NUCLEAR WASTE DISPOSAL IN THE UNITED STATES AND ELSEWHERE: SUCCESSES AND FAILURES

Although nuclear power has generated electricity for over half a century, most countries with this technology still struggle to find a solution to the high-level radioactive waste it generates. Only Finland, Sweden, and France seem close to a solution. The rest, including the United States, are many decades away from a final solution. There is general agreement that some type of geologic disposal, in a deep repository, is the best method for disposition of spent nuclear fuel and the high-level wastes from the reprocessing of spent nuclear fuel. Over the past three decades, geoscientists have significantly contributed to our understanding of how repositories and the wastes contained within them will behave over time, including the importance of the geochemical environment the waste is exposed to, the behavior of the waste form, and the method by which a potential repository is evaluated. We now understand that, if given the opportunity, we can tailor waste forms to retain the actinide elements within them for many millions of years, given a particular geologic repository environment. We also understand that waste forms such as spent nuclear fuel (essentially uranium dioxide) perform best in a chemically reducing environment. Finally, the way in which countries decide whether a particular repository site will perform adequately over time is a policy decision that must be informed by science, but most countries now understand that multiple sources of evidence must be relied upon, and models of repository performance can only be relied upon for the near-term and not the long-term.