Validation of methods for evaluating radon-flux attenuation through earthen covers

Technical Report · Mon Oct 01 00:00:00 EDT 1984

OSTI ID:6455524

Kalkwarf, D R; Freeman, H D; Hartley, J N

Field and laboratory measurements were made to test the validity of methods for calculating radon-flux attenuation through earthen covers as described in A Handbook for the Determination of Radon Attenuation Through Cover Materials, NUREG/CR-3533. Radon flux was measured at several sites on two, different, earthen-cover systems over uranium-mill tailings. Afterwards, the underlying materials were removed; and their properties which govern radon diffusion were measured. The validity of the diffusion equations presented in the handbook was established by the generally good agreement between the measured radon flux and the flux predicted when measured values of soil properties were used in these equations. Also, approximate values presented in the handbook for various soil properties were compared with those measured on samples collected at the test sites and were generally found to agree within a factor of four. When these approximate values were used in the diffusion equations, the predicted fluxes were larger than the measured values by factors of up to 31. This implies that the diffusion equations will overestimate the depth of cover soil required to attenuate radon flux to a prescribed level if these approximate values are used. However, investigation of the theoretical relationship between the radon flux from an earth-covered tailings pile and the thickness of that cover indicated that the latter would only be overestimated by a factor of up to 1.5 at field sites similar to those examined in this study. In addition, measurements of radon flux over the drill holes indicated that these cover defects, penetrating the entire thickness of the cover but accounting for only 0.07% of its surface area, had negligible effect on the average flux from the cover system. 13 references, 1 figure, 12 tables.

• Research Organization: Pacific Northwest Lab., Richland, WA (USA)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 6455524
• Report Number(s): NUREG/CR-3457; PNL-5092; ON: TI85001201
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
54 ENVIRONMENTAL SCIENCES
MILL TAILINGS
COVERINGS
RADON
DIFFUSION
SOILS
RADIONUCLIDE MIGRATION
ATTENUATION
BULK DENSITY
MANUALS
MEASURING METHODS
RADIATION FLUX
RADIUM 226
RADON 222
VALIDATION
ALKALINE EARTH ISOTOPES
ALPHA DECAY RADIOISOTOPES
DAYS LIVING RADIOISOTOPES
DENSITY
DOCUMENT TYPES
ELEMENTS
ENVIRONMENTAL TRANSPORT
EVEN-EVEN NUCLEI
FLUIDS
GASES
HEAVY NUCLEI
ISOTOPES
MASS TRANSFER
NONMETALS
NUCLEI
PHYSICAL PROPERTIES
RADIOISOTOPES
RADIUM ISOTOPES
RADON ISOTOPES
RARE GASES
SOLID WASTES
TAILINGS
TESTING
WASTES
YEARS LIVING RADIOISOTOPES
053000* - Nuclear Fuels- Environmental Aspects
052002 - Nuclear Fuels- Waste Disposal & Storage
510301 - Environment
Terrestrial- Radioactive Materials Monitoring & Transport- Soil- (-1987)