• Collection |

    Glass has proven itself to be a chemically durable wasteform for immobilization of radioactive waste. However, high levels of radioactivity generated by glassy wasteforms will persist over extensive time scales, requiring long-term isolation from the environment. During this time, glass will undergo chemical attack by groundwater, radiation damage, and mechanical stress, which eventually could result in release of the radionuclides into the environment. It is therefore vital to understand the degradation mechanisms at play, so that glass compositions can be created that safely immobilize radionuclides over hundreds of thousands of years. Towards this goal, International Simple Glass is a model six oxide borosilicate glass studied worldwide to better understand glass corrosion in aqueous environments. This reference material was made several years ago by the nuclear glass community to seek a consensus on the mechanisms controlling the long-term dissolution rate of glass used to immobilize radioactive waste. This collection of papers in npj Materials Degradation reports recent understanding of International Simple Glass and highlights the diversity of scientific problems related to understanding its degradation, and the wealth of methods and approaches to tackle them.