There was a report, at that time, that the melting uranium mixed with water would go critical, as water would become a moderator not that it was flash into stea

There was a report, at that time, that the melting uranium mixed with water would go critical, as water would become a moderator not that it was flash into steam. The estimated yield was in the megaton range. It probably was a bad report, just a 'worst case scenario', but the meeting, depicted in the series, where it was discussed could have happened with probably different participants. I see it as very similar to the fears that the trinity test would have caused the nitrogen in the atmosphere to undergo a fusion chain reaction. Even though those fears weren't realistic, they were real and are often included in the telling of the history of the Manhattan project. "And if the uranium reached meltdown temperature - 2,900C -a single sphere of molten fuel would burn through the concrete foundations of the reactor building, and keep going until it reached the water table. At that moment, there would be another explosion, exponentially more devastating than the first; the three remaining reactors would be destroyed in a nuclear blast that would render Ukraine, Belarus and Russia uninhabitable for decades to come. 'That was the most terrifying thing,' says Veniamin Prianichnikov. 'We were petrified of meltdown, walking around like zombies.'" https://www.theguardian.com/world/2006/mar/26/nuclear.russia https://www.theguardian.com/world/2006/mar/26/nuclear.russia "There was a moment when there was the danger of a nuclear explosion, and they had to get the water out from under the reactor, so that a mixture of uranium and graphite wouldn't get into it - with the water, they would have formed a critical mass. The explosion would have been between three and five megatons. This would have meant that not only Kiev and Minsk, but a large part of Europe would have been uninhabitable. Can you imagine it? A European catastrophe." Sergei Vasilyevich Sobolev Deputy head of the executive committee of the Shield of Chernobyl Association https://www.theguardian.com/environment/2005/apr/25/energy.ukraine#_=_ https://www.theguardian.com/environment/2005/apr/25/energy.u...