1812_DukeMarshall ILF _Leachate ReleaseEvent_20250903_FID2104151_20250913

('DUKE
ENERGY Solid Waste Event Reporting
Event Title: Industrial Landfill No. 1, Cell 5 Force Main Leachate Release
Event
Report Date: September 13, 2025
Submitted to: NCDEQ Division of Waste Management (DWM)
Regulatory agency contact: Deana Yitbarek; 919-707-8299, and Sarah Moutos; 919-707-8287
Duke Energy contact: Anne Davin; 919-616-2333
Duke Energy Facility: Marshall Steam Station
8320 North Carolina Highway 150 East
Terrell, NC 28682
Catawba County
Industrial Landfill No. 1 (1812-INDUS-2008)
1. Event Description
• Date:
Event occurred and discovered on September 3, 2025.
Material released:
()Les/No). Description if yes: Approximately 200 gallons of leachate and
impacted groundwater was released from the Industrial Landfill
No. 1 Cell 5 Force main and recently tied -in Cell 5 underdrain.
• Summary:
• At approximately 12:00 pm on September 3, 2025, while installing a stormwater
trench to reroute stormwater away from the construction area of the future
Industrial Landfill No. 1 (ILF) Phase 4 (Cell 8) area, an excavator bucket came in
contact with the leachate force main for Cell 5 and created a release of leachate.
• The release was located to the west of the ILF Phase 2 (Cell 5) area and to the
north of the MAR-145 stormwater pond, outside of the waste boundary for the
ILF and the ash basin footprint.
• The release was immediately contained within the small, excavated area using a
berm already in place to support the stormwater trench. This is not considered an
environmental release.
• The force main and underdrain was immediately turned off to prevent further
release of leachate.
• The volume of released leachate and groundwater from the Cell 5 underdrain
(tied into the leachate force main the week prior) was approximately 200 gallons.
• The leachate and groundwater was pumped into a tote and then disposed of in
the ILF.
• Soil material that came in contact with the released leachate and groundwater
was excavated and disposed of in the ILF.
• As of 2:30 pm on September 4, 2025, the leachate force main was repaired and
returned to service.
• Field actions completed to date:
• The released liquid was immediately contained using a soil berm and pumped
into a tote.
• The force main was immediately taken offline.
Marshall Industrial Landfill No. 1 (1812-INDUS-2008) - Solid Waste Reporting Page 1 of 5

The tote containing the release liquid was disposed of in the ILF.
The wet soil that came into contact with the released liquid was excavated and
disposed of in the ILF.
Repairs were completed by September 4, 2025, at approximately 2:30 pm.
2. Regulatory Contact
• Date and time of regulatory contact:
September 4, 2025, at approximately 10:32 am
Regulatory agency:
NCDEQ Division of Waste Management (DWM)
Contact name/number:
Primary — Sarah Moutos. 919-707-8287
Summary:
Phone conversation describing the event, location of the release, and
containment methodology. Actions taken to contain, pump, excavate, and
dispose of released liquid and wet soil in Industrial Landfill No. 1 (ILF). Described
actions being taken to repair the leachate force main and return the force main to
service. At this time a site visit was not requested.
3. Regulatory Site Visit
Was a regulatory visit conducted (Yes/No).
4. Regulatory Recommendations:
• Provide and update the Solid Waste Event Report summarizing the event and actions
taken to remedy the damage to the force main.
• Continue to update NCDEQ DWM with any changes to the conditions, including
providing notification of the when the force main was returned to service.
5. Duke Energy Follow -Up Actions:
• Prepare and submit the Event Report to NCDEQ.
• Provide updates to NCDEQ if conditions of the area change; submit an updated Event
Report to NCDEQ, as necessary.
6. Repair Plan
• Contain released liquid in area of release.
• Pump released liquid into a tote and excavate wet soil for disposal into the ILF.
• Conduct repairs to the force main to repair damaged section (Completed 9/4/25).
• Test force main to confirm repairs were successful (Completed 9/4/25).
• Return force main to service (Completed 9/4/25).
7. Repair Completed
• Repairs to the force main were completed by September 4, 2025, and included:
o the installation of an HDPE electrofusion coupling,
o force main testing to confirm repairs were successful, and
o The force main was returned to service.
8. Photos: See pages below.
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Photo 1: Photo of leachate release. September 3, 2025, at approximately 2:00pm.
Photo 2: Photo of damage to leachate line and leachate release. September 3, 2025, at
approximately 2:00 pm.
Marshall Industrial Landfill No. 1 (1812-INDUS-2008) - Solid Waste Reporting Page 3 of 5

Photo 3: Photo of repair to the leachate force main for Cell 5. September 4, 2025, at
approximately 2:30 pm.
Marshall Industrial Landfill No. 1 (1812-INDUS-2008) - Solid Waste Reporting Page 4 of 5

cc: Deana Yitbarek — NCDEQ DWM
Sarah Moutos - NCDEQ DWM
Sherri Stanley - NCDEQ DWM
Dan Zakary - Duke Energy
Scott Saunders - Duke Energy
Jake Muessen — Duke Energy
Chris Varner - Duke Energy
Ed Sullivan - Duke Energy
Ashley Healy — Duke Energy
Tyler Hardin - Duke Energy
Kim Witt - Duke Energy
Marshall Industrial Landfill No. 1 (1812-INDUS-2008) - Solid Waste Reporting Page 5 of 5