Monday, March 21, 2011

Japan Struggles To Deal With Nuclear Emergencies As Death Toll Climbs

The Japanese government continues to struggle to deal with the massive death and devastation following the 9.0 quake and tsunami swamped much of the northeastern portion of the country and disabled and badly damaged the nuclear reactors at Fukushima's nuclear power complex.

The death toll is now over 8,800 and expected to climb much higher in coming days. Hundreds of thousands are still homeless and many more have been evacuated from the exclusion zone around Fukushima because of the radiation hazard posed by the damaged reactors and storage pools.

A number of workers were forced to evacuate from reactor #3 because of smoke rising from the stricken reactor. Power crews from TEPCO have run new power lines to the four stricken reactors in the hopes of restoring coolant systems, but damage to some systems at one of the reactors has delayed efforts, and the smoke rising from #3 has led to still more delays. Delays were also likely because insufficient power is being delivered to the damaged reactors.

The US NRC has reported that they consider the situation at Fukushima to be stabilizing, which is a bit of good news in a sea of trouble.
Radiation containment domes at Japan’s Fukushima Dai-Ichi nuclear reactors are intact and the situation at the plant “is on the verge of stabilizing,” a U.S. Nuclear Regulatory Commission official said.

“Containment at units 1, 2 and 3 appear to be functional,” Bill Borchardt, executive director for operations at the agency, said today during a meeting at the agency’s headquarters in Rockville, Maryland.

Spent-fuel pools used to keep fuel rods from overheating at units 3 and 4 are stabilizing. Japanese Prime Minister Naoto Kan said progress was being made in restoring power to reactors No. 1 and No. 2, while Tokyo Electric Power Co. said it had connected No. 3 and No 4.

“The fact that offsite power is close to being available for use at plant equipment is perhaps the first optimistic sign that things could be turning around,” Borchardt said.
The damage to the reactors and the spent fuel pools is going to cause a redesign and reassessment of how spent fuel is stored. The design of the TEPCO reactors and spent fuel pools is no longer used, and there were tradeoffs in where and how the spent fuel rods were stored. The massive quake and resulting tsunamis highlighted the tradeoffs and the vulnerability of the spent fuel pools, which will likely lead to work to bolster the containment at spent fuel pools around the world to prevent the kinds of problems seen at Fukushima to minimize the possibility that a radiation release could occur as a result of failures to the coolant systems and backup systems.

More than a week after the quake and tsunami, new footage of the tsunami crashing ashore is being posted online along with some startling tales of survival:

The second video shows the sea walls handling the surging ocean for the initial bursts, but at the 8:00 mark or so, the waves simply overtop the sea wall, and the water rushes in. Those sea walls gave a measure of protection and time for people to get away from the coast as the tsunami came ashore. Those precious minutes cannot be overlooking in how Japan prepared for the tsunami and earthquakes - the death toll would have been surely much higher had those sea walls not been in place and the water rushed inland with those first surges.

The NY Times has a good graphic showing the status of the nuclear reactors at Fukushima, along with their storage pool situations. Meanwhile, TEPCO admits that it missed certain key inspections just weeks before the devastating quake and tsunami. A March 2 response from Japan's nuclear regulator says that it did not believe there was an immediate risk to safety as a result of the missed inspections. Those items that were not inspected included backup systems on one of the crippled reactors.


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