Can we fix nuclear energy?

Abstract

A 1 million kW pressurized water reactor contains 15 billion Ci radioactivity. This is about equal to the natural radioactivity in all the oceans; radioactivity that accompanies the decay of the 4 billion tons of uranium and its daughters dissolved in the seas. Nothing except time can turn radioactivity off. The radiation from an X-ray machine ceases when the technician turns the machine off. By contrast, the radioactivity in a reactor decays only .slowly after the reactor is shut off; it contributes about 200,000 kW heat while the reactor is running and, depending upon how long the reactor has been running before shutdown, is still generating 8500 kW a week later from the remaining 2 billion Ci. A large chain reactor must therefore be cooled even after the reaction has ceased or the fuel will melt. If it melts, radioactivity will excape from the fuel. From the beginning in 1942, all of us at Arthur Compton's Metallurgical Laboratory in Chicago where the first chain reaction was established sensed that mankind was crossing a threshold when he learned howqo create at will radioactivity on an enormous scale. Up until then radioactivity was measured in pCi or mCi--I g radium, costing $50,000, was equal to I Ci. Enrico Fermi, the developer of the chain reactor and our scientific leader, on occasion would remind us of this. It was not only the bomb that changed things--it was also the creation of unimaginably large amounts o.f radioactivity. It is no wonder that from the very beginning safety was an obsession among the developers of nuclear energy. My first job at Chicago was to help Edward Teller estimate how much radioactive carbon would be spewed into the atmosphere from a small aircooled reactor we were planning to build at Oak Ridge. And it was Edward Teller, more than anyone else, who insisted that the safety of reactors must predominate. He was the founder, and first chairman in 1948, of what is now called the Advisory Committee on Reactor Safety (ACRS). No reactor could be built