard, Duke Energy
Paul Draovitch, Duke Energy
Matt Hanchey, Duke Energy
Shannon Langley, Duke Energy
Randy Hart, Duke Energy

NPDES PERMIT NC0003425
SPECIAL ORDER BY CONSENT EMC SOC S18-005
QUARTERLY PROGRESS REPORT
ROXBORO STEAM ELECTRIC PLANT
J U LY 24, 2020

Background and Summary
On August 16, 2018, Duke Energy Progress, LLC (DEP) and the North Carolina Environmental Management
Commission entered into a Special Order by Consent - EMC SOC 518-005 (SOC) applicable to the Roxboro Steam
Electric Plant (Roxboro). 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 Roxboro. 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 Roxboro Steam Electric Plant is located in Semora, NC (Person County), on Hyco Lake. Hyco Lake is a man-made
reservoir constructed by the impoundment of the Hyco River. Roxboro is a four -unit, 2422 megawatts, coal-fired
generating facility. Roxboro began commercial operation in 1966, with additions in 1973 and 1980.
Roxboro's ash basin system has two impoundments, which are regulated by the North Carolina Department of
Environmental Quality (NCDEQ): The West Ash Basin and the East Ash Basin. The West Ash Basin is approximately
225 acres and contains nearly 13.0 million tons of coal ash, while the East Ash Basin is approximately 71 (excluding
the limits of the landfill) acres and contains 7.1 million tons of coal ash. Therefore, the ash basin system covers nearly
300 acres with a current ash inventory of approximately 20 million tons of ash, as of February 2020.
Excavation of the Roxboro Flue Gas Desulfurization (FGD) Ponds began on April 6, 2020 and is ongoing. During the
period April 6, 2020 - June 30, 2020, Roxboro excavated 52,827 tons of ash.
Per the Consent Order, signed on February 5, 2020 by NC Superior Court Judge Ridgeway, the ash that is located
beneath the East Ash Basin landfill, approximately 3.9 million tons, is not required to be excavated. Therefore, nearly
16.9 million tons will be excavated. The Roxboro Closure Plan, per the Consent Order, is pending approval with NC
DEQ.
Roxboro historically wet sluiced coal combustion residual (CCR) products into surface impoundments located on the
property. These surface impoundments are known as the East and West Ash Basins. The East Basin became inactive
in 1986 when the West Basin was placed in service. The Basins are impounded by the following dams:
• Inactive (East) Ash Basin (PERSO-033)
• Active (West) Ash Basin (PERSO-038 and PERSO-039)
The Active (West) Ash Basin received CCR products from its initial operation in 1973 until 2019, when wet sluicing of
bottom ash ceased. In the mid-1980s, Roxboro replaced its routine fly ash wet sluicing operation with a dry ash
handling system and began placing dry fly ash into a landfill. Roxboro ceased wet sluicing of bottom ash to the West
Ash Basin in April 2019 when the dry bottom ash system became operational. The Active (West) Ash Basin was
removed from service in April 2019 upon the completion of dry bottom ash handling and diversion of all other
wastewater flow to a newly lined retention basin.
Decanting Status
In compliance with this SOC, Duke Energy initiated design and procurement efforts in Q3 2018 for a decanting water
treatment system at Roxboro. Construction of the infrastructure and water treatment system commenced in Q1
2019, and the system was commissioned and ready for operation in June 2019. Duke Energy planned to commence
mechanical decanting and treatment, once it received a revised NPDESpermit. However, wastewater flows from

the station were removed from the ash basin on April 10, 2019. With the removal of flows to the basin, except for
stormwater, natural decanting commenced and the water level within the area of the basin, north of the internal
filter dike, lowered approximately 13 feet (in excess of 90-million gallons) from its normal operational level to an
approximate elevation of 447 feet, which is equalized with the water level north of the filter dike. Therefore,
decanting is complete, as discussed with NC DWR staff and documented in the Notification from Duke Energy
to the North Carolina Division of Water Resources, regarding EMC SOC 518-005, dated February 11, 2020. Duke
Energy received the new NPDES Permit for the Roxboro site, which became effective on July 1, 2020. Mechanical
removal of water is anticipated to commence in 2021 to support basin closure activities.