Under a settlement agreement with community and environmental groups and Duke Energy that ends the appeal litigation, Duke Energy will move forward with excavation plans at the Mayo Steam Station and dispose of ash in a lined onsite landfill.
Duke submitted a closure plan by the December 31, 2019 deadline, as required by the Coal Ash Management Act (CAMA) of 2016 and in accordance with the agreement. On April 29, 2020, DEQ issued its approval for the closure plan. Access historical Public Meetings.
Division of Air Quality
Division of Waste Management
Permit 7307-INDUS-2021, Mayo Ash Basin Landfill
- Ash Basin Landfill Permit To Construct Cover Letter, Mayo Plant
- Ash Basin Landfill Permit Permit to Construct, Mayo Plant
- Ash Basin Landfill Hearing Officer's Report, Mayo Plant
- Public Hearing Presentation, Mayo Plant
- Ash Basin Landfill Factsheet, Mayo Plant
- Ash Basin Landfill Documentation, Mayo Plant
- Public Notice, Mayo Plant - Public Hearing on August 10, 2021
- DRAFT Environmental Justice Report, Mayo Plant
- Site Study, Mayo Plant
- Geological and Hydrogeological Report, Mayo Plant
- Notification of Site Suitability, Mayo Plant
- Engineering and Facility Plant, Mayo Plant
- Technical Specifications, Construction Quality Assurance Plan, Closure and Post-Closure Plan, Mayo Plant
- Environmental Controls Monitoring Plan, Mayo Plant
- Operations Plan, Mayo Plant
The Coal Ash Management Act (CAMA) provides three principal closure pathways:
- Option A: closure in a manner allowed for a high-risk site, such as excavation and disposal in a lined landfill
- Option B: closure with a cap-in-place system similar to the requirements for a municipal solid waste landfill
- for this option, there is a further requirement that upon full implementation of the closure plan, the groundwater must be in compliance with the 2L standard at the compliance boundary of the impoundment.
- Option C: closure in accordance with the federal CCR rule adopted by the EPA.
After conducting a rigorous scientific review of Duke Energy’s proposals for Mayo, and conducting public listening sessions in impacted communities, DEQ has determined Option A is the only closure option that meets the requirements of Coal Ash Management Act to best protect public health and the environment. Coal ash must be excavated and moved to a lined landfill.
DEQ's Coal Ash Impoundment Closure Determination (April 1, 2019)
Comprehensive Site Assessment -- Report, Figures, Tables, and Appendices