[After the levels were correctly measured, airborne radioactivity in the unit 2 turbine building still remained so high — 1,000 millisieverts per hour — that a worker there would reach his yearly occupational exposure limit in 15 minutes. A dose of 4,000 to 5,000 millisieverts absorbed fairly rapidly will eventually kill about half of those exposed.]
By Chico
Leaked water sampled from one unit Sunday had 100,000 times the radioactivity of normal background levels, although the Tokyo Electric Power Co., which operates the plant, first calculated an even higher, erroneous, figure it didn’t correct for hours.
After the levels were correctly measured, airborne radioactivity in the unit 2 turbine building still remained so high — 1,000 millisieverts per hour — that a worker there would reach his yearly occupational exposure limit in 15 minutes. A dose of 4,000 to 5,000 millisieverts absorbed fairly rapidly will eventually kill about half of those exposed.
The latest confusion in the operation to stave off a full-scale nuclear meltdown at the crippled facility underscores the immense challenges for the several hundred workers in a desperate battle to restart the critical cooling systems. Seventeen workers have been exposed to high levels of radiation, including three who were hospitalized last week, as technicians conducted highly nuanced electrical work in dark conditions that one nuclear industry expert termed “hellish.”
Japanese authorities say efforts to control Fukushima Japan
On Monday morning, Japan
Police stationed in the area have noticed more people returning to gather belongings and “there is a risk” of returning home now, Edamo said. Many families fled quickly after the earthquake and tsunami struck more than two weeks ago with only the clothes they were wearing.
Evidence of rising contamination in and around the plant has tempered optimism from a week ago, when engineers began work to restore power to the first of the damaged reactor buildings. Japan
The dangers in unit 2 merely add to the growing challenges. Radioactive water is pooling in four of Fukushima
While a Tepco spokesman said Sunday that he did not know how the radioactive water was leaking from the reactor cores, Yukio Edano, chief cabinet secretary, said in a televised interview Sunday morning that the reactor itself had not been breached.
He said it was clear that water that could have been inside the unit 3 reactor had leaked but the reactor had not been breached. Still, he said, “Unfortunately, it seems there is no question that water, which could have been inside the reactor, is leaking.’’
Unlike in newer reactor designs, the older boiling-water reactors at Daiichi are pierced by dozens of holes in the bottoms of their reactor vessels. Each hole allows one control rod — made of a neutron-absorbing material that quickly stops nuclear fission inside the reactor — to slide into the reactor from below, as happened when the earthquake shook the plant March 11. During normal operations, a graphite stopper covers each hole, sealing in highly radioactive primary cooling water, said Arnie Gundersen, a consultant at Fairewinds Associates with 40 years of experience overseeing boiling-water reactors.
But at temperatures above 350 degrees Fahrenheit, the graphite stoppers begin to melt.
“Since it is likely that rubble from the broken fuel rods . . . is collecting at the bottom of the reactor, the seals are being damaged by high temperature or high radiation,” Gundersen said. As the graphite seals fail, water in the reactor will leak into a network of pipes in the containment buildings surrounding each reactor — the very buildings that have been heavily damaged by explosions. Gundersen said that this piping is probably compromised, leaving highly radioactive water to seep from the reactor vessels into broken pipes — and from there into the turbine buildings and beyond.
To stabilize the facility, workers are trying to repair the elaborate cooling system, necessary to keep the reactor cores and spent fuel pools from overheating. For now, they are conducting this work in dark, steamy conditions. Nuclear safety experts say they must shift out of the most dangerous areas every 30 minutes to an hour, to prevent radiation overexposure.
Meanwhile, they are racing to repair motor pumps. Their environment resembles a cavern of cables. Some of the equipment was damaged during the March 11 earthquake and tsunami. Other equipment has been corroded by salt water, which was poured into the facility during earlier efforts to cool the reactors.
“To a layman, you’d be scared to death,” said Lake Barrett Three Mile Island . “You’re working with salt water around your feet. This is not the way electricians usually work.”
The number of workers at the Daiichi plant fluctuates from day to day, ranging between 500 and 1,000. But Tepco employees account for only a part of the labor force. Last Tuesday, for instance, there were 700 people at the plant, a nuclear agency official said. The figure included 500 Tepco employees, 100 subcontracted workers, and 100 members of Japan
One subcontracted worker who laid cables for new electrical lines March 19 described chaotic conditions and lax supervision that made him nervous. Masataka Hishida said neither he nor any of the workers around him was given a dosimeter, a device used to measure one’s exposure to radiation. He was surprised that workers were not given special shoes; rather, they were told to put plastic bags over their street shoes. When he was trying on the gas mask for the first time, he said, the supervisor told him and other subcontractors, “Listen carefully, I’m only going to say this one time,” while explaining how to use it.
When Hishida finished his work shift, an official scanned his whole body for radiation. He came up clean, except for the very tip of his beard. He was sent into a shower where he lathered up and scrubbed his beard. He was tested again and passed.
A few days later, still worried about the extent of his radiation exposure, he trimmed his beard.
IN CHINA
[The power of microblogging was dramatically illustrated last month by Peng Gaofeng, whose 3-year-old son was abducted in March 2008 in Shenzhen. Peng, 32, spent three years searching for the boy and was told by police to give up. But after a friend posted the boy’s picture on his microblog, Peng got a tip on Feb. 1 from Jiangsu
Microblogs — called “weibo” — seem to be one step ahead of China China
But weibo users are regularly engaged in a virtual debating free-for-all, touching on some of the most off-limits or politically touchy topics.
There are microblog comments on the uprisings in the Middle East — including questions on whether the popular unrest might spread to China Tibet
Still, posts involving the jailed dissident and Nobel Peace Prize winner Liu Xiaobo or the outlawed Falun Gong spiritual movement may be deleted or blocked from re-posting. “Weibo has become the public hall for people to discuss public affairs and formulate opinions,” said Hu Yong, associate professor of journalism at Peking University China
In democratic countries, “people have various channels to express their opinions, like through the media, the judicial system, in general elections and even through the petition process,” Hu said. “But in China
It isn’t that the authorities have suddenly discovered a new tolerance for free speech, Hu said. The weibo-using community is growing so fast, the 140-character posts go out so quickly and the technology is so new that they have been unable to keep up.
The government, meanwhile, is trying to stay ahead of the trend. Local Communist Party bosses, propaganda department officials, municipal police departments and the provincial party chief in Xinjiang have recently launched microblogs.
Chen Tong, executive vice president and editor in chief of Sina.com , China China Beijing
Still, the number of government officials with weibo accounts remains low. Singers, entertainers and athletes are the most popular microbloggers, attracting as many as 10 million fan-followers each.
With Twitter blocked in China
The power of microblogging was dramatically illustrated last month by Peng Gaofeng, whose 3-year-old son was abducted in March 2008 in Shenzhen. Peng, 32, spent three years searching for the boy and was told by police to give up. But after a friend posted the boy’s picture on his microblog, Peng got a tip on Feb. 1 from Jiangsu
About the same time, sociologist Yu Jianrong started a microblog called “Taking snapshots to rescue child beggars.” Yu asked followers to photograph beggars and post them to the account. By late February, his campaign had attracted 240,000 followers.
Police have solved some cases with the help of microblogs, and citizens have exposed instances of official corruption or foul play. Weibo has also been used to mobilize Chinese to donate money to people in need.
“In civil society, in community involvement, weibo is playing a role like no other organization can play,” said Xu Xiaoping, a businessman and avid microblogger with 1.5 million followers. “Weibo gives people power.”
But weibo’s power in shaping public opinion and its potential for social organizing have attracted the most attention. “Weibo is not only the place for people to express themselves, but also the place where people organize together,” Hu said.
Xie Gengyun, a professor at Shanghai Jiaotong University
“Weibo is changing the structure of the public opinions in China
richburgk@washpost.com
Researcher Zhang Jie contributed to this report.
