Designer of Reactor Containment Vessel: Potential for Many "Chernobyls"

BBC reports:

Japanese engineer Masashi Goto, who helped design the containment vessel for Fukushima's reactor core, says the design was not enough to withstand earthquakes or tsunami ...

Goto also said:

“It is difficult to say, but that would be a core meltdown. If the rods fall and mix with water, the result would be an explosion of solid material like a volcano spreading radioactive material. Steam or a hydrogen explosion caused by the mix would spread radioactive waste more than 50km. Also, this would be multiplied. There are many reactors in the area so there would be many Chernobyls.

Goto accused the Japanese government of deliberately withholding vital information that would allow outside experts help solve the problems:

For example, there has not been enough information about the hydrogen being vented. We don’t know how much was vented and how radioactive it was.