Published: March 25 2011 06:13 | Last updated: March 26 2011 13:01
Japan’s prime minister has warned there is still no end in sight to the world’s worst nuclear crisis in 25 years as his government sought to clear residents from the vicinity of the radiation-leaking Fukushima Daiichi atomic plant.
“The situation is still unpredictable and we are still working to prevent it worsening,” Naoto Kan, the prime minister, told a news conference on Friday. “We have to continue to work with extreme urgency to deal with each development.”
The government warned that the vessel housing the No 3 reactor may have suffered a breach, possibly exposing the reactor's fuel rods to the air.
Miroslav Lipar, of the International Atomic Energy Agency, said at a briefing in Vienna, said: “Most probably there is some small leak from the containment and that allows in atmospheric pressure.”
Fears about the escape of radioactive material from the plant were heightened on Saturday when the Nuclear and Industrial Safety Agency said that levels of iodine-131 in seawater near the plant were 1,251 times normal.
The tests were carried out on Friday morning about 300 meters from the southern water discharge outlet of Fukushima Daiichi.
NISA officials said that the radioactive discharge posed little threat to marine life because it would be diluted in the vast expanse of the Pacific Ocean. But it added to the evidence that the reactor containment is damaged enough for radioactivity to escape into the environment.
Two workers irradiated by contaminated water at the plant on Thursday were moved to a radiation treatment centre near Tokyo on Friday, authorities said.
In a prelude to a possible mandatory evacuation, the government issued a notice “recommending” that people still living between 20km and 30km from the quake-crippled plant should move further away.
It was the first time authorities had sought to clear more residents from districts around the Fukushima Daiichi plant since the first days of the nuclear crisis, which was triggered by an earthquake and tsunami on March 11. The US has recommended its nationals stay at least 80km from the plant.
The difficult battle to stabilise the plant’s overheating reactors is continuing, with Japan’s defence minister saying the US had lent military barges to deliver large quantities of fresh water to the plant, to replace the seawater currently being sprayed and pumped through fire hoses into its reactor buildings.
Experts are concerned that salt has accumulated as the seawater has evaporated, potentially corroding equipment inside the reactors and making it more difficult to cool their overheated uranium fuel.
The decision to step up evacuation efforts was described as a response to increasingly difficult living conditions inside the 20-30km band, where for nearly two weeks people have been under orders to stay inside.
Supplies of food and water inside the area have run short and it was becoming increasingly difficult to keep the area supplied from the outside, said Yukio Edano, chief cabinet secretary. Some civilian delivery workers have refused to enter the area, forcing the government to divert military and other emergency crews to take up the slack.
“Given that supplies are not getting in, it would be a good choice to move calmly to a more stable place,” Mr Edano said. “We cannot deny than an evacuation might be ordered in the future if radiation increases.”
A mandatory 20km evacuation zone has been in place since March 12, a day after the record magnitude-9 quake and 14-metre tsunami knocked out the power station’s electrical systems. Without power, cooling equipment shut down and uranium fuel overheated, expelling combustible gases and radiation.
Radiation doses exceeding legal limits have already been detected in food and water in areas outside the evacuation zone. Chinese customs authorities said they found two Japanese travellers arriving with radiation levels “seriously” over the limit, Reuters reported on Friday.
So far only emergency workers at the plant have absorbed radiation doses that most experts would consider dangerous, however.
The two technicians who have been moved to Tokyo were laying a cable in a seawater-flooded turbine building attached to the plant’s No 3 reactor, where radiation has been leaking from a damaged reactor core and a storage tank for spent nuclear fuel.
Radiation meters showed the workers had also absorbed airborne doses of more than 170 millisieverts, above the 100 mSv threshold at which researchers say cancer risk increases. A third worker who did not come into contact with contaminated water received a similar airborne dose. Several hundred technicians, firefighters and soldiers are fighting to contain the crisis, and have become national heroes due to the high stakes and dangerous conditions at the plant.
An official at the Nuclear and Industrial Safety Agency said the three technicians had continued working after radiation alarms sounded.
Nisa ordered Tokyo Electric Power, the plant’s operator, to tighten its procedures for protecting personnel. The three technicians work for an unidentified Tepco subsidiary or contractor.
The 100 mSv level is normally the legal limit for emergency workers at nuclear facilities, but Japan has raised its limit to 250 mSv to allow work at the plant to continue. Seventeen workers have so far absorbed radiation doses above 100 mSv, according to Tepco, while 14 have suffered non radiation-related injuries.
Technicians have fitted new external power lines to all the reactor units at the plant, whose back-up generators were knocked out by the tsunami. But the cooling systems have been damaged by the quake, explosions and seawater being used to cool the overheated fuel, and there is no guarantee they will still work.
