All that don't matter one bit if some of the corium flowed down the drywell sumps and out into the downcomers. And Tepco sure wont tell you if that actually occurred.
What you are actually reading is the best case scenario.
if some of the corium flowed down the drywell sumps and out into the downcomers
The point of the blog post provided for your reading pleasure and education was the consequence of corium outside the BWR reactor vessel. Look closely at how the
reactor building is configured for a Mark I Containment. Do you see what they label "downcomer"? There is a second downcomer inside the reactor vessel between the core barrel and the reactor wall (where the jet pumps are). The drywell is immediately outside the reactor vessel (do you see that in the illustration
provided?) -- the drywell sump is directly below the lower head of the reactor vessel. The bottom of the upside-down-light-bulb shaped drywell is filled with concrete. Then you reach the steel liner that is the upside-down-light-bulb itself. Then you start into the foundation of the reactor building supporting the 700 ton reactor vessel and all of the other equipment in the reactor building. The foundation is over twelve feet thick by itself. Now read the comment you posted. Does it make any sense??? I have to say that I have rarely read anything on FR as ignorant as the comment you wrote above. If you do work at an n-plant, then you need to think about a new line of work.
