“the results would be far worse, spreading radioactivity over an area of nearly 100 square miles.”
That’s detectable radiation. Now, what’s the area for a dangerous radiation dose? And now for one that’s over Canadian standards for “general population” exposure?
Note that neither the actual radiation dose nor initial source strength is given in this article. Only terms like “substantial” and “worse” and similar vague undefined terms.
http://www.radprocalculator.com/Gamma.aspx
Here’s a calculator that lets you figure out some of the issues. A kilocurie of Cs137 at 100 meters would expose you to about 23 millirems per hour. You’d need to stand there for 4000 hours to get a dose that would make you sick (not a lethal dose, just one that would make you ill. A 100% lethal dose would take 28,000 hours).
There are other codes that bear directly on the problem and when I get to the computer that has them I’ll post more.
An Alpha emitter of lower Specific Activity could in the long term be more fatal because of inhalation effects, such as lung and liver cancer. Thorium, for example, has a feeble Gamma associated with the decay and would be a little more difficult to detect and easier to shield, compared to Cs137 and Co60.
I worked in California in the 90’s when there was a fire at a refinery in Richmond, outside of Oakland. The fire sent lots of smoke and fumes in the air, some of irritating, but not really dangerous. Every ER in the Bay area was jammed. I worked in SACRAMENTO, nearly 80 miles away and we were JAMMED with people who “wanted to be checked out”. They had driven over an hour and a half, were fine and still wanted to be checked out. All people will need to hear is “radiation” and they will swamp the medical system demanding to be seen.