Nuclear reactions are smoldering again at Chernobyl

[Ostfriese]

Originally Posted by 3catcircus

Likely not. Any fission would likely be short-lived, resulting in the critical mass/geometry melting or shifting, becoming subcritical again.

You need to remember that the core has flowed all over the basement as molten corium, so any portions that could fission again are much further away from having enough mass in the right geometry.

I doubt that there's any chance to achieve critical mass due to shifts/melting and a self-sustained chain reaction as a consequence of this. It would require quite pure amounts of fissible material melting/shifting together, and after 35 years of decaying there shouldn't be much material that can be considered "pure" left - and that's before considering that the corium is a wild mixture of fuel rods, remains of the control rods, concrete, steel, zirconium, sand and soil, among other things.


The article mentions "irradiated uranium", which is pretty strange and suggests that the writer doesn't know enough about the topic. Uranium is always radioactive, it doesn't have any stable isotopes, and it cannot be irradiated.



There could be a variety of reasons for the increased neutron count, starting with recently opened leaks/cracks, which would allow water or steam to pass through and carry radioactive material into the range of the sensors.