NC0004961_SOC16005Report_20180726

4 DUKE
ENERGY.
July 26, 2018
Via Overnight Mail
Corey Basinger
Mooresville Regional Supervisor
North Carolina Department of Environmental Quality
Division of Water Resources
Regional Water Quality Operations Section
601 East Center Avenue, Suite 301
Mooresville, NC 28115
Bob Sledge
North Carolina Department of Environmental Quality
Water Quality Permitting Program
Division of Water Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
James Wells
Vice President
Environmental, Health & Safety -
Programs and Environmental Sciences
526 South Church Street
Mail Code EC13K
Charlotte, NC 28202
Subject: Report Under Special Order by Consent - SOC No. S16-005
Duke Energy Carolinas, LLC - Riverbend Steam Station
NPDES Permit NC0004961
Dear Mr. Basinger and Mr. Sledge:
REC�I� W-ISENR/DWR
JUL 27 2018
WQROS
MOORESVILLE REGIONAL OFFICE
On behalf of Duke Energy Carolinas, LLC (DEC), I am submitting to you the Riverbend Steam
Station Progress Report summarizing the work and activities undertaken with respect to closure
of coal ash surface impoundments as required by the Riverbend Steam Station NPDES Permit
NC0004961 Special Order by Consent (SOC), SOC No. S16-005 Section 2.d.
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. Corey Basinger and Mr. Bob Sledge
July 26, 2018
Page 2
Please direct any questions concerning the Riverbend Steam Station NPDES Permit
NC0004961 SOC No. S16-005 to Brad Loveland at [phone].
Sincerely,
James Wells
Vice P sident, Environment, Health & Safety -
Programs and Environmental Sciences
Duke Energy
CC: Richard Baker, Duke Energy
Brad Loveland, Duke Energy
Rick Massey, Duke Energy
George Hamrick, Duke Energy
Paul Draovitch, Duke Energy
Matt Hanchey, Duke Energy

NPDES PERMIT NC0004961
SPECIAL ORDER BY CONSENT EMC SOC WO 516-005
QUARTERLY EXCAVATION PROGRESS REPORT
RIVERBEND STEAM STATION
JULY 26, 2018

I. Background and Summary
On November 10, 2016, Duke Energy Carolinas, LLC (DEC) and the North Carolina
Environmental Management Commission entered into Special Order by Consent — EMC SOC
WQ S 16-005 (SOC) applicable to the Riverbend Steam Station (Riverbend). This report is
submitted in accordance with paragraph 2.d of the SOC. In compliance with Section 2.d., this
report summarizes the work and activities undertaken with respect to closure of coal ash surface
impoundments at Riverbend, including a status update for necessary permits. The quarterly
reports are due no later than the last day of January, April, July, and October for the duration of
the SOC.
A. Riverbend Steam Station Closure Summary
Riverbend is located off of Horseshoe Bend Beach Road near the town of Mt. Holly in
Gaston County, North Carolina, on the south bank of the Catawba River. The site contains two
ash basins, as well as the Dry Ash Stack and the Cinder Pit.
The Riverbend site has continued to make progress with excavation efforts. Excavation
of the Primary and Secondary Ash Basins, Ash Stack and Cinder Pit is ongoing. During the
period April 1, 2018 to June 30, 2018, Riverbend excavated 285,301 tons of ash from the site
and transported it by rail to the Brickhaven Structural Fill site near Moncure, North Carolina. As
of June 30, 2018, approximately 4.47 million tons of ash has been excavated from the Riverbend
site.
North Carolina state law requires that ash from the basins at the Riverbend site be
excavated and relocated to a lined facility with the ash basins closed by August 1, 2019. The
current plan is for Riverbend to complete excavation by November 20, 2018 and perform ash
removal verification procedures in advance of the August 1, 2019 compliance date. At present,
Riverbend is not considered at risk for excavation in the required timeframe.
Since completing bulk dewatering in February 2017, the basins have been maintained in a
dewatered state with interstitial and contact stormwater being treated through the on-site water
treatment facility. Post closure activities, including decommissioning of the Primary and
Secondary Dams, will begin following the completion of ash excavation activities.

Ash Transported Off Site in Thousands of Tons I January 2018 to June 2018
Ash Transported Off Site in Millions of Tons I May 2015 to November 2018
Riverbend Ash Transportation
8;1/19
6.0
5.0
40
3.0
Y
1.0
00
1S
)S
)S .•b 1b 41"0 )9
0
)A )9 10
p0\ )1C' 0.1\ �r 6q\ 1)\ O.y\ �r Og\ ).•\'l
O.1\ 6S\1. .r
Y♦ReQUWiary Dace: —F..A —Current Plan—Pre*us Plan —Actml
811(19
•fravi Plan as of 111/18 assumed 4]]M tons wah a forecast completion date of 8/20118.
• torrent Men as M6/I/38 assumes 486M tons •With a forecast completan of 11)21118.

Status of Permits and Permit Aoulications
PERMIT
DATE (R)
RECEIVEDMEDIA
TARGET1
NPDES Industrial
NCDEQ issued the ISW
Stormwater (ISW)
May 15, 2015 (R)
permit on May 15, 2015.
Permit
SPPP implementation date
was November 15, 2015.
NPDES Wastewater
First Quarter 2016 (R)
Permit became effective
Water
Permit — Major
(Modified by SOC in
December 1, 2016
Modification
Fourth Quarter 2016)
Jurisdictional Wetland
There are no identified
and Stream Impacts /
N/A
jurisdictional
404 Permitting
wetland/stream impacts
and 401 WQC
Intermediate Dam
Submitted May 31, 2016.
Decommissioning
June 16, 2016 (R)
Decommissioning completed
Request Approval
March 13, 2017.
Submitted on May 8, 2017.
Primary Dam
Modification was to
Modification Request
August 3, 2017 (R)
remove the top 10 feet of
Dam Safety
Approval
soil from the dam that is
partially founded on ash.
Breach of dike requires Dam
Primary and
Safety approval. Secondary
Secondary Dam
-Decommissioning
June 122018 (R)
Dam decommissioning plan
,
approval required to
Request Approval
remove rip -rap apron from
dam during ash removal.
Mine Reclamation
Owner/Operator obtained
Waste
Individual Structural
October 15, 2015 (R)
an Individual Structural Fill
Fill Permit
(Permit to Operate)
Permit as set forth in Part II,
§ 130A-309.219 of the
Coal Ash Act.
Original permit received
Duke Energy
Water Conveyance
August 2, 2016 (R)
April 7, 2016. Amended
Lake Services
Permit
permit for revised quantities
received August 2, 2016.
Site-specific
Other
Nuisance/Noise/
Requirements
Odor/Other
N/A
None identified
Requirements,
including DOT