Tuesday, March 15, 2011

Nuclear Emergency At Fukushima Gets Worse as Death Toll Climbs

How to help.

The death toll continues rising in Japan and is all but likely to grow over 10,000 (current official death toll is about 2,500 and 15,000 are unaccounted for) while the economic toll is likely to be over $100 billion (and the Japanese markets are taking a beating).

The situation at the Japanese nuclear reactors at Fukushima remains uncertain but is worsening (now rating a 6 out of 7 on the nuclear emergency scale) and the TEPCO and Japanese government is dealing with multiple emergencies at the facility - reactors that have lost coolant, a fire at storage pool facility for spent fuel rods, and explosions at the buildings housing reactors and their containment vessels.

The fire at the storage pool appears to be the most serious situation - and it is the one that has released significant amounts of radiation. There are concerns that the pool might be boiling and temperature control was lost. That's only the latest in a series of problems resulting from the 9.0 quake and subsequent tsunamis that destroyed backup systems, causing multiple failures, and power troubles for the country.

Radiation levels have risen and levels triggered alarms on the USS George Washington, which was in Yokohama. The US carriers USS George Washington and USS Ronald Reagan (which is currently conducting relief operations off the coast of Japan) are equipped to deal with nuclear emergencies - they are nuclear powered after all, and they've got nuclear engineers and experts on board to deal with potential radiation problems.

The rest of the Japanese people? Not so much, and the radiation exposures are extremely troublesome - and the problems seem to be overwhelming TEPCO and the government's ability to deal with them. So, while levels have dropped back down for the moment, the government is calling on Japanese to remain indoors to minimize potential exposures.

There are too many problems happening at once - dividing attention of those who need to get the situation under control. And just when you think one situation is calming down, a problem at the reactor next door takes your breath away - leaks, explosions, fires, etc.

Yet, even before all the facts are in, Germany is shutting down all its pre-1980 reactors, in what appears to be a political decision as the Germans don't exactly have a way to make up the generating capacity lost by shuttering those reactors.

What is clear is that backup systems will need to be reevaluated - how to deal with emergency situations such as now facing the Japanese. The backup coolant systems in place rely on pumps, but newer backup systems rely on gravity so that a loss of power would not disable the coolant systems. The situation may also lead to a reevaluation of how multiple reactors are sited at a given plant - such that a problem at one plant could lead to cascading failures at adjacent facilities particularly during a nuclear emergency - or that siting multiple reactors at a quake/tsunami prone area should not be done in the future because it could lead to too many power plants being thrown offline in a disaster event - disrupting the power grid.

Japan has requested assistance from the IAEA.

The ongoing release of radiation has meant that the classification of the nuclear emergency has been raised to a level 6 (Chernobyl being a 7).
The 1979 accident at Three Mile Island in Pennsylvania rates five on an international scale of zero to seven, while Chernobyl is put at seven, the highest.

Level 3 indicates a "serious incident" according to the International Atomic Energy Agency (IAEA) scale, while level four means there has been an "accident with local consequences". Level 6 is a "serious accident".

The 1986 explosion at the Soviet nuclear power plant in Chernobyl - rated a maximum 7 - was the world's worst nuclear disaster, with death toll estimates ranging from 4,000 to tens or even hundreds of thousands.

Mr Lacoste also said the concrete vessel around reactor No.2 at the plant, designed to contain radioactive debris, was "no longer sealed".

The confinement vessel, made out of reinforced concrete, surrounds the steel vessel that houses the nuclear reactor. It is designed to contain radioactive gas or dust, preventing them from being expelled into the air.

The agency said two "successive explosions, at 6:10am and 10:00am local time probably caused damage to the confinement vessel which is the source of the significant increase in detected radioactive releases".
If the containment vessel at Reactor 2 is no longer sealed, radiation will continue escaping until such time that the Japanese can figure out how to seal the reactor. That means likely encasing it in concrete much as the Soviets did with a sarcophagus around the ruined Chernobyl reactor and using sea water and boric acid to stop the nuclear chain reactions that give off tremendous heat even when the reactors are shut down; it was the failure of backup coolant systems that precipitated the failures and subsequent leaks and explosions. In the meantime, they have to deal with ongoing emergencies at adjacent reactors.

Updating status on the Fukushima reactors (as of about about 1PM ET):

Fukushima Daiichi Plant

Reactor No. 1: Cooling failure, partial melting of core, vapor vented, hydrogen explosion, seawater pumped in.

Reactor No. 2: Cooling failure, seawater pumped in, fuel rods fully exposed temporarily, vapor vented, damage to containment system, potential meltdown feared.

Reactor No. 3: Cooling failure, partial melting of core feared, vapor vented, seawater pumped in, hydrogen explosion, high-level radiation measured nearby.

Reactor No. 4: Under maintenance when quake struck, fire caused possibly by hydrogen explosion at pool holding spent fuel rods, pool water level feared receding.

Reactor No. 5: Under maintenance when quake struck, temperature slightly rising at spent fuel pool.

Reactor No. 6: Under maintenance when quake struck, temperature slightly rising at spent fuel pool.

Fukushima Daiini Plant

Reactor No. 1: Cooling failure, then cold shutdown.

Reactor No. 2: Cooling failure, then cold shutdown.

Reactor No. 3: Cold shutdown.

Reactor No. 4: Cooling failure, then cold shutdown.

Kyodo also reports that about two-thirds of Toshiba's 350 nuclear engineers, "are currently dealing with accidents at the Fukushima nuclear power plant."

Toshiba supplied much of the equipment for the reactors at the Fukushima No. 1, or Daiichi plant, Kyodo explains.

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