Salt Waste Processing Facility

Salt Waste Processing Facility
Name	Salt Waste Processing Facility
Location	Savannah River Site, South Carolina
Status	Operational
Owner	United States Department of Energy
Operator	Savannah River Nuclear Solutions
Industry	Radioactive waste treatment
Products	Decontaminated salt solution, Strontium/Actinide slurry
Built	2002–2021
Opened	2022

Salt Waste Processing Facility. A major radioactive waste treatment plant located at the Savannah River Site in South Carolina, designed to process the site's large inventory of radioactive salt waste. The facility is a cornerstone of the United States Department of Energy's environmental cleanup mission, employing advanced separation technologies to treat waste stored in massive underground tanks. Its operation is critical to closing waste tanks and preparing waste for permanent immobilization.

Overview

The facility was constructed to address one of the most significant environmental legacies of the Cold War at the Savannah River Site, which produced materials for the nation's nuclear weapons program. The project is managed by the DOE Office of Environmental Management and executed by the site's management and operations contractor, Savannah River Nuclear Solutions. Its primary mission is to accelerate the treatment of approximately 36 million gallons of salt waste stored in aging tanks like those in the F-Area and H-Area tank farms, a task previously handled by the smaller Salt Waste Processing Facility and the Actinide Removal Process/Modular Caustic Side Solvent Extraction Unit. Successful operation directly supports compliance with agreements like the Federal Facility Agreement with the South Carolina Department of Health and Environmental Control and the United States Environmental Protection Agency.

Design and Technology

The design centers on the Caustic Side Solvent Extraction process, a robust liquid-liquid extraction method developed from research at the Argonne National Laboratory. This technology selectively removes key radionuclides, including Cesium-137, Strontium-90, and Actinides, from the salt waste stream. The facility integrates two primary processing lines: the Alpha Recovery Process for concentrating actinides and strontium into a small-volume slurry, and the main Salt Waste Processing Facility line for cesium removal. The design emphasizes modular construction and includes extensive support structures such as the Salt Solution Feed Tank, Process Water System, and the Waste Handling Building, with construction managed by a consortium including Parsons Corporation and Bechtel.

Operational History

Major construction began in 2002 but faced significant delays and cost overruns, leading to a major redesign and resequencing of the project in the 2010s. The facility achieved a critical milestone with the completion of Cold Chemical Testing in 2018, using non-radioactive simulants to verify systems. Following regulatory approvals, including from the DOE Savannah River Operations Office, the facility initiated radioactive operations with a "hot test" in 2021. It was formally commissioned and began full operations in 2022, treating its first batch of waste from the H-Area Tank Farm. Performance has since been monitored against key parameters outlined in the Waste Determination and Safety Basis documents approved by the DOE Office of Safety, Infrastructure and Operations.

Waste Processing and Immobilization

The process begins by transferring salt waste from storage tanks to the facility's feed tank. The Caustic Side Solvent Extraction process separates cesium, which is then directed to the Defense Waste Processing Facility for vitrification into borosilicate glass within stainless steel canisters. The decontaminated salt solution, termed "low-activity waste," is sent to the Saltstone Production Facility where it is mixed with a cementitious grout to form a monolithic waste form called Saltstone, which is disposed of in onsite vaults. The separated actinide and strontium slurry is transferred to the Tank Closure Cesium Removal system or prepared for future treatment and disposal.

Safety and Environmental Considerations

Safety is governed by a rigorous Documented Safety Analysis and technical safety requirements compliant with DOE Order 420.1C. The facility incorporates multiple engineered safety features, including confinement systems, seismic design to standards from the American Society of Civil Engineers, and extensive instrumentation for monitoring. Environmental protection is achieved by drastically reducing the volume of high-level waste, thereby lowering the long-term risk of tank leaks into the local aquifer. Operations are conducted under the oversight of the Defense Nuclear Facilities Safety Board and in accordance with the Resource Conservation and Recovery Act and the Comprehensive Environmental Response, Compensation, and Liability Act.

Future Developments and Challenges

Future work focuses on ramping up to its design capacity of 6 million gallons per year to meet the accelerated tank closure schedule for the Savannah River Site. Key challenges include managing the integration of waste streams from other treatment facilities like the Tank Side Cesium Removal project and ensuring the long-term reliability of the solvent extraction equipment. Research into next-generation waste forms, potentially involving partnerships with Idaho National Laboratory or Pacific Northwest National Laboratory, may influence future processing. The facility's sustained performance is essential for the broader DOE Environmental Management goal of remediating the entire Savannah River Site tank farm complex.

Category:Nuclear technology in the United States Category:Radioactive waste management in the United States Category:Savannah River Site Category:Buildings and structures in South Carolina