> the lab was the location of one of the nation's largest — and least known — nuclear accidents that occurred 1959 when one of the facility's ten sodium nuclear reactors experienced a partial meltdown, releasing enormous amounts of radiation into the surrounding environment.
https://spectrum.ieee.org/fun-and-uranium-for-the-whole-family-in-this-1950s-science-kit
The safety of nuclear energy is something regulated by the NRC. I have never heard anyone accusing the NRC for being lax.
Here’s a link with the NRC approval of NuScale’s SMR reactor
https://www.nrc.gov/reactors/new-reactors/smr/nuscale.html
https://www.nrc.gov/reactors/new-reactors/new-licensing-file...
A very conservative estimate would put the regulatory effort at a few hundred thousand man-hours of work, and the work on NuScale’s side to be in the millions of man-hours.
On 26 July 1994, two scientists, Otto K. Heiney and Larry A. Pugh were killed when the chemicals they were illegally burning in open pits exploded. “
… I think there’s more here than just the reactor meltdown.
And also, this was in 1959. Compare that to https://en.m.wikipedia.org/wiki/Springhill_mining_disasters. “Safe” is relative