TOKYO—Highly radioactive water continued to gush into the Pacific Ocean from Japan’s tsunami-crippled nuclear plant on Sunday despite efforts to stop the leak with a chemical substance mixed with sawdust and shredded newspaper.
The leak discovered on Saturday was the latest setback in the increasingly difficult bid to regain control of the six-reactor Fukushima Dai-ichi Nuclear Power Station, which has been spewing radiation since the March 11 earthquake and tsunami that have left 27,400 people dead.
Hidehiko Nishiyama, deputy director of the Nuclear and Industrial Safety Agency, said the polymer mix had not yet sealed the crack in a maintenance pit that was spewing water into the sea.
Engineers have not given up and say they should know by Monday whether the latest effort will work. Polymer can absorb enormous amounts of water and expands 50 times its original size.
An earlier attempt to seal the crack with concrete failed.
2 bodies found
Earlier on Sunday, the operator of the stricken nuclear plant said that two of its engineers who went missing since the day the earthquake and tsunami hit Japan last month had been confirmed dead.
Tokyo Electric Power Co. (TEPCO) said the two engineers—one 21 years old and the other 24—died on March 11 around 4 p.m., after the tsunami hit the Dai-ichi plant.
TEPCO said the two engineers had lost a lot of blood and went into shock. Their bodies were found on Wednesday in the basement of the turbine building connected to Reactor No. 4, but the company said it did not release the details of the deaths until the families were notified.
They are the first two workers at the Dai-ichi plant to die in the aftermath of the March 11 quake, tsunami and subsequent nuclear crisis.
“It pains me that these two young workers were trying to protect the power plant while being hit by the earthquake and tsunami,” TEPCO chair Tsunehisa Katsumata said in a statement.
Five other workers who worked for subsidiary companies have died at other TEPCO facilities. Three workers at the Dai-ichi plant have been injured by stepping into pools of contaminated water inside one reactor building.
Leak at Reactor No. 2
The confirmation of the deaths came a day after Japanese safety officials announced that highly radioactive water was leaking directly into the sea from a maintenance pit near the crippled Reactor No. 2.
This was the first time the source of any leaks was found, and it was a fresh reminder of the dangerous side effects of the strategy to cool the reactors and spent fuel storage pools by pumping hundreds of tons of water a day into them.
Japanese officials have said they have little choice at the moment since the normal cooling systems at the Dai-ichi plant are inoperable and more radioactive material would be released if the reactors were allowed to melt down fully or if the rods caught fire.
The feed-and-bleed strategy was adopted after the cooling systems failed and the reactors overheated to dangerous levels when the massive tsunami knocked out power to the Dai-ichi plant three weeks ago.
Endless problems, however, have led to substantial amounts of radiation leaking into the atmosphere, ground and sea in the world’s worst nuclear crisis since the 1986 meltdown at Chernobyl in the former Soviet Union.
Workers racing to drain the excess water have struggled to figure out how to store it. On Saturday, some contaminated water was transferred to a barge to free up space in tanks on land. A second barge has also arrived.
A worker who fell into the ocean on Friday while trying to board a barge carrying water to cool the plant did not show any immediate signs of being exposed to unsafe levels of radiation, officials said on Saturday, but they were waiting for test results to be sure.
More water, more problems
“The more water they add, the more problems they are generating,” said Satoshi Sato, a consultant to the nuclear energy industry and a former engineer with General Electric. “It’s just a matter of time before the leaks into the ocean grow.”
Tetsuo Iguchi, a quantum engineering professor at Nagoya University, said that the leak discovered on Saturday raised fears that contaminated water might be seeping out through many more undiscovered sources.
Unless workers could quickly stop the leaking, Iguchi said TEPCO officials could be forced to reevaluate the so-called feed-and-bleed strategy, in which they flood the reactors and fuel ponds with water and then release the steam that the hot fuel rods generate.
“It is crucial to keep cooling the fuel rods, but on the other hand, these leaks are dangerous,” he said. “They can’t let the plant keep leaking high amounts of radiation for much longer.”
Workers discovered a crack about several centimeters wide in the small maintenance pit, which lies between Reactor No. 2 and the sea.
The space directly above the water leaking into the sea had a radiation reading of more than 1,000 millisieverts per hour, a level dangerous to humans.
Tests of the water within the pit later showed the presence of 1 million becquerels per liter of iodine 131, a radioactive substance. That level of iodine is 10,000 times what is normal for water at the plant.
Long battle
No quick end is in sight for the world’s worst nuclear emergency since the 1986 Chernobyl disaster, warned a government lawmaker who advises Prime Minister Naoto Kan on the crisis at the Dai-ichi plant.
“This is going to be a long battle,” said Goshi Hosono, who highlighted the threat from 4.5-meter-long spent fuel rods that remain volatile for months and need to be cooled in pools with circulating water.
“The biggest challenge at this plant is that there are more than 10,000 spent fuel rods,” Hosono said.
“It will take a very long time to reprocess them, and we sincerely apologize for that. It is unacceptable that radioactive substances keep being released, causing anxiety among the people. Probably it will take several months before we reach the point” where all radiation leaks stop, he added.
Protest
Outside the TEPCO headquarters in Tokyo, about 100 protesters shouted: “No more nuclear plants!” and “TEPCO, government—be responsible!”
“This accident has burdened the socially weak, the farmers and fishermen,” said Mitsue Matsuda, 47, a resident from the tsunami-hit Iwate prefecture who said she had friends living near the Fukushima plant.
“The land will stay contaminated for decades or more,” she said.
The health ministry said its latest tests of regional vegetables, fruit and marine products had found radioactive cesium and iodine in some crops but still within the limits set by law.
Authorities have stressed there is no immediate public health threat from seafood because fishing within a 20-kilometer radius is banned, arguing that ocean currents will quickly dilute the contaminants.
Overshadowed
The nuclear crisis has overshadowed recovery efforts since the 9-magnitude earthquake and 15-meter-high tsunami devastated Japan’s northeast region.
Along the tsunami-ravaged coast, 25,000 members of Japanese and US military and rescue crew entered the third and final day of a massive search for bodies.
While cherry blossoms have opened in Tokyo, temperatures plunged again, leaving tens of thousands of homeless shuddering in evacuation camps along the ravaged northeast coast of Japan’s main Honshu Island. Reports from Associated Press, New York Times News Service and Reuters