Not this mess, or even that one, really. The "bio-robots", so called by their masters, were mainly collecting debris from the reactor explosion for containment; they were not trying to deal with the core slag sunk into the basement of the building, which at that time was still thermally very hot as well as being ferociously active. Even to approach that would have been immediately lethal.
Given the cited dose rate, the same is true at Fukushima - an acute dose of 10Sv is very likely lethal on its own, and at 650Sv/h you get more than that every minute. Anyone you send into that is going to be unable to work within seconds, and dead inside a couple of minutes tops.
That's good to know, thanks. On the other hand, I find sources calling that dose rate lethal within minutes, and at least some of the Fukushima corium is roughly seven times as active. Even if you're willing to write off as many lives as it takes to reduce what is essentially solidified lava by means of hand tools into a containable form, I doubt it's likely to succeed simply because it'll kill off your workers so fast that, after a little while, no further progress is possible because of all the corpses blocking the way.
Well I mentioned it just as an example of humans being better at it than robots. I don't really imply that sending people to death is a good idea.
We should also distinguish between site cleanup (which is certainly impossible) and secure containment (which is possible and was done before). The idea is not to chip away bits of highly radioactive substance, but find a safe way around it to isolate the world from further contamination. Apparently, not everyone is convinced Japan has a plan there.
Not this mess, or even that one, really. The "bio-robots", so called by their masters, were mainly collecting debris from the reactor explosion for containment; they were not trying to deal with the core slag sunk into the basement of the building, which at that time was still thermally very hot as well as being ferociously active. Even to approach that would have been immediately lethal.
Given the cited dose rate, the same is true at Fukushima - an acute dose of 10Sv is very likely lethal on its own, and at 650Sv/h you get more than that every minute. Anyone you send into that is going to be unable to work within seconds, and dead inside a couple of minutes tops.