Department of Ecology News Release - April 29, 2024

State of Washington, federal agencies agree on future of tank waste cleanup at Hanford Site

Proposed amendments to cleanup agreements to go out for 60-day public comment period May 30.

An aerial view of the Hanford Site's 200 Area, where the Waste Treatment Plant and underground storage tanks reside. 


Today, the U.S. Department of Energy (USDOE), Washington State Department of Ecology (Ecology), and U.S. Environmental Protection Agency (EPA) announced a landmark agreement that proposes a realistic and achievable course for cleaning up millions of gallons of radioactive and chemical waste from large, underground tanks at the Hanford Site.

Following voluntary, mediated negotiations that began in 2020, also known as Holistic Negotiations, the agencies have signed a settlement agreement and are proposing new and revised cleanup deadlines in the Tri-Party Agreement and Washington v. Granholm consent decree. The proposed changes uphold a shared commitment to the safe and effective cleanup of tank waste.

Highlights of the proposed modifications include the following:

  • Maintaining existing timeframes for starting treatment of both low-activity and high-level waste by immobilizing it in glass via vitrification
  • Using a direct-feed approach for immobilizing high-level waste in glass, similar to the Direct-Feed Low-Activity Waste Program
  • Building a vault storage system and second effluent management facility to support treating high-level waste
  • Retrieving waste from 22 tanks in Hanford’s 200 West Area by 2040, including grouting the low-activity portion of the waste for offsite disposal.
  • Designing and constructing 1-million gallons of additional capacity for multi-purpose storage of tank waste
  • Evaluating and developing new technologies for retrieving waste from tanks

Under the settlement agreement, USDOE has also committed to refrain from applying its interpretation of what constitutes “high-level waste” when disposing of treated waste or closing tank systems at Hanford.

Proposed changes to the Tri-Party Agreement and consent decree will go out for a 60-day public comment period May 30. During the comment period, the three agencies will hold regional public meetings in Washington and Oregon. Detailed information on these meetings will be available when the comment period begins.

Changes to milestones and deadlines are not final until the public comment period is complete, a response to comments is issued, the federal district court accepts the proposed amendments to the consent decree, and the agencies implement the proposed revisions.

Statements from TPA agency leadership:

“We have alignment on a plan that lays out a realistic and achievable path forward for Hanford’s tank waste mission,” said Brian Vance, Hanford’s DOE manager of the River Protection and Richland Operations offices. “Our One Hanford team is ready to get down to the business of more fully conducting the tank waste mission resulting in benefits for the environment, the people of Washington state and the nation.”

“We’ve negotiated a durable framework that aligns our agencies and accelerates work while maintaining a robust and safe cleanup. The communities we all serve deserve no less,” said Ecology Director Laura Watson. “This agreement will get more tank waste retrieved, treated, and disposed of on schedule and gives us a roadmap for Hanford cleanup through 2040 and beyond.”

“The disposal of tank waste is a critical component of the complex, site-wide cleanup efforts at Hanford,” said EPA Region 10 Administrator Casey Sixkiller. “This agreement builds on decades of work and collaboration between the Department of Energy, State of Washington, and the EPA, and will guide the tank waste mission as it enters a new phase of operation. We encourage all impacted Tribes, community members, and other stakeholders to participate in the public review process.”


Producing plutonium at the Hanford Site left a legacy of about 56 million gallons of radioactive and chemically hazardous waste stored in 177 underground tanks. USDOE is responsible for the Hanford Site and its cleanup. Ecology and EPA are regulatory agencies overseeing USDOE’s cleanup under the Tri-Party Agreement, a judicial consent decree, and various permits.

For background information on Hanford, visit USDOE’s Hanford website and Ecology’s website.

Contact information

Ryan Miller
Washington Department of Ecology
Twitter: EcyHanford
Geoffrey Tyree
U.S. Department of Energy
Beth Clemons
U.S. Environmental Protection Agency