Over 50 nuclear plants in Japan… This one had to endure a force enough to shift the island’s coast by more than 7 feet. And no direct structural failure. I’d say that’s still a pretty darn good accomplishment engineering wise. One oversight is thought to be the planning of location for the emergency pumps driven by the emergency diesel generators for the shutdown cooling supply. The emergency pumps may have been in a location that was swamped by the tsunami… Possibly poor planning, as a tsunami is likely to accompany an event powerful enough to trigger automatic shutdown of the plant due to vibration.
Highly possible. Big Japanese companies as a rule are driven by high levels of bureaucracy and oftentimes it takes a long time for a decision to be made. And until that time little information is released. In the power (and nuclear industry), Japan does not have a great track record of reporting “incidents” right away either. (Unfortunately) I can say this based on actual experience.
With a light water reactor, loss of coolant will of course result in temperature rise (which is why the explosion occurred in the first place). I’m no expert on nukes, but I don’t think the reaction can continue. I think one of the dangers is if/by how much the reactor was breached, and what are the true impacts of the radiation in what was released.
Let’s pray for the people of Japan and those that were affected.