April 4 (Bloomberg) -- Tokyo Electric Power Co. began dumping radioactive water from its crippled Fukushima Dai-Ichi nuclear station into the sea to make room to store more toxic liquids that have hampered efforts to restart cooling systems.
The release of the water, which has low levels of radiation, will make space for more dangerous fluid in the basement of turbine buildings at the Nos. 2 and 3 reactors. The government approved the plan, the first deliberate toxic discharge into the ocean, the chief cabinet secretary said.
“We didn’t have any other alternatives,” Yukio Edano told reporters in Tokyo today. “This is a measure we had to take to secure safety.”
Workers at the utility, known as Tepco, have been battling to restart cooling pumps that were knocked out by a March 11 quake and tsunami, resulting in a partial meltdown of some of the plant’s six reactors. Tokyo Electric plans to release 11,500 tons of water containing radioactive iodine levels about 100 times the regulatory limit.
“Until they get rid of that water they can’t get in there to sort out the pumps,” Robin Grimes, a professor of materials physics at Imperial College in London, said by telephone. “If they’re going against regulatory guidelines, that’s definitely not something you’d want to do unless you had very little choice. It’s the least worst option.”
Deliberate Release
Tepco will discharge 10,000 tons of water from its waste treatment facility and another 1,500 tons accumulated in pits outside reactor Nos. 5 and 6, said Masateru Araki, a company spokesman.
Filtering radiation from the water would take too long and its release will help protect equipment in the buildings housing the reactors, Junichi Matsumoto, another Tepco spokesman, said today at a news conference streamed over the Internet.
Radioactive iodine in seawater near the plant was 630 times the regulatory limit, Tepco said today in a statement. The sample was taken 330 meters south of a water discharge outlet yesterday. The company released the information after being ordered by Japan’s Nuclear and Industrial Safety Agency to reevaluate radiation data following the publication of inaccurate figures.
Plugging a Crack
Tepco had been struggling to stop contaminated water from reactor No. 2 from leaking into the ocean through a conduit used to take in seawater.
The company first tried to plug a crack in a power-cable storage pit near the reactor by filling it with concrete on April 2, and yesterday attempted to clog it with a mix of sawdust, newspaper and absorbent polymer used in baby diapers.
The utility plans to build an undersea silt barrier to stop the leak of radioactive fluids and help contain toxic water within the conduit, Hidehiko Nishiyama, Japan’s spokesman on nuclear safety, said in Tokyo earlier today.
“A silt fence ensures that mud down deep doesn’t seep through,” Nishiyama said. The barrier may take “several days” to install.
A silt fence is usually used to filter dirt and solid impurities in rivers and seas during construction, said Yoshinori Hashimoto, a spokesman at Maeda Kosen Co., which makes industrial materials made from fiber, including the barriers. They are also used at the seawater intake gate of nuclear power plants, he said, adding that neither Tepco nor the government has approached the company to place an order.
Threat Not Severe
The leak itself may not pose a severe threat, said Kathryn Higley, professor of nuclear engineering and radiation health physics at Oregon State University.
“You’re likely to have a footprint in the soil and the sands and sediments as that material leaks out, but the impact is likely to be pretty minimal,” Higley said yesterday in a telephone interview. “Even if it does get out into that marine environment, that area around there has been pretty badly torn up, so there’s not a lot of life to be impacting.”
Tepco and government officials met Jeffrey Immelt, chief executive officer of General Electric Co., to discuss technical support to contain the crisis at the Fukushima reactors that are based on the U.S. company’s design.
Fairfield, Connecticut-based GE has offered technical assistance and help through its venture with Hitachi Ltd. Immelt met with Tepco officials including Chairman Tsunehisa Katsumata yesterday and Trade Minister Banri Kaieda today.
GE will offer gas turbines to ease energy shortages in the Tokyo region, Immelt told reporters after meeting Kaieda.
Bodies Discovered
The bodies of two workers missing since Japan’s strongest earthquake on record were found yesterday, Tepco said. They had been performing maintenance in the basement of the No. 4 reactor at the plant, the company said yesterday.
The latest deaths bring to seven the number of workers killed at the utility’s two nuclear power complexes in Fukushima, including five employees of sub-contractors whose deaths were confirmed on March 12 and 14.
The total number of dead and missing from the earthquake and tsunami was 27,653 as of 10 a.m. Tokyo time today.
It may take several months to stop the emission of radioactive material, Goshi Hosono, a lawmaker in the ruling Democratic Party of Japan, told reporters. Hosono is an envoy between the government and Tepco.
“The more contamination, the more difficult the recovery becomes, and the more trouble they have each day, the more workers are being exposed,” said John Price, a Melbourne-based consultant on industrial accidents and former member of the safety policy unit at the U.K.’s National Nuclear Corp. “It’s going to stabilize, but to get it cleaned up and made safe may take decades,” he said by telephone today.
A Tepco executive said yesterday he isn’t optimistic about the prospect of containing damage at the Fukushima’s No. 3 reactor.
“I don’t know if we can ever enter the No. 3 reactor building again,” Hikaru Kuroda, the company’s chief of nuclear facility management, said at a press conference.
--With assistance from David Wethe in Houston, James Paton in Sydney and Kari Lundgren and Stephen Cunningham in London. Editors: Alex Devine, Stephen CunninghamTo contact the reporters on this story: Ichiro Suzuki in Tokyo at isuzuki@bloomberg.net; Tsuyoshi Inajima in Tokyo at tinajima@bloomberg.net
To contact the editor responsible for this story: Amit Prakash at aprakash1@bloomberg.net
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