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Recent studies indicate that magnesium in seawater may help nuclear waste stored in silicate glass stay put. The preliminary results of work combining observations of the dissolution rate of ancient glass particles on land and in the oceans with laboratory experiments show that magnesium in seawater greatly retards the corrosion of silicate glasses similar in composition to those currently used to contain nuclear waste in Europe and proposed for use by the United States.

In Europe, radioactive waste is mixed and melted with silicate components to form a liquid that is then poured into stainless steel containers and quenched to a glass. The containers are buried and surrounded with clay backfill. This method is being considered for the United States, where most high-level nuclear waste is stored in liquid form. Glass is thought to be a more reliable form of storage for the long periods of time, more than 20,000 years, that radionuclides must be isolated from the environment. Until recently, there was no direct evidence on how resistant to chemical and physical attack the glasses would really be on such a time scale.