Transport parameters in bentonite and candidate repository host rocks

Conference · Fri Nov 01 04:00:00 EST 1991 · Transactions of the American Nuclear Society; (United States)

OSTI ID:5092019

Conca, J L

Transport parameters (diffusion coefficients D({theta}), hydraulic conductivities K({theta}), and retardation factors R{sub f}) are being experimentally determined in materials relevant to the proposed high-level nuclear waste repository in Japan. The materials are compacted bentonite, which will be used as a backfill material around the canisters, and whole rock from the four candidate host rock environments (granite, basalt, tuff, and mudstone). Knowledge of D({theta}) and K({theta}) as a function of the volumetric water content {theta} is particularly important in the near-field transition zone around waste packages where changes in temperature, water content and composition, compaction of backfill, infiltration of fines, and secondary mineralization will alter the transport character of near-field environments. The transport parameters are being investigated using a new flow technology, the Unsaturated Flow Apparatus (UFA{trademark}), that overcomes some of the experimental difficulties involved with investigating low-conductivity materials by combining the larger driving forces obtainable with centrifugation techniques with precision fluid flow through a rotating seal. Once the water content is fixed at the target value and the system has achieved hydraulic steady state, transport parameters are determined from associated methods.

• OSTI ID: 5092019
• Report Number(s): CONF-911107--
• Conference Information: Journal Name: Transactions of the American Nuclear Society; (United States) Journal Volume: 64
• Country of Publication: United States
• Language: English

Related Subjects

052002* -- Nuclear Fuels-- Waste Disposal & Storage
053001 -- Nuclear Fuels-- Environmental Aspects-- Siting-- (1992-)
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
54 ENVIRONMENTAL SCIENCES
540230 -- Environment
Terrestrial-- Radioactive Materials Monitoring & Transport-- (1990-)
ASIA
BACKFILLING
BASALT
BENTONITE
CENTRIFUGATION
CLAYS
DEVELOPED COUNTRIES
DIFFUSION
ENVIRONMENTAL TRANSPORT
GRANITES
HIGH-LEVEL RADIOACTIVE WASTES
HYDRAULIC CONDUCTIVITY
IGNEOUS ROCKS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
JAPAN
MANAGEMENT
MASS TRANSFER
MATERIALS
PACKAGING
PLUTONIC ROCKS
RADIOACTIVE MATERIALS
RADIOACTIVE WASTE DISPOSAL
RADIOACTIVE WASTE MANAGEMENT
RADIOACTIVE WASTES
RADIONUCLIDE MIGRATION
ROCKS
SEDIMENTARY ROCKS
SEPARATION PROCESSES
SILTSTONES
STEADY-STATE CONDITIONS
TUFF
VOLCANIC ROCKS
WASTE DISPOSAL
WASTE MANAGEMENT
WASTES