Three Mile Island's recent fourth anniversary was an occasion to rehash what many commentators call the worst nuclear-reactor accident on record in the Western world. They picked the wrong accident and the wrong anniversary.
They forget the fire in one of two military reactors at Britain's Windscale plutonium facility in 1957. Three Mile Island (TMI) resulted in no public danger. The Windscale fire spread dangerous radioactive material over Britain to an extent that only now is beginning to be appreciated.
The lesson of TMI was that lax management, inadequate regulation, and poor operator training were a potential danger within the civilian nuclear power system of the United States. The lesson now emerging from the Windscale incident is the danger of excessive military secrecy that hides vital information from regulators responsible for public safety.
As far as TMI is concerned, both the presidential commission chaired by John G. Kemeny and the Nuclear Regulatory Commission's panel found there was no significant radioactive contamination. The only radioactive materials released were chemically inert gases. These quickly dispersed. They could not be absorbed by plants, humans, or other animals. There was no danger of a meltdown. Even had this occurred, the plant's foundation would have contained the fuel, allowing it to resolidify without contaminating the environment. There was no danger of a hydrogen explosion. Although hydrogen did accumulate at the top of the reactor vessel, its presence inhibited release of oxygen, which is needed for hydrogen to burn or explode.
In short, TMI dramatized important management and regulatory shortcomings, but presented no public danger. The Windscale fire was quite different. It released radioactive iodine, which accumulates in human thyroid glands. It now appears that other dangerous radioactive material - polonium - also was released.
Radio-iodine contamination was admitted at the time, although its threat was minimized by officials. Milk from cows grazing over some 500 square kilometers in the vicinity of Windscale was destroyed. This was officially represented as erring on the cautious side. However, Britain's National Radiological Protection Board (NRPB) now disagrees.
In Britain, responsibility for radiological safety is vested in an agency independent of the Atomic Energy Authority, which develops nuclear technology, and of the governmental operating company, British Nuclear Fuels Ltd., which runs Windscale. In February of this year the NRPB issued a study that concluded that the milk ban had only reduced the British population's overall radio-iodine exposure by 12 percent. It criticized the old Windscale investigation for considering only the risk to the local population rather than to Britain as a whole.
Since then, a more disturbing claim has emerged. John Urquhart of Newcastle University published a critique in New Scientist reporting that polonium, a dangerous radioactive element then used to make nuclear weapons, also was released. The official report on Windscale said nothing of this. Although an NRPB official did mention it in a paper at the United Nations 1958 Atoms for Peace Conference, he did not say how much was released. His remarks seem to have been soon forgotten.
The implication, according to Urquhart and New Scientist, is that officials wanted to keep the manufacture of polonium secret, because the material was needed for hydrogen bomb tests. New Scientist reports that the NRPB staff was unaware of the polonium release when it made its recent study. The agency is reassessing the Windscale incident. It disagrees with Urquhart's conclusion that the polonium was a significant health hazard. But its new research hasn't yet been published. Thus, at this writing, the issue is far from settled.
Whatever the polonium hazard may have been, it now seems clear that there was a coverup that prevented full and proper public assessment of the Windscale danger at the time. Compared to this kind of official deceit, the confusion that surrounded the TMI incident seems trivial. Calculators and math skills
Remember the fuss about letting school children use calculators? There was wide concern that this would cripple math skills. A West German study now indicates this concern was misplaced. It says the calculators have little impact , good or bad.
The three-year study involved some 11,000 pupil tests and 500 teacher questionnaires in Dortmund. Spot checks in Bonn and some smaller towns confirmed the study's results. Among calculator-using students in classes 7 to 9, math skills ran the full range from poor to excellent. Compared to noncalculator users, there seemed little difference.