Leaching experiments on borosilicate glass frit and simulated nuclear waste glasses were performed as a preliminary to leaching experiments on glasses incorporating radioactive waste. The experimental design included (i) simulated waste glass, (ii) ASTM Grade-2 titanium container material, (iii) clay buffer material, (iv) Standard Canadian Shield Saline Solution, and (v) granitic rock.
Cumulative fractions of release for boron were determined, as well as the solution concentrations of silicon, iron, strontium and cesium. The leach rates for boron after 28 d were approximately 5x10-6 kg.m-2 .8-1 for experiments in stainless steel vessels, and 2xl0-7 kg.m-2 .s-1 in Hastelloy* vessels. There is an apparently strong relationship between the clay/groundwater ratio, the concentration of iron in the solution, and the concentrations of silicon, strontium, and cesium.