Why we should say NO to
nuclear power

4. Because the problem of radioactive waste remains unresolved

Operating a nuclear reactor produces radioactive waste. This is not a simple product. Just as the flue gas from a coal-fired power station is a complicated mix of many different compounds, the used fuel rods from a nuclear reactor contain a complex mixture of radioactive isotopes. The exact composition of the mixture depends on the configuration of the reactor and the way it is operated.

As mentioned earlier, some reactors, like Calder Hall in the United Kingdom, were specifically designed and operated to maximise production of plutonium, the raw material of choice for weapons. Commercial power reactors are usually designed and operated to maximise electricity production, so they yield a different cocktail of by-products.

In every case, the used fuel rods are both intensely radioactive and very hot, so they require skilful and careful handling. Usually they are stored under water at the reactor site until the short-lived isotopes have decayed and radiation levels have fallen. Sometimes the rods are re-processed to recover fissile material that can be re-used in power stations or turned into weapons. One way or another, the end result is a mix of waste products that is dangerously radioactive.

They need to be stored away from the biosphere for very long periods of time, certainly tens of thousands of years, arguably much longer. This is a huge technical challenge. Nothing humans have built has lasted this long. It is also an enormous challenge to our social institutions. No human society has ever lasted as long as the waste storage systems need to endure. We need to be confident that the storage is not just technically robust but also proof against unforeseeable changes in the social structure.

When I was working in the United Kingdom, nuclear agencies in the northern hemisphere were talking glibly about storing the waste in blocks of glass. As a scientist, I was horrified by this idea. Glass is not really a solid, it is technically a super-cooled liquid, which means it is not stable in the long term even at normal temperatures. It was absurd to suppose that it could remain stable for geological time when subjected to heat and intense radiation.

The usual defence was to say that the blocks of glass would be encased in some other material that would reduce the chance of the radioactive elements escaping. That is certainly an improvement, but the whole approach was still a worry. It has so worried local communities that nobody has been very keen to have waste stored in their area.

The British government conducted an intensive study to find stable geological strata like salt beds or very old granite in which a waste storage facility could be located, but in every case the hostility of the local community caused the government of the day to back off.

For decades the United States planned to store its waste in a site with the wonderfully apposite name of Yucca Mountain in Nevada, but that scheme was recently cancelled. Even Nevada, arguably the gambling capital of the world, would not take a punt on nuclear waste! After spending an estimated US$9 billion on the project, the United States is now back at square one, setting up an advisory committee to make recommendations.

Some in Australia believe the country has a moral obligation to take in radioactive waste, having made money by selling uranium in the first place. Others see it as an opportunity to make more money by charging to take back the waste Australia has indirectly created.

It is true that Australia is an old and extensively weathered continent, so some of our rocks are as suitable for waste storage as those anywhere. But nobody really wants the waste in their back yard. The Australian government was forced to back off a proposal to store low-level radioactive waste in the South Australian desert because of bitter community opposition – even in a State that is quite happy to mine and export uranium.

The Australian Government is also interested in dumping radioactive waste in the Northern Territory. The former Howard government’s Radioactive Waste Management Act allows the national government to over-ride local law and impose waste on the Northern Territory. The present federal government is investigating four possible sites – three on Defence Department properties and one on land belonging to indigenous Australians.

The Australian government is already meeting community opposition to disposing of low-level waste, most of it from the Lucas Heights reactor in Sydney. There is certain to be far greater opposition to any proposal to store nuclear waste from power stations anywhere in Australia because such waste would be much more dangerous than the low-level material.

I think the adage, nature knows best, is appropriate here. An Australian professor of geology, the late Ted Ringwood, had the insight that radioactive elements are locked up over geological time in naturally occurring rocks: the ore bodies from which uranium is extracted.

He proposed producing a synthetic rock, called “synroc” for short, in which waste could be stored. We know that these rocks are stable over geological time, so that could be a solution.

ANSTO did preliminary studies that showed it is possible to produce synroc and imprison waste in it. Some of my scientific colleagues at Griffith University studied the stability of the new material and found it was many times better than glass at resisting possible attack by hot groundwater. It looked like a possible solution to the perennial problem of safely storing waste. Yet no nuclear agencies have yet adopted the new technology.

I believe this is because after assuring politicians for decades that glass is perfectly acceptable, they are now reluctant to admit there is a better approach. It is a reminder that the problem of storing radioactive waste is not just a technical challenge, but also places huge demands on our political systems and social institutions. So far, they have not been up to those demands.

A related issue is the de-commissioning of nuclear power stations at the end of their useful life. Again, nobody has yet completed the task of de-commissioning a large nuclear power reactor. Estimates of the likely cost vary widely, from about US$300 million in the United States to about a billion pounds in the United Kingdom – in our dollars, from about $330 million to about six times as much. France has set aside over A$100 billion for studies of decommissioning and waste management, but there is still no credible solution.8

Nuclear power stations have been producing radioactive waste for over 50 years. It now amounts to more than 250 million tonnes, with 10,000 tonnes intensely radioactive. Despite this huge and growing problem, nobody has yet established a system for safely disposing of the waste. Some in the industry say there is no hurry, that we have plenty of time. But the longer the problem remains unresolved, the more sceptical we might reasonably be about whether there is a viable solution. This is a fundamental moral issue: to produce waste for which there is no proven treatment or storage is to impose an unacceptable burden on future generations.