NC0004961_Special Order By Consent_20181025

_ r
(, DUKE
ENERGY® James Wells
Vice President
Environmental,Health&Safety-
Programs and Environmental Sciences
526 South Church Street
Mail Code EC13K
Charlotte,NC 28202
[phone]
October 25, 2018
Via Overnight Mail
Corey Basinger
Mooresville Regional Supervisor
North Carolina Department of Environmental Quality
Division of Water Resources �ECElVEDIDEMRIDWR
Regional Water Quality Operations Section
601 East Center Avenue, Suite 301 OC 2M$
Mooresville, NC 28115
Bob Sledge Water ReS$ectlon
perm►tttng
North Carolina Department of Environmental Quality
Water Quality Permitting Program
Division of Water Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
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:
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
October 25, 2018 2018
Page 2
Please direct any questions concerning the Riverbend Steam Station NPDES Permit
NC0004961 SOC No. S16-005 to Brad Loveland at [phone].
Sincerel
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

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 S16-005 (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 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 originally contained
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
July 1, 2018 to September 30, 2018, Riverbend excavated 330,545 tons of ash from the site and
transported it by rail to the Brickhaven Structural Fill site near Moncure, North Carolina. As of
September 30, 2018, approximately 4.81 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 21, 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 within 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.
1

Ash Transported in Thousands of Tons I April 2018 to September 2018
160 Riverbend Ash Transportation
140
120 --
100 —
F
80 ----
19111
■PPlan
■Frev aou s Plan
40 -- . ■Actual
40 --
2'9 —
0
Apr 18 Map 18 Jun 18 Jul 18 Aug 18 Sep 18
_,--_ - - f_,-: -bon date of8(20/18.
- • _• - - .. ,letion of 11121118.
Ash Transported in Millions of Tons I May 2015 to November 2018
Riverbend Ash Transportation
5.0
4.0
8
3.0 . — - ---
-
E
2.0
1.0 -
0.0
ti\tiy ,\ti`' 1\ti' 1\�0 \tib \Nb y\tib „\i" \tip \� 1\�` 44, 4:,° \•• \,o ,\'+9 ,y\'+0 \,a
o 1. o$\~ ,� eIN c1,\ ,\ ,+iL otic o5\ti �Cti ,,\ti c10 c)41' om\ti s ay\� oy\ti c0.1.
fa Regulatory Date: —Forecast --Current Plan —Actual
8/1/19
•Pr<_wwus Plan as of 1/1118 assumed 4.77M tons with a forecast .npletion date of 8/20(18.
•Current Plan as of 8/1/18 assumes 4.86M tons wtth a forecast completion of 11/21118.
2

•
Status of Permits and Permit Applications
RECEIVED DATE (R)
MEDIA PERMIT TARGET DATE (T) COMMENTS
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 2016R
( ) Permit became effective
Permit— Major (Modified by SOC
Water Modification In Q4 2016) December 1, 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 and
Decommissioning June 16, 2016 (R) received approval June 16,
Request Approval 2016. Decommissioning
completed 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 June 12, 2018 (R) Dam decommissioning plan
Decommissioning 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