Dear Dr. Zoomie – What’s this I hear about a Boy Scout building a nuclear reactor in his back yard? Is this for real? And if a Boy Scout can build a reactor, how hard can it be? How much risk were his neighbors in?
Well…the short version is he tried but failed, it’s very difficult, and his neighbors were at little to no risk. But where would the fun be if we stopped there? Here’s a little more information! And I should add that, in a number of radiological incidents I have responded to, while I have only once run across anyone trying to start a nuclear reaction, this was a scenario I was always aware of!
We spend a lot of time worrying about a malicious terrorist attack, but even well-intentioned citizens can cause problems. In 1994 government officials learned that an overly enthusiastic boy scout, trying to develop a breeder reactor in his mother’s gardening shed, had collected a huge variety of radioactive materials and contaminated the shed and parts of the yard. Not only that, but some of his experiments may have produced neutron radiation, which are not only more dangerous than beta or gamma radiation, but which can cause stable atoms to become radioactive. One lesson that can be learned is that even apparent model citizens can cause significant radiological problems.
What happened:
In 1994 David Hahn, a high school student and Boy Scout, decided to try to build a nuclear reactor that would produce reactor fuel as it operated –a breeder reactor. Hahn collected consumer products that produce alpha radiation – gas lantern mantles, smoke detectors, and so forth – and used the alpha radiation to produce neutrons. His plans were to use this neutron generator to produce fissionable uranium from the thorium in the gas lantern mantles. Unfortunately, he didn’t understand the basic physics and chemistry behind what he was trying to do – while his general reasoning was not bad, his scientific technique was lacking. Instead of producing uranium he only contaminated his mother’s car and her gardening shed.
Nuclide(s) and activity:
Primarily americium-241 and thorium-232; the activity involved is unknown.
Response efforts:
The Environmental Protection Agency was called to clean up radioactive contamination in the shed. A total of 39 barrels of radioactive waste were taken to Utah for disposal.
Health effects:
None that are known of, although Hahn might have been exposed to levels of thorium that exceeded permissible levels (he refused to be surveyed for thorium uptake).
Other impacts:
None were noted.