How the NRC Brass Refuses to Recognize Costly Lessons of Fukushima - truthout

[PamW]

2. Lessons already Learned.

The USA already learned the lessons of Fukushima, and we didn't need to have an accident to do it; just a little forethought.

Lesson 1: Don't build a nuclear power plant at sea-level in a tsunami-prone area.
The USA knows that already. For example, Diablo Canyon in California is built on an 85 foot bluff overlooking the Pacific. That bluff is over twice as high as the tsunami wave that flooded Fukushima. The Fukushima wave wouldn't have touched Diablo Canyon. San Onofre is at sea-level, but the fault system there won't make big tsunamis. California has side-slipping lateral faults, whereas Japan has vertical thrust faults.

Lesson 2: Don't build the diesel generator fuel tank above ground.
The Fukushima diesel generator fuel tank was above ground at dockside, for ease of refueling. In the USA, the NRC requires that the diesel generator fuel tanks be buried like at your local gas station.

Lesson 3: Don't put the backup diesel generator and switchgear in an unsealed basement. In the USA, the NRC requires that diesel generators be in watertight vaults if they are in danger of ground flooding, or be up high in the reactor building. When I was a graduate student at MIT, we toured Boston Edison's Pilgrim Nuclear Power Plant, which is a GE BWR with Mark I containment like Fukushima. While following our guide on one of the upper stories of the reactor building we came across the two big diesel engines. After looking over the engines, we rode a nearby elevator about 2 stories up, and we were at the top of the reactor building. So I can say from personal experience, that the Pilgrim diesels aren't anywhere they can get flooded out.

Lesson 4: Have offsite backup diesels ready to fly in and drill on the process.
The NRC requires reactor operators to have more backup diesel generators offsite and ready to fly in, in case of emergency. The operations personnel are required to drill on this. They are required to actually fly in the offsite diesel and hook it up to the plant. TEPCO attempted to fly in diesel generators; but when the generators got there, the connectors on the generators were incompatible with the connectors on the plant. If TEPCO had drilled, they would have found out first time that their backup offsite diesel generators didn't have the correct connectors.

Lesson 5: Japanese BWR Mark I containment buildings didn't have hardened vents to prevent build-up of hydrogen. One of the problems the NRC identified with the Mark I containment back in the '70s was that they didn't have adequate venting to prevent hydrogen gas build-up. The NRC mandated that all Mark I containment buildings must have a "hardened" vent.

The list goes on and on and on. But you get the idea. The NRC and US designers already thought about and solved the problems that the Japanese operators and regulators skipped over. Fukushima was the result.

The US nuclear power industry and regulators really have nothing to learn from the Fukushima accident; they knew it all, already.

PamW