Radiation Errors Erode Confidence in Power Company
By ANDREW POLLACK and KEN BELSON
Published: April 5, 2011
TOKYO — The alarming figures pour forth daily about radiation emanating from Japan’s crippled nuclear power plant. But don’t believe everything you hear.
In at least a few embarrassing instances the numbers released by the owner of the plant, the Tokyo Electric Power Company, have been wrong, raising unnecessary alarm and eroding confidence in the company, whose reputation has already been battered and whose stock price fell to an all-time low on Tuesday.
In the latest incident the government’s nuclear regulatory body reprimanded Tokyo Electric after the company reported finding a rare radioactive isotope, tellurium 129, in a puddle in a turbine room at the plant only to say later that the finding was “doubtful.”
Tokyo Electric said late Monday that it had taken the reprimand seriously and that it would now vet certain data with outside experts before releasing it to the public, even if that meant delaying dissemination of some information.
The tellurium mistake followed one on March 27 when the company reported high levels at the Fukushima Daiichi plant of iodine 134, a rare isotope that disintegrates so quickly that it would not be present in large amounts unless nuclear fission had restarted. That raised the alarming prospect that the reactor might have been out of control. The company later said the initial report had been wrong.
And on March 31 the company said the groundwater near the plant was contaminated with 10,000 times the normal level of radiation, only to then question its own finding.
In all three cases, the mistaken measurements made the situation seem worse than it really was. That suggests that Tokyo Electric did not intend to use the data to cover up problems, but the retractions added to the questions already being raised about the company’s competence and credibility.
To be sure, the acknowledged errors represent only a tiny fraction of the samples being analyzed each day since the Fukushima plant was badly damaged by a huge earthquake and tsunami on March 11.
While Tokyo Electric analyzes some of its samples, others are sent to the Japan Atomic Energy Agency, an organization financed by the government. A spokesman for that agency said its results were not found to be in error.
The company uses a standard technique called gamma ray spectroscopy, which involves examining the energy levels of the gamma rays, a form of radiation, to determine types of isotopes and their levels.
“Someone who knows what they are doing could be off by 5 or 15 percent and someone who doesn’t know what they are doing can be off by orders of magnitude,” said Sheldon Landsberger, a professor of nuclear radiation engineering at the University of Texas and co-author of the book “Measurement and Detection of Radiation.”
Dr. Landsberger said it was hard to judge what was happening in Japan. “Working in the field environment is difficult,” he said.
Despite Tokyo Electric’s releases of data, some Japanese say the company, also known as Tepco, is not disclosing enough about the extent of the crisis.
“I don’t believe what the top people of Tepco say,” Yukiko Kimura, a 68-year-old housewife who volunteered at an evacuation center.
Other Japanese are so frustrated with the blizzard of statistics and lack of explanations that say they have stopped listing to briefings by Tokyo Electric and the government.
“We get all the numbers and units of radiation in the newspaper and on television, but I don’t know concretely what the effect is,” Kana Ohtani, 35, a cooking teacher said, speaking in the Tsukishima neighborhood of Tokyo. “I rather want to know the effects on our body than the meaning of the numbers and units.”
Shares of Tokyo Electric fell 18 percent Tuesday on the Tokyo Stock Exchange to about $4.30, the lowest level in its 60 years as a publicly traded company, with investors concerned that the company could face tens of billions of dollars in claims for damages.
Concern was raised when the company announced Monday that it would dump more than 11,000 tons of radioactive water into the Pacific Ocean. On Tuesday, Hidehiko Nishiyama, deputy director general of the Nuclear and Industry Safety Agency, said that Japan notified other countries shortly before the operation began.
Even before the dumping, radiation in the water near the Fukushima plant greatly exceeded acceptable levels, with sampling on Monday finding iodine 131 at five million times the acceptable level at one location.
That is believed to stem from a leak into the ocean from a concrete pit at the plant.
In at least a few embarrassing instances the numbers released by the owner of the plant, the Tokyo Electric Power Company, have been wrong, raising unnecessary alarm and eroding confidence in the company, whose reputation has already been battered and whose stock price fell to an all-time low on Tuesday.
In the latest incident the government’s nuclear regulatory body reprimanded Tokyo Electric after the company reported finding a rare radioactive isotope, tellurium 129, in a puddle in a turbine room at the plant only to say later that the finding was “doubtful.”
Tokyo Electric said late Monday that it had taken the reprimand seriously and that it would now vet certain data with outside experts before releasing it to the public, even if that meant delaying dissemination of some information.
The tellurium mistake followed one on March 27 when the company reported high levels at the Fukushima Daiichi plant of iodine 134, a rare isotope that disintegrates so quickly that it would not be present in large amounts unless nuclear fission had restarted. That raised the alarming prospect that the reactor might have been out of control. The company later said the initial report had been wrong.
And on March 31 the company said the groundwater near the plant was contaminated with 10,000 times the normal level of radiation, only to then question its own finding.
In all three cases, the mistaken measurements made the situation seem worse than it really was. That suggests that Tokyo Electric did not intend to use the data to cover up problems, but the retractions added to the questions already being raised about the company’s competence and credibility.
To be sure, the acknowledged errors represent only a tiny fraction of the samples being analyzed each day since the Fukushima plant was badly damaged by a huge earthquake and tsunami on March 11.
While Tokyo Electric analyzes some of its samples, others are sent to the Japan Atomic Energy Agency, an organization financed by the government. A spokesman for that agency said its results were not found to be in error.
The company uses a standard technique called gamma ray spectroscopy, which involves examining the energy levels of the gamma rays, a form of radiation, to determine types of isotopes and their levels.
“Someone who knows what they are doing could be off by 5 or 15 percent and someone who doesn’t know what they are doing can be off by orders of magnitude,” said Sheldon Landsberger, a professor of nuclear radiation engineering at the University of Texas and co-author of the book “Measurement and Detection of Radiation.”
Dr. Landsberger said it was hard to judge what was happening in Japan. “Working in the field environment is difficult,” he said.
Despite Tokyo Electric’s releases of data, some Japanese say the company, also known as Tepco, is not disclosing enough about the extent of the crisis.
“I don’t believe what the top people of Tepco say,” Yukiko Kimura, a 68-year-old housewife who volunteered at an evacuation center.
Other Japanese are so frustrated with the blizzard of statistics and lack of explanations that say they have stopped listing to briefings by Tokyo Electric and the government.
“We get all the numbers and units of radiation in the newspaper and on television, but I don’t know concretely what the effect is,” Kana Ohtani, 35, a cooking teacher said, speaking in the Tsukishima neighborhood of Tokyo. “I rather want to know the effects on our body than the meaning of the numbers and units.”
Shares of Tokyo Electric fell 18 percent Tuesday on the Tokyo Stock Exchange to about $4.30, the lowest level in its 60 years as a publicly traded company, with investors concerned that the company could face tens of billions of dollars in claims for damages.
Concern was raised when the company announced Monday that it would dump more than 11,000 tons of radioactive water into the Pacific Ocean. On Tuesday, Hidehiko Nishiyama, deputy director general of the Nuclear and Industry Safety Agency, said that Japan notified other countries shortly before the operation began.
Even before the dumping, radiation in the water near the Fukushima plant greatly exceeded acceptable levels, with sampling on Monday finding iodine 131 at five million times the acceptable level at one location.
That is believed to stem from a leak into the ocean from a concrete pit at the plant.
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