No. 43: 20:00, April 5
NHK news regarding status of Fukushima Daiichi nuclear power station yesterday and today.
●High level of cesium detected in sand lances
Small fish caught in waters off the coast of Ibaraki have been found to contain radioactive cesium above the legal limit. Ibaraki is south of Fukushima prefecture, where the crippled Fukushima Daiichi nuclear power plant is located. Ibaraki Prefecture says 526 becquerels of radioactive cesium was detected in one kilogram of sand lances. The acceptable limit is 500 becquerels. It is the first time that higher-than-permitted levels of radioactive cesium have been found in fish. All local fishery cooperatives in the prefecture have agreed to suspend sand lance fishing at the request of the prefectural government.
Tuesday, April 05, 2011 18:58 +0900 (JST)
●TEPCO starts injecting agent to stop leakage
The operator of the crisis-hit Fukushima nuclear plant has injected a hardening agent beneath a leaking concrete pit in a bid to stem the flow of highly radioactive water into the sea. Tokyo Electric Power Company started infusing liquid glass into gravel below the pit near the Number 2 reactor at 3 PM on Tuesday. TEPCO spotted a crack in the pit 3 days ago while trying to find the source of the leakage of contaminated water into the Pacific Ocean. Since then, the utility has tried in vein to seal the pit with concrete, or