Copyright The Financial Times Limited 2011. Print a single copy of this article for personal use. Contact us if you wish to print more to distribute to others.
“The situation is still unpredictable and we are still working to prevent it worsening,” Naoto Kan, the prime minister, told a news conference on Friday. “We have to continue to work with extreme urgency to deal with each development.”
The government warned that the vessel housing the No 3 reactor may have suffered a breach, possibly exposing the reactor's fuel rods to the air.
Miroslav Lipar, of the International Atomic Energy Agency, said at a briefing in Vienna, said: “Most probably there is some small leak from the containment and that allows in atmospheric pressure.”
Fears about the escape of radioactive material from the plant were heightened on Saturday when the Nuclear and Industrial Safety Agency said that levels of iodine-131 in seawater near the plant were 1,251 times normal.
The tests were carried out on Friday morning about 300 meters from the southern water discharge outlet of Fukushima Daiichi.
NISA officials said that the radioactive discharge posed little threat to marine life because it would be diluted in the vast expanse of the Pacific Ocean. But it added to the evidence that the reactor containment is damaged enough for radioactivity to escape into the environment.
Two workers irradiated by contaminated water at the plant on Thursday were moved to a radiation treatment centre near Tokyo on Friday, authorities said.
In a prelude to a possible mandatory evacuation, the government issued a notice “recommending” that people still living between 20km and 30km from the quake-crippled plant should move further away.
It was the first time authorities had sought to clear more residents from districts around the Fukushima Daiichi plant since the first days of the nuclear crisis, which was triggered by an earthquake and tsunami on March 11. The US has recommended its nationals stay at least 80km from the plant.
The difficult battle to stabilise the plant’s overheating reactors is continuing, with Japan’s defence minister saying the US had lent military barges to deliver large quantities of fresh water to the plant, to replace the seawater currently being sprayed and pumped through fire hoses into its reactor buildings.
Experts are concerned that salt has accumulated as the seawater has evaporated, potentially corroding equipment inside the reactors and making it more difficult to cool their overheated uranium fuel.
The decision to step up evacuation efforts was described as a response to increasingly difficult living conditions inside the 20-30km band, where for nearly two weeks people have been under orders to stay inside.
Supplies of food and water inside the area have run short and it was becoming increasingly difficult to keep the area supplied from the outside, said Yukio Edano, chief cabinet secretary. Some civilian delivery workers have refused to enter the area, forcing the government to divert military and other emergency crews to take up the slack.
“Given that supplies are not getting in, it would be a good choice to move calmly to a more stable place,” Mr Edano said. “We cannot deny than an evacuation might be ordered in the future if radiation increases.”
A mandatory 20km evacuation zone has been in place since March 12, a day after the record magnitude-9 quake and 14-metre tsunami knocked out the power station’s electrical systems. Without power, cooling equipment shut down and uranium fuel overheated, expelling combustible gases and radiation.
Radiation doses exceeding legal limits have already been detected in food and water in areas outside the evacuation zone. Chinese customs authorities said they found two Japanese travellers arriving with radiation levels “seriously” over the limit, Reuters reported on Friday.
So far only emergency workers at the plant have absorbed radiation doses that most experts would consider dangerous, however.
The two technicians who have been moved to Tokyo were laying a cable in a seawater-flooded turbine building attached to the plant’s No 3 reactor, where radiation has been leaking from a damaged reactor core and a storage tank for spent nuclear fuel.
Radiation meters showed the workers had also absorbed airborne doses of more than 170 millisieverts, above the 100 mSv threshold at which researchers say cancer risk increases. A third worker who did not come into contact with contaminated water received a similar airborne dose. Several hundred technicians, firefighters and soldiers are fighting to contain the crisis, and have become national heroes due to the high stakes and dangerous conditions at the plant.
An official at the Nuclear and Industrial Safety Agency said the three technicians had continued working after radiation alarms sounded.
Nisa ordered Tokyo Electric Power, the plant’s operator, to tighten its procedures for protecting personnel. The three technicians work for an unidentified Tepco subsidiary or contractor.
The 100 mSv level is normally the legal limit for emergency workers at nuclear facilities, but Japan has raised its limit to 250 mSv to allow work at the plant to continue. Seventeen workers have so far absorbed radiation doses above 100 mSv, according to Tepco, while 14 have suffered non radiation-related injuries.
Technicians have fitted new external power lines to all the reactor units at the plant, whose back-up generators were knocked out by the tsunami. But the cooling systems have been damaged by the quake, explosions and seawater being used to cool the overheated fuel, and there is no guarantee they will still work.
Copyright The Financial Times Limited 2011. Print a single copy of this article for personal use. Contact us if you wish to print more to distribute to others.
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