Slight change in properties
Over 10,000 years, a R7T7 vitrified waste package will rack up an incredible 10 to the power of 19 alpha disintegration events per gram. In the laboratory, doses of the same order of magnitude can be accumulated in just a few years by doping similar glass specimens with curium-244. The diagram shows that the volume of glass specimens subjected to such irradiation varies by only a small amount, stabilising at a value of 0.6% when 20% of the 10,000-year dose has been received. Other properties, such as the hardness, brittleness and water resistance of the glass follow a similar pattern.
CEA: "Long-term behavior of vitrified waste packages-", I. Ribet et al., Global 2009, 9038