March 25, 2011
By DAVID JOLLY, HIROKO TABUCHI and KEITH BRADSHER
TOKYO — Japanese officials began encouraging people to evacuate a larger swath of territory around the Fukushima Daiichi nuclear plant on Friday as new signs emerged that parts of the crippled facility are so damaged and contaminated that it will be hard to bring the plant under control soon.
The authorities said that they would now assist people who want to leave the area from 12 to 19 miles outside the plant and that they were now encouraging “voluntary evacuation” from the area. Those people had been advised March 15 to remain indoors, while those within a 12-mile radius of the plant had been ordered to evacuate.
The United States has recommended that its citizens stay at least 50 miles away.
Speaking to a national audience at a news conference Friday night two weeks after the magnitude 9.0 earthquake and the devastating tsunami that followed it, Prime Minister Naoto Kan dodged a reporter’s question about whether the government was ordering a full evacuation, saying officials were simply following the recommendation of the Japan Nuclear Safety Commission.
“The situation still requires caution,” Mr. Kan, grave and tired-looking, told the nation. “Our measures are aimed at preventing the circumstances from getting worse.”
“The state of the plant is still quite precarious,” he said. “We’re working hard to make sure it doesn’t get worse. We have to ensure there’s no further deterioration.”
In the latest setback in the effort to contain the nuclear crisis evidence emerged that the reactor vessel of the No. 3 unit may have been damaged, an official said Friday. The development, described at a news conference by Hidehiko Nishiyama, deputy director-general of the Japan Nuclear and Industrial Safety Agency, raises the possibility that radiation from the mixed oxides or mox fuel in the reactor — a combination of uranium and plutonium — could be released.
One sign that a breach may have occurred in the reactor vessel, Mr. Nishiyama said, took place on Thursday when workers who were trying to connect an electrical cable to a pump in a turbine building next to the reactor were injured when they stepped into water that was found to be significantly more radioactive than normal.
Two workers were burned when water poured over the top of their boots and down around their feet and ankles, Linda Gunter, a spokeswoman for the Tokyo Electric Power Company, said. She said workers on an earlier shift had no problem with low boots, but the water rose between shifts and the injured workers were unprepared for the deeper water. A third worker was wearing higher boots and did not suffer the same exposure.
Like the injured workers, many of those risking their lives are subcontractors of Tokyo Electric, paid a small daily wage for hours of work in dangerous conditions. In some cases they are poorly equipped and trained for their task.
A Japanese physicist, who asked not to be identified so as not to damage his relations with the establishment, said it was “ridiculous” that the workers had not been wearing full protective gear.
The National Institute of Radiological Sciences said that 3.9 million becquerels per square centimeter of radiation had been detected in the water that the three workers stepped in — 10,000 times the level normally seen in coolant water at the plant.
The injured workers’ dosimeters suggested exposure to 170 millisieverts of radiation. But the institute said that the actual amount of radiation the workers are thought to have been exposed to in the water is 2 to 6 sievert. Even 2 sievert is eight times the 250 millisievert annual exposure limit set for workers at Daiichi.
Concerns about Reactor No. 3 have surfaced before. Japanese officials said nine days ago that the reactor vessel may have been damaged.
A senior nuclear executive who insisted on anonymity but has broad contacts in Japan said that there was a long vertical crack running down the side of the reactor vessel itself. The crack runs down below the water level in the reactor and has been leaking fluids and gases, he said.
The severity of the radiation burns to the injured workers are consistent with contamination by water that had been in contact with damaged fuel rods, the executive said.
“There is a definite, definite crack in the vessel — it’s up and down and it’s large,” he said. “The problem with cracks is they do not get smaller.”
The contamination of the water in the basement of the turbine building where the workers were injured — a separate building adjacent to the one that houses the reactor — poses a real challenge for efforts to bring crucial cooling pumps and other equipment back online.
“They can’t even figure out how to get that out, it’s so hot” in terms of radioactivity, he said. A big worry about reactor No. 3 is the mox fuel. The nuclear industry has no experience with mox leaks, and it is possible that unusual patterns in the dispersal of radioactivity from the plant partly result from the mox, he said.
But Michael Friedlander, a former nuclear power plant operator in the United States, said that the presence of radioactive cobalt and molybdenum in water samples taken from the basement of the turbine building raised the possibility of a very different leak.
Both materials typically occur not because of fission but because of routine corrosion in a reactor and its associated piping over the course of many years of use, he said.
The aggressive use of saltwater to cool the reactor and its storage pool for spent fuel may mean that more of these highly radioactive corrosion materials will be dislodged and contaminate the area in the days to come, posing further hazards to repair workers, Mr. Friedlander added.
The news Friday and the discovery this week of a radioactive isotope in the water supplies of Tokyo and neighboring prefectures has punctured the mood of optimism with which the week began, leaving a sense that the battle to fix the damaged plant will be a long one.
No one is being ordered to evacuate the second zone around the plant, officials said, and people may choose to remain, but many have already left of their own accord, tiring of the anxiety and tedium of remaining cooped up as the nuclear crisis simmers just a few miles away. Many are said to be virtual prisoners with no access to shopping and immobilized by a lack of gasoline.
“What we’ve been finding is that in that area life has become quite difficult,” Noriyuki Shikata, deputy cabinet secretary for Mr. Kan said in a telephone interview. “People don’t want to go into the zone to make deliveries.”
Mr. Shikata said the question of where those who chose to leave would go was still under consideration. The effort to move people comes at a time when there are already hundreds of thousands of Japanese displaced by the quake and tsunami.
Officials continue to be dogged by suspicions that they are not telling the entire story about the radiation leaks. Shunichi Tanaka, former acting chairman of the country’s Atomic Energy Commission, told The Japan Times in an interview published Friday that the government was being irresponsible in forcing people from their homes around the damaged plant without explaining the risks they were facing.
“The government has not yet said in concrete terms why evacuation is necessary to the people who have evacuated,” he said.
The National Police Agency said Friday that the official death toll from the March 11 earthquake and tsunami had passed 10,000, with nearly 17,500 others listed as missing.
There was some good news. Levels of the radioactive isotope found in Tokyo’s water supply fell Friday for a second day, officials said, dropping to 51 becquerels per liter, well below the country’s stringent maximum for infants.
On Wednesday Tokyo area stores were cleaned out of bottled water after the authorities said the isotope, iodine 131, had been detected in the city’s water supply and cautioned those in the affected areas not to give infants tap water. On Thursday cities in two of Tokyo’s neighboring prefectures, Chiba and Saitama, also reported disturbing levels of radiation in their water.
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Meanwhile, the senior nuclear executive who said the reactor vessel was definitely cracked also said Friday evening that the reason the United States Navy had moved nuclear-powered vessels like the Ronald Reagan aircraft carrier far from the plant was that officers had become concerned that radiation could enter the ships’ duct systems.
The worry is not that the radiation would pose a threat to the vessels’ crews but that even trace contamination of the ducts could create problems for years in the extremely sensitive equipment that is designed to detect any hint of a radioactive leak from onboard systems, said the executive, who insisted on anonymity to protect business connections.
The Navy initially sent the Ronald Reagan toward northeast Japan to help with earthquake and tsunami relief a week and a half ago but quickly pulled it back after Navy helicopter crews had low-level radiation exposure while flying near the power plant. The Navy has been sending vessels since then to the west coast of Japan, upwind of the reactors, and providing assistance from there, although this means considerably longer flight times to affected areas.
David Jolly and Hiroko Tabuchi reported from Tokyo and Keith Bradsher from Hong Kong. Takeshi Takizawa contributed reporting from Tokyo.
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