SRNL Nuclear Clean-up Services ‘Put Science to Work’


For the past 60 years, Savannah River National Laboratory (SRNL) has successfully applied science and technology to provide practical solutions to some of the most challenging problems our country has confronted. In 2004, the laboratory was designated a national laboratory with a focus on safe containment and disposition of nuclear waste and materials, environmental cleanup, and decontamination and decommissioning of nuclear facilities. Through these diverse activities, SRNL has successfully “put science to work.”

Through its long history of work in the field, SRNL has generated a robust portfolio of cleanup and remediation capabilities. A new Forum on Energy infographic demonstrates and visualizes SRNL’s range of services. The services are explained in greater depth below the graphic. Feel free to save and use this image as part of your online resources, with a link back to this post.

See also:
The Cleanup Challenge at Fukushima Daiichi and U.S.-Japan Collaboration
Q&A with Dr. Jeff Griffin, Associate Laboratory Director for Environmental Stewardship at SRNL

 SRNL Puts Science to Work

 

SRNL Capabilities

SRNL’s 60-year history supporting remediation at the Savannah River Site (SRS) and roles that engage laboratory expertise from concept to completion have generated a remarkable portfolio of cleanup and remediation capabilities and talent.

Deactivation, Decontamination and Decommissioning Technologies and Practices

SRNL and SRS successes in deactivating, decontaminating and decommissioning nuclear facilities and structures are numerous. Efforts have ranged from decontamination and removal of hot cells to in-situ decommissioning of nuclear reactors. Procedures are in place at SRS to direct all aspects of deactivation and decommissioning. The deactivation and decommissioning practices are supported by Performance Assessments to ensure long-term performance of the decommissioned structure. More importantly, experienced personnel reside at SRNL and SRS to support planning, deployment and monitoring of deactivation, decontamination and decommissioning activities.

Cementitious Waste Forms and In-situ Decommissioning

SRNL is the Department of Energy (DOE) complex leader in the development of cementitious waste forms and grout formulations for entombment of radiological facilities. Cementitious formulations are currently used to immobilize low activity wastes resulting from high activity waste separations processes at SRS. Specialized grouts have been formulated for entombment of high activity waste tanks and deactivated nuclear reactor facilities. The grouts used for entombment were specifically formulated to be more flowable and with a lower pH to minimize chemical reaction with structural components. The performance of the grout formulations have been studied extensively by SRNL and the use of cement-based materials for long-term disposition of facilities are supported by detailed Performance Assessments. The use of cement-based materials is a cost effective option for treatment of wastes and long-term disposition of deactivated facilities.

Radioactive Liquid Waste Treatment Technologies

SRNL has been a leader in the development and deployment of high activity radioactive waste treatment technologies. The processes used in the treatment and vitrification of high activity waste at SRS were developed and demonstrated at SRNL prior to deployment, and SRNL has actively supported technology development efforts associated with the Hanford Waste Treatment and Immobilization Plant (WTP). SRNL has provided continual support to high activity waste treatment activities at SRS and continues to develop innovative technologies to improve operations. The Rotary Microfilter (RMF) is a technology that has shown significant promise to filter solids from radioactive waste solutions. The RMF is compact in size yet provides exceptional removal efficiencies and throughput rates. Cesium removal technology advancements include development of an improved solvent for use in a solvent extraction process as well as ion-exchange resins and media. A modified Monosodium Titanate (mMST) material was recently developed at SRNL to improve the removal efficiency of strontium and actinides from SRS wastes. SRNL has also demonstrated technologies to precipitate salt species from high activity waste to facilitate radionuclide removal. SRNL has also developed on-line and at-line monitors for waste pretreatment processes.

SRNL has developed glass formulations and vitrification technologies to immobilize radioactive wastes for permanent disposal. This has included development of a Transportable Vitrification System (TVS) that included feed preparation, melting and off-gas capabilities for treatment of low activity wastes, and provides consulting, technology assessment, technology development and systems planning to all areas of radioactive water and sludge waste treatment.

Reactor and Pipe Repair Technologies

SRNL engineers have developed materials and processes for in-service repair of radioactive tanks, piping and reactor vessels. These efforts have included identifying and evaluating the suitability of off-the-shelf sealant and gasket materials to development of metal weld repair processes. Teaming with remote system and robotic experts at SRNL has resulted in successful deployment of repair solutions in operating radioactive facilities at SRS. SRNL could provide consultation in identifying and evaluating repair options.

Solid Waste Disposition Technologies

Handling, storage and disposition of solid radioactive wastes (including radioactive packaging and transportation) have been conducted at SRS since the inception of the site. Procedures and practices are in place to meet all regulatory requirements associated with solid waste disposition. Advanced concepts in storage vault and shallow burial facility designs have resulted in increased safety and cost effectiveness in the storage and disposition of solid wastes. These advances include unique trench designs and cap/cover technologies to preclude radionuclide release to the environment.

Caps/Covers and Inclusion of Special Amendments

Cover and cap systems have been used on almost 1,500,000 m2 of burial and remediation areas at SRS. The majority of covers have been engineered (geosynthetic, compacted clay, asphalt/ concrete) but soil covers (compacted fill, native soil) have been used in some instances. Recently, amendments have been developed and incorporated into the cap and cover systems to improve performance.

Barriers and Treatment of Groundwater

SRNL has developed technologies that have been successful in the clean-up of groundwater and soil contaminated with radioactive and hazardous species. Extensive site characterization is the first step in treatment. Based on the characterization data, a science-based approach is used to identify target zones with the dominant contaminant characteristics and to aggressively clean up the targeted zones using appropriate technology solutions. Pump and treat, “funnel and gate” barrier and amendment systems have been developed and deployed at SRS. SRNL can provide consultation and support the development of groundwater clean-up strategies.

Radiation Monitoring and Mapping Technologies

Scientists at SRNL developed and tested devices with accessories, to locate, identify, and generate maps of radioactive contamination in outdoor and enclosed areas. These devices use detectors that are highly sensitive which translates into shorter counting times while performing radiological measurements and surveys. This allows the devices to quickly identify the type and location of radioactive sources. The devices can be deployed on remotely operated platforms to allow for radiological measurements in confined and high dose locations. The RadmapperTM and GrayQbTM technologies could be of significant value in supporting radiological assessments and radiation exposure reduction.

Robotic and Remote Technologies

SRNL is a leader in the development and deployment of remote technologies for radioactive and hazardous applications. At SRNL, technical staff from a variety of engineering disciplines work together to integrate commercial off-the-shelf technology with in-house designs to develop cost-effective, field-deployable solutions. Remote systems have been deployed to perform inspections, radiological surveys, repairs and modifications in outdoor locations, buildings, tanks and piping systems. One of the most innovative systems developed was a pipe crawler that operated pneumatically. The use of pneumatics increased the reliability and cost effectiveness of the crawler in the remote environment. Consultation and/or system development could be supported by SRNL.

Wet Storage Overpacks for Fuel and Debris and Fuel Pool Water Treatment

Oversized storage containers have been utilized at SRS to package and store damaged reactor fuel and debris in spent fuel pools. This has provided a convenient way to consolidate damaged fuel and debris to facilitate water clean-up and movement/transportation of damaged fuel. An advanced “J-tube” design was developed by SRNL to improve the safety of the storage containers by controlling gas release from the containers. Ion exchange resin has also been incorporated into the storage containers to capture cesium from leaking fuel.

In-pool water clean-up systems have also been developed by SRNL. These systems include pumps, filters and ion-exchange resin column systems to clean-up the water in the spent fuel pools. The water clean-up systems are portable, skid mounted units to allow for easy insertion and removal from the fuel pools. SRNL has also developed water treatment systems to eliminate biological complications resulting from fungal and bacterial growth. Additionally, SRNL has extensive experience in the area of corrosion evaluation in fuel pools and radioactive waste tanks. This experience includes developing water chemistry control programs to mitigate corrosion.