No, Chernobyl is about as worst- ase-scenario as it gets. Entire pressure vessel exploded, with no secondary containment. It was exposed to atmosphere for days (weeks?) Before being sealed.
Chernobyl was very close to being massively worse. At Chernobyl, the melting down core never came into contact with the large pool of cooling water, but it was awfully close. Had it come into contact with all that water, an enormous explosion would have resulted. Some experts say that explosion could have irradiated half of Europe.
That is from the TV show and was never a real danger to irradiate half of Europe.
> It was feared that if this mixture melted through the floor into the pool of water, the resulting steam production would further contaminate the area or even cause a steam explosion, ejecting more radioactive material from the reactor. It became necessary to drain the pool.[71] These fears ultimately proved unfounded, since corium began dripping harmlessly into the flooded bubbler pools before the water could be removed. The molten fuel hit the water and cooled into a light-brown ceramic pumice, whose low density allowed the substance to float on the water's surface.
> These fears ultimately proved unfounded, since corium began dripping harmlessly into the flooded bubbler pools before the water could be removed.
That line in the Wikipedia article seems to conflict with the book I read by Andrew Leatherbarrow "Chernobyl 01:23:40". In the book he states that if the water hadn't been drained and if the molten core had reached the water it "would have done unimaginable damage and destroyed the entire power station, including the three other reactors."
It's a shame that the Wikipedia article doesn't cite it's source on that claim. It would be interesting to reconcile the seemingly conflicting information.
If it wasn't close, as you suggest, then why did a crew of people wade into highly radioactive water -- a probable suicide mission -- to manually operate the valves to drain the water?
> That water was drained, precisely because of concerns that it would melt down and come into contact with water.
Even if the concrete base under the reactor was breached, the water underneath had been drained. In retrospect this was unnecessary, but it added another layer of precaution.
Furthermore, what makes you think a potential explosion after coming into contact with water would be "massively" worse than the original reactor explosion? In case you aren't aware, the RBMK-1000 was a water cooled reactor. The explosion happened because the temperatures inside became so high that the pressure vessel ruptured. By comparison, the contact with the water beneath the reactor hall would not be trapped in a pressure vessel and wouldn't result generate such pressure.
What actually produced the most amount of nuclear contamination was the period of time when the fuel rods were exposed to atmosphere and burned. This put large amounts of contaminants - radioactive smoke, essentially - into the atmopshere.
You are certainly entitled to your own opinion, but others who have researched Chernobyl far more extensively than you or I have concluded differently. I am primarily getting my information from Andrew Leatherbarrow's book "Chernobyl 01:23:40". In that book, he states essentially the same as I have above.
However, it's not just Andrew Leatherbarrow who thinks so. All it takes is a simple Google search and you'll find reputable research papers hosted by the IAEA whose primary conclusion is that the accident could have been much worse. Here's one example: https://inis.iaea.org/search/search.aspx?orig_q=RN:18009127
Popular books have the incentive to garner sales - often through dramatization - not report accurate findings. Furthermore, the paper you linked was talking about wind directions not about whether the molten rods reached the cooling water underneath the reactor room floor.
> Furthermore, the paper you linked was talking about wind directions not about whether the molten rods reached the cooling water underneath the reactor room floor.
I did not say that the IAEA paper was about molten rods hitting the coolant water. There is more than one way that Chernobyl could have been much much worse. According to the paper, different wind and rainfall could have made the disaster 200-400x worse in terms of radiation consequences to humans. To say that is significantly worse would be an understatement.
> Popular books have the incentive to garner sales - often through dramatization - not report accurate findings.
It seems like you've made up your mind and no amount of evidence to the contrary will change it. I don't think I'll bother to continue participating in this line of discussion.
> why did a crew of people wade into highly radioactive water -- a probable suicide mission
This is a common myth (probably recently propagated by the scare-mongering TV series), but that mission was perfectly safe. Three men, equipped with dos meters, waded into the water and opened a valve, that was it. One died of a heart attack at 65 and the other 2 are still alive.
Furthermore, the operation was in the end unnecessary: there was no risk of such an explosion.
I'm getting my information from the book written by Andrew Leatherbarrow "Chernobyl 01:23:40" -- not a TV series. Yes, according to him they are still alive. It was indeed a probable suicide mission because all of them went in there knowing full well there was a significant chance that they would die from it.
So, considering that all three of them lived, was it that they got exceedingly lucky, or was their risk assessment just way off?
I guess the point is that it doesn't matter; if you believe something to be a probable suicide mission, then you don't do it unless you are very afraid that a disaster will otherwise occur.
But then you also have to question if their assessment of the risk of further disaster was also correct. But I guess subsequent studies have confirmed that high level of risk?
I always get a chuckle when people insist that the water under the core posed such a serious threat, given that the original reactor failure was caused by boiling water. The reactor failed after the water temperatures produced too much pressure for the pressure vessel to handle. This exposed fuel rods to atmosphere, at which point they started to burn. This is what produced the most severe contamination (that, plus debris from the reactor being ejected).
To stop this, loads of sand, boron, and lead were piled onto the ruptured reactor, eventually burying it. The concern is that the molten fuel rods underneath this blanket of material would melt through the concrete below and come into contact with water. But with no pressure vessel to contain the boiling water, it would not produced nearly as much pressure as the original failure.
