Abstract
Bentonite has been proposed as a primary material for sealing shafts of nuclear waste repositories. It possesses low permeability, chemical and physical stability, and compatibility with most host rock masses and groundwater chemistries. This paper investigates the construction properties of bentonite and evaluates the use of dynamic compaction in constructing an effective bentonite shaft seal. Extensive laboratory tests of dynamic compaction have been conducted to study the densification of granular bentonite mixed with distilled deionized water or with brine from the Waste Isolation Pilot Plant (WIPP). Results of the dynamic compaction investigations delineate the influence of moisture content, compactive energy, mixed brine content, lift thickness, and rammer weight on the achievable dry density. Dynamic compaction can densify bentonite to a dry density of 1.86 Mg/m 3 when mixed with WIPP brine and 1.74 Mg/m 3 when mixed with distilled deionized water. At these densities bentonite exhibits permeabilities on the order of 1.0×10 −19 m 2 .
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
