Backfill as an engineered barrier for nuclear waste management. [Bentonite-hectorite]

Conference · Mon Jan 01 04:00:00 EST 1979

OSTI ID:5859651

Nowak, E J

The swelling, plastic flow, and relative impermeability of bentonite and hectorite were observed and measured after wetting with concentrated brines. Measurements of stable values of pH > 6.5 for the interstitial brines in wetted bentonite and hectorite confirmed conditions favorable for precipitation and sorption of transuranics. Values of K/sub d/ > 2000 ml/g were measured for Pu and Am. Calculated estimates of the effectiveness of a one-foot-thick backfill barrier are presented. They show that the breakthrough of Pu and other transuranics (K/sub d/ = 2000 ml/g) can be delayed for 10/sup 4/ to 10/sup 5/ years. The breakthrough of most fission products (K/sub d/ = 200 ml/g) can be delayed for 10/sup 3/ to 10/sup 4/ years, sufficient time for them to decay to very low concentrations. A backfill barrier can contribute significantly to a radioactive waste isolation system.

• Research Organization: Sandia Labs., Albuquerque, NM (USA)
• DOE Contract Number: EY-76-C-04-0789
• OSTI ID: 5859651
• Report Number(s): SAND-79-0990C; CONF-791112-42
• Country of Publication: United States
• Language: English

Related Subjects

052002* -- Nuclear Fuels-- Waste Disposal & Storage
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
ADSORPTION
BACKFILLING
BENTONITE
BRINES
CLAYS
ELEMENTS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
MANAGEMENT
MINERALS
MONTMORILLONITE
PERMEABILITY
RADIOACTIVE WASTE STORAGE
SORPTION
SORPTIVE PROPERTIES
STORAGE
SURFACE PROPERTIES
SWELLING
TRANSURANIUM ELEMENTS
WASTE MANAGEMENT
WASTE STORAGE