In the 70 year history of the development and use of atomic energy numerous problems have developed. We can easily argue that most of these problems should have been foreseen, and while that may offer us an opportunity for serious reflection, that won’t be a focus in this post. What I would like to do here is to review the location and times at which important nuclear actions or accidents have occurred leading to significant contamination of the environment and in some cases of the entire Earth. I’m going to look at most of these cases in summary form and perhaps talk about some of them in additional detail in later posts on this blog.
Two older sites which were developed during or shortly after World War II, one at Chelybinsk (Mayak) in Russia in the Ural mountains, and the other at Hanford in the state of Washington in America. The former was initially used to purify Uranium and operated for that purpose from 1948 – 1957. Initially there were no technical people present at the site and liquid radioactive waste was simply dumped into the river which has eventually led to high level contamination of the associated river system. Later, wastes were stored in silos.
In 1957 an explosion occurred at one of the storage sites leading to the release of about one billion Curies of radioactive fallout. This is about twice the amount released during the 1986 explosion of the reactor at Chernobyl, but we’ll come back to that. In 1967, at Chelybinsk, one of the lakes where radioactivity had been dumped dried up. Many of the radioactive sediments we’re then spread by the winds over great distances, but mainly over the surrounding 22,000 square kilometers. Overall contamination of the Chelybinsk area was concentrated over the local area, where the cancer rate grew to about four times the Russian average which was already high. In addition, male life expectancy in this region is 57.
The Hanford site, which was used initially to make plutonium as part of the Manhattan Project and later to make weapons grade plutonium during the Cold War. The site was decommissioned afterward. Just as in the case of Chelybinsk safety procedures were inadequate and much radioactive waste was released into the nearby rivers that led into the Columbia river. Still at the “decommissioned” site there are 53 million gallons of high level radioactive waste, 25 million cubic feet of solid radioactive waste, and about 200 square miles of radioactive contamination beneath the site with apparently more being discovered all the time. Hanford has about two-thirds the total nuclear waste in the continental U.S. Overall, the pace of the clean up, which has been underway for about two decades, is proceeding slowly and costs continue to increase.
Both Chelybinsk and Hanford represent aberrations, although the dangers of radioactivity were known shortly after World War II was concluded, and it’s difficult to see how even in retrospect serious safety measures were not enacted sooner as the world began constructing nuclear power plants for peace time use.
At least three serious accidents have occurred at nuclear power generating facilities since the 1960s. One was relatively minor while the other two were quite serious and suggest that we have on our hands a technology which we may not be able to control long-term.
First, the Three Mile Island partial core meltdown was brought under control rather quickly even though some radioactivity was released locally. In relative terms the amounts released were minor and there may have been few human lives affected. The reactor was subsequently completely decommissioned.
The first really serious modern nuclear power facility accident was at Chernobyl in 1986. On the order of 500 million Curies of radioactivity was released. The fire at the main reactor raged for days and substantial amounts of radioactivity were dispersed throughout the world. It is estimated that about 500 million Curies of radioactive nuclides were dispersed locally in Bellarus, Ukraine and Russia with lesser but still substantial radioactivity dispersed throughout Europe and Asia. Total radioactive fallout greatly exceeds the amounts released in Hiroshima and Nagasaki by hundreds of times. It was estimated that about one percent of the radioactity from Chernobyl reached North America, which would mean that if evenly distributed would have resulted in a little less that a Curie of radioactive fallout per square mile. While deaths due to Chernobyl have been estimated by the International Atomic Energy Association to be in the range of 4,000, other studies claim the number so far to be closer to one million and climbing. We’ll come back to this point in a later post.
Finally, the release of radioactivity by the Fukushima meltdown was substantially less that that seen at Chernobyl, as the situation was brought under control more quickly. The Fukushima disaster was due to a loss of cooling capacity of the reactors subsequent to the failure of the generators after the tsunami. However, the Fukushima facility is unusual in that several of the reactors have partially melted down and they are going to be difficult to decomission. Efforts are underway, but the estimated time required to completely decommission the site is about 40 years. Until then the affected reactors will need to be cooled and the radioactive waste dealt with until the decommissioning process is completed.