The Safe Disposal of Nuclear Waste
Quirk, Tom, Review - Institute of Public Affairs
The most significant practical issue in nuclear electricity generation is the issue of nuclear waste. Regardless of the political or economic factors in the debate over nuclear power, the question of waste disposal is a legitimate and timely one. A safe, long-term solution is needed for Australia and the world.
On even the most conservative projections, the use of nuclear power is likely to increase over the next few decades. On top of that, there is also a large stockpile of nuclear waste from power stations and nuclear weapons which needs permanent disposal. Many countries simply do not have the geological, political, economic and administrative capacity to store their waste safely and durably.
Australia may be in a unique postion to offer safe long-term burial of waste. The key element is the development of an internationally accepted and approved high-isolation disposal site that would be unique. The waste management system would include a disposal site, a railway and the associated seaport docking facilities.
The problem of long-term disposal of radioactive waste affects all developed countries. Even countries without nuclear power or research reactors use radioactive isotopes for medical and industrial purposes, and these isotopes must be safely stored until their levels of radioactivity are no longer dangerous. Countries which produce nuclear energy or have research reactors (such as Australia), face an even greater challenge because nuclear reactors produce waste which has very high initial levels of radioactivity. The time needed for safe disposal is neatly illustrated below. High-level waste takes at least 5,000 years before its activity becomes similar to that of a uranium orebody. Thus, waste needs to be safely isolated for extremely long times, up to a million years, if the highest standards of radiation safety are to be met.
Nuclear power utilities throughout the world have already produced 270,000 tonnes of spent nuclear fuel. During the next 25 years, this inventory will increase by approximately 12,000 tonnes annually, assuming that no new power plants are constructed.
Every country that has reviewed the problem of long-term disposal of its radioactive waste has reached the same conclusion: for the greatest long-term security, their wastes should be placed in a geologically stable underground repository. Such a repository is typically designed much like an underground mine, with ramps or shafts and elevators to access the underground workings, and waste packages inserted into the walls or floors of excavated tunnels. The repository protects people against direct exposure to radiation from the unwanted nuclear materials and must be sited and designed so that there will be no accidental escape of significant amounts of radioactivity to the point where humans or animals might be exposed.
Since the 1960s, extensive research programmes have been underway to develop the technology required to identify and characterize suitable disposal sites, to encapsulate and store the wastes, and to demonstrate the long-term safety of a disposal facility. With few exceptions, the scientists and engineers involved in these programmes have concluded that the technology exists to dispose of these wastes safely.
Despite these efforts, however, no repositories for disposal of spent nuclear fuel or high-level waste have been constructed. Additionally, the majority of the public believes that the problems of disposing of radioactive waste have not been solved and that radioactive wastes represent a serious threat to the environment. Why is there such a discrepancy between the opinions of informed scientists and those of the public? One reason for this lack of public confidence lies in distrust of the necessarily untried technological solutions that are being proposed for the different disposal programmes. While most scientists have confidence that all of the key questions have been answered, the public is not yet convinced. …