facility:reactor no

#Fukushima disaster could have been avoided, nuclear plant operator admits | Environment | guardian.co.uk
http://www.guardian.co.uk/environment/2012/oct/15/fukushima-disaster-avoided-nuclear-plant

The company at the centre of Japan’s worst nuclear crisis has acknowledged for the first time that it could have avoided the disaster that crippled the Fukushima Daiichi power plant last year.

In a reversal of its insistence that nothing could have protected the plant against the earthquake and tsunami that killed almost 20,000 people on 11 March, Tokyo Electric Power (Tepco) said it had known safety improvements were needed before the disaster, but had failed to implement them.

In a rare moment of introspection, an internal taskforce set up to reform the embattled utility said the firm feared that improvements in safety would highlight the risks to nuclear power plants and encourage the anti-nuclear lobby.

“There was a worry that if the company were to implement a severe-accident response plan, it would spur anxiety throughout the country and in the communities near where nuclear plants are sited, and lend momentum to the anti-nuclear movement,” the report said.

Nous y voilà, c’est la faute aux anti-nucléaire !

#nucléaire

Gerd Ludwig’s ’Long Shadow of Chernobyl’ project
http://www.boston.com/bigpicture/2012/02/gerd_ludwigs_long_shadow_of_ch.html

Internationally-renowned photojournalist Gerd Ludwig has spent years documenting the aftermath of the Chernobyl nuclear disaster.

http://inapcache.boston.com/universal/site_graphics/blogs/bigpicture/gerd_ludwig_chernobyl/bp1.jpg

On April 26, 1986, operators in this control room of reactor No. 4 at the Chernobyl Nuclear Power Plant committed a fatal series of errors during a safety test, triggering a reactor meltdown that resulted in the world’s largest nuclear accident to date. Today, the control room sits abandoned and deadly radioactive. Chernobyl Nuclear Power Plant, Ukraine, 2005 (Gerd Ludwig/INSTITUTE)

Core of reactor 1 melted 16 hours after quake | The Japan Times Online
http://search.japantimes.co.jp/cgi-bin/nn20110516a1.html

Monday, May 16, 2011

Core of reactor 1 melted 16 hours after quake
New analysis shows damage to fuel rods was surprisingly quick
Kyodo

The meltdown at reactor No. 1 in Fukushima happened more quickly than feared, Tokyo Electric Power Co. said Sunday in a new analysis.

The core of the heavily damaged reactor at the Fukushima No. 1 power plant is believed to have melted 16 hours after the March 11 mega-quake and tsunami rocked the complex in northeastern Japan.

Preliminary analysis shows that No. 1 had already entered a critical state by 6:50 a.m. on March 12, with most of its fuel having melted and fallen to the bottom of the pressure vessel, the plant operator said. Tepco released data Thursday showing some of the fuel rods had melted.

The reactor automatically halted operations immediately after the 2:46 p.m. quake, but the water level in the reactor dropped and the temperature began rising at around 6 p.m. The damage to the fuel rods had begun by 7:30 p.m., with most of them having melted by 6:50 a.m. the following day, the utility said.

While the utility had planned to bring the nation’s worst nuclear accident under control in around six to nine months from mid-April, it now has no choice but to abandon a plan to flood the containment vessel of reactor 1 because holes have been created by the melted fuel, an adviser to Prime Minister Naoto Kan said earlier Sunday.

Nevertheless, Goshi Hosono, the top official tasked with handling the nuclear crisis, told TV programs the government had yet to revise the timetable for bringing the crisis to an end.

Asked about initial plans to completely submerge the 4-meter-tall fuel rods by entombing the vessel in water, Hosono said, “We should not cause the (radioactive) water to flow into the sea by taking such a measure.”

Hosono said the government will instead consider ways to decontaminate the water being used to cool the fuel so that it can be recirculated instead of letting it flood the facility.

Hosono made the remarks after Tepco discovered a pool of water more than 4 meters deep and exceeding 3,000 tons in the basement of reactor No. 1. This suggests that the water, which is likely highly radioactive, is seeping through the holes after being injected into the reactor core.

From there, it is probably leaking from either the containment vessel or the suppression pool, which enclose the pressure vessel, and into the piping.

In a related revelation concerning a major mixup after the six-reactor complex lost power, Tepco and other sources said the same day that the utility had assembled 69 power supply vehicles at the plant by March 12 but that these proved virtually useless.

The inability to use the vehicles delayed the damage control work at the plant, significantly worsening the emergency.

Tepco earlier said it had tried to connect the vehicles to power-receiving equipment needed to operate the water pumps intended to cool down the reactors. But this failed because the equipment was submerged in seawater from the tsunami, which posed the risk that the equipment would short out.

Tepco’s account conflicts with the one detailed by the Nuclear and Industrial Safety Agency, which mentioned the first arrival of such a vehicle on the evening of March 11 but stopped mentioning it the following day, as the focus of attention had shifted to the need to release radioactive steam to relieve pressure that had built up inside the containment vessel of reactor 1.

The different versions of the story given by Tepco and the agency might come to a head as investigations progress to determine why efforts to immediately contain the crisis failed.