A pilot-scale radioactive test using in situ vitrification
Pacific Northwest Laboratory is developing in situ vitrification (ISV) as a potential remedial action technique for previously disposed radioactive liquid drain sites. The process melts the contaminated soil to produce a durable glass and crystalline waste form and encapsulates the radionuclides. The development of this alternative technology is being performed for the US Department of Energy. The results of an ISV pilot-scale test conducted in June 1983 are discussed in which soils contaminated with actual radioactive transuranic and mixed fission product elements were vitrified. The test successfully demonstrated the containment of radionuclides during processing, both within the vitrified mass and in the off-gas system. No environmental release of radioactive material was detectable during testing operations. The vitrified soil retained >99% of all radionuclides. Losses to the offgas system varied from less than or equal to 0.03% for particulate materials (plutonium and strontium) to 0.8% for cesium, which is a more volatile element. The off-gas system effectively contained both volatile and entrained radioactive materials. Analysis of the vitrified soil revealed that all radionuclides were distributed throughout the vitrified zone, some more uniformly than others. Analysis of soil samples taken adjacent to the block indicated that no migration of radionuclides outside the vitrification zone occurred. Leaching studies have shown that the ISV process generates a highly durable waste form, comparable to Pyrex and granite. Based on geologic data from the hydration of obsidian, which is chemically similar to the ISV glass, the hydration or weathering rate is predicted to be much less than 1 mm in 10,000 yr.
- Research Organization:
- Pacific Northwest Laboratory, Richland, WA
- OSTI ID:
- 5990550
- Journal Information:
- Nucl. Technol.; (United States), Vol. 71:2
- Country of Publication:
- United States
- Language:
- English
Similar Records
In-situ vitrification: pilot-scale development
Off-gas treatment and characterization for a radioactive in situ vitrification test
Related Subjects
54 ENVIRONMENTAL SCIENCES
ALPHA-BEARING WASTES
IN-SITU PROCESSING
UNDERGROUND DISPOSAL
VITRIFICATION
SOILS
RADIONUCLIDE MIGRATION
WASTE FORMS
LEACHING
RADIOCHEMICAL ANALYSIS
CONTAINMENT
ENCAPSULATION
FISSION PRODUCTS
HYDRATION
OFF-GAS SYSTEMS
RADIOACTIVE WASTE DISPOSAL
RADIOACTIVE WASTE PROCESSING
TESTING
CHEMICAL ANALYSIS
DISSOLUTION
ENVIRONMENTAL TRANSPORT
ISOTOPES
MANAGEMENT
MASS TRANSFER
MATERIALS
PROCESSING
QUANTITATIVE CHEMICAL ANALYSIS
RADIOACTIVE MATERIALS
RADIOACTIVE WASTES
SEPARATION PROCESSES
SOLVATION
WASTE DISPOSAL
WASTE MANAGEMENT
WASTE PROCESSING
WASTES
052001* - Nuclear Fuels- Waste Processing
510301 - Environment
Terrestrial- Radioactive Materials Monitoring & Transport- Soil- (-1987)