Properties of slag concrete for low-level waste containment

Conference · Tue Jan 01 00:00:00 EST 1991

OSTI ID:5249528

Langton, C A ^[1]; Wong, P B ^[2]

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1. Westinghouse Savannah River Co., Aiken, SC (United States)
2. Bechtel National, Inc., Aiken, SC (United States)

Ground granulated blast furnace slag was incorporated in the concrete mix used for construction of low-level radioactive waste disposal vaults. The vaults were constructed as six 100 {times} 100 {times} 25 ft cells with each cell sharing internal walls with the two adjacent cells. The vaults were designed to contain a low-level radioactive wasteform called saltstone and to isolate the saltstone from the environment until the landfill is closed. Closure involves backfilling with native soil, installation of clay cap, and run-off control. The design criteria for the slag-substituted concrete included compressive strength, 4000 psi after 28 days; slump, 6 inch; permeability, less than 10{sup {minus}7} cm/sec; and effective nitrate, chromium and technetium diffusivities of 10{sup {minus}8}, 10{sup {minus}12} and 10{sup {minus}12} cm{sup 2}/sec, respectively. The reducing capacity of the slag resulted in chemically reducing Cr{sup +6} to Cr{sup +3} and Tc{sup +7} to Tc{sup +4} and subsequent precipitation of the respective hydroxides in the alkaline pore solution. Consequently, the concrete vault enhances containment of otherwise mobile waste ions and contributes to the overall protection of the groundwater at the disposal site.

• Research Organization: Westinghouse Savannah River Co., Aiken, SC (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC09-89SR18035
• OSTI ID: 5249528
• Report Number(s): WSRC-MS-91-073; CONF-9103238-1; ON: DE92013194
• Resource Relation: Conference: American Concrete Institute (ACI) spring meeting, Boston, MA (United States), 17-21 Mar 1991
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
36 MATERIALS SCIENCE
CONCRETES
MECHANICAL PROPERTIES
MIXTURES
LOW-LEVEL RADIOACTIVE WASTES
RADIOACTIVE WASTE DISPOSAL
RADIOACTIVE WASTE FACILITIES
SLAGS
WASTE PRODUCT UTILIZATION
BINDERS
COMPRESSION STRENGTH
CRACKS
DIFFUSION BARRIERS
LEACHING
SAVANNAH RIVER PLANT
BUILDING MATERIALS
DISPERSIONS
DISSOLUTION
MANAGEMENT
MATERIALS
NATIONAL ORGANIZATIONS
NUCLEAR FACILITIES
RADIOACTIVE MATERIALS
RADIOACTIVE WASTE MANAGEMENT
RADIOACTIVE WASTES
SEPARATION PROCESSES
US AEC
US DOE
US ERDA
US ORGANIZATIONS
WASTE DISPOSAL
WASTE MANAGEMENT
WASTES
052002* - Nuclear Fuels- Waste Disposal & Storage
360603 - Materials- Properties