Effect of groundwater on the dissolution rate of the simulated nuclear waste glass SON68 under gamma irradiation

The leaching behaviour of the inactive reference of the R7T7 glass is investigated here in a synthetic clayey groundwater solution, focusing on the effect of gamma irradiation on this residual alteration rate, under static conditions, at 90 degrees C. Results don't underline any significant effect of gamma irradiation on the residual alteration rate up to 5 kGy/h, compared to experiments performed out of irradiation in groundwater or in pure water. Moreover, the evolution of boron releases in groundwater versus time is similar whatever the dose rate. These observations are consistent with SEM characterizations. (authors)