Waste Treatment Plant (WTP)
Treating Hanford Tank Waste Through Vitrification
The Hanford Waste Treatment Plant, also known as the WTP or Hanford Vit Plant, is the world’s largest radioactive waste treatment facility. Bechtel National Inc. designed, built, and is commissioning the plant for the U.S. Department of Energy.
The WTP is a key part of Hanford’s long-term tank waste cleanup mission. The waste being treated is part of the approximately 56 million gallons of radioactive and chemical waste generated during past plutonium production and stored in underground tanks on the Hanford Site.
Current Progress
Hanford began vitrifying low-activity tank waste at the Low-Activity Waste Facility in October 2025. By May 2026, crews had turned more than 100,000 gallons of Hanford tank waste into glass, marking a major commissioning milestone for the project.
The milestone represents continued progress in moving Hanford’s vitrification mission from startup toward sustained operations. For the Tri-Cities region, it also represents visible progress on one of Hanford’s most complex cleanup challenges: treating tank waste in a stable form for long-term disposal.
How Vitrification Works
Vitrification combines radiological and chemical waste with glass-forming materials. The mixture is heated to about 2,100 degrees Fahrenheit inside large melters, then poured into stainless steel containers.
As the material cools, it forms a stable glass-like solid for long-term disposal. The containers are sent to Hanford’s Integrated Disposal Facility.
Phased Treatment Approach
Hanford is using a phased approach that begins with low-activity waste treatment through the Direct-Feed Low-Activity Waste program. This approach sends pretreated low-activity waste from Hanford’s tank farms directly to the Low-Activity Waste Facility for vitrification.
Future high-level waste treatment will require additional design, construction, commissioning and startup work. The High-Level Waste Facility is expected to treat the smaller but more radioactive fraction of Hanford’s tank waste, subject to current DOE schedule planning.
Supporting Facilities
Several facilities support the tank waste treatment mission, including the Effluent Management Facility, which processes liquid secondary waste generated during vitrification, and the High-Level Waste Facility, which will support future treatment of high-level tank waste.