3612_Allen_ModifiedClosurePlan_Rev2_Coverletter_FID1897205_20230731

DUKE
ENERGY®
July 31, 2023
VIA ELECTRONIC MAIL
Ms. Sushma Masemore
Assistant Secretary for the Environment
North Carolina Department of Environmental Quality
1601 Mail Service Center
Raleigh, NC 27699-1601
RE: Allen Steam Station Ash Basin Closure Plan (Amended, Revision 2)
Jessica L. Bednarcik
Senior Vice President
EHS and CCP
526 South Church Street, Mail Code: ECI-05A
Charlotte, NC 28202
Phone: [phone]
Email: iessica.bednarcik().duke-energV.com
On August 5, 2020, Duke Energy submitted an amended (Revision 1) Ash Basin Closure Plan detailing the full excavation of
the Active Ash Basin (AAB) and Retired Ash Basin (RAB) (collectively, Basins), including the excavation of the landfill within
the RAB in accordance with the requirements of North Carolina General Statutes § 130A-309.214(a)(4) and Paragraphs 22
and 23 of the Consent Order signed by Duke Energy, the North Carolina Department of Environmental Quality (NCDEQ), and
certain community groups, which was entered in North Carolina superior court on February 5, 2020.
After further discussions and review, Duke Energy has revised the Ash Basin Closure Plan (Amended, Revision 2) to remove
all CCR (except for a small amount of coal ash that is necessary for transmission tower stability) to (4) four new lined
landfills, rather than the (3) three landfills reflected in the amended Closure Plan (Revision 1) submitted on August 5, 2020.
Excavation and placement of the ash in the originally proposed three (3) landfills was found to be difficult to sequence and
operate. In addition, the area where the fourth landfill is proposed to be sited was not previously considered because plant
retirement at the time was estimated to be around 2029. However, plant retirement is now scheduled for 2024. By
evaluating likely excavation sequencing, we found that constructing the North Starter Landfill (NSLF), South Starter Landfill
(SSLF), Canal Road Landfill (CLF), and then the Ash Basin Landfill (ABLF) would facilitate ash excavation and ease staging
landfill cell construction. The landfills are within plant property, with the NSLF, SSLF, and ABLF located partially within the
prior footprint of the Basins and the CLF partially located within the lined retention basin.
Closure activities for the Basins have already begun with the completion of decanting, continued dewatering, limited CCR
excavation to support NSLF and SSLF, and NSLF and SSLF construction. Additional actions are underway and future actions
include development and construction of the CLF and ABLF in conjunction with excavation of the CCR, final grading of the
site and landfills, and development of stormwater features and vegetative covers.
The enclosed Ash Basin Closure Plan (Amended, Revision 2) also includes a description of the Post -Closure Plan, which
provides a description of the inspection, monitoring, and maintenance activities required to be performed throughout the
30-year post -closure care period for the closed Basins at the Allen Steam Station.
Respectfully submitted,
Jessica L. Bednarcik
Senior Vice President
w/attachment: CAMA Allen Ash Basin Closure Plan (Amended, Revision 2)
NCDEQ cc: [e-mail], Ed Mussler, Eric Smith, Toby Vinson, Claire Osborn
Duke Energy cc: Tim Hill, Zach Hall, Ed Sullivan, Michael Kafka, Randy Hart, Diana Kooser, [e-mail],
Kyle Baucom, Charlie Hiner, David Beck, Courtney Murphy
AECOM cc: Jay Mokotoff, P.E.