The Office of Environmental Management (EM) tank waste program consists of safely storing of 90 million gallons of radioactive liquid waste at the Savannah River Site (SRS), Idaho National laboratory (INL) and the Office of River Protection (ORP) at Hanford, Wash. Of the approximately 90 million gallons, 36 million gallons (250 x 10⁶ Ci ) is stored at SRS, approximately 56 million gallons (109 x 10⁶ Ci) is located at ORP while 900,000 gallons of liquid sodium bearing waste (300,000 Ci) is at INL. In addition, EM operates major nuclear facilities to process and dispose of the waste as well as emptying, cleaning and closing the waste tanks. The SRS and ORP waste streams treatment involves separating the highly radioactive fractions and low activity factions. The high activity portion undergoes vitrification while the low activity portion is then either vitrified or grouted. 

As liquid waste is processed, the tanks are operationally closed through a process that involves: bulk waste removal, heel removal, cooling coil flushing/annulus cleaning, isolation and residual sampling and grouting. To date 15 large High Level Waste Tanks, eight at SRS and seven at INL, have been operationally closed and grouted.  In addition, four small INL waste tanks have also been operationally closed and grouted.

The EM tank waste program’s goal is to continue cleanup progress in a cost-effective manner that is risk informed, engages stakeholders, applies innovative solutions and provides value to the American taxpayer.

Current EM nuclear processing facilities include:

Savannah River Site

• Defense Waste Processing Facility – vitrifies the highly radioactive portion of the liquid waste;
• Glass Waste Storage Building  – stores the glass canisters from the DWPF;
• Salt Waste Processing Facility (SWPF) –uses the same technology as the ARP/MCU but has a much higher throughput;
• Saltstone Disposal Facility (SDF) – manages the low level effluent stream from the ARP/MCU or the SWPF for grouting and disposal on site at a Saltstone Disposal Unit.

Office of River Protection

• Waste Treatment and Immobilization Plant (WTP) (under construction) – designed to vitrify both the high and low activity portions of the liquid tank waste with the current plan to initiate operations with low activity waste vitrification, Direct Feed Low Activity Waste.

Idaho National Laboratory (INL)

• Integrated Waste Treatment Unit – designed to treat sodium bearing high level radioactive waste using Fluidized Bed Steam Reforming that decomposes waste using super-heated steam to produce a sodium-alumino-silicate mineralized waste form that can be packaged for disposal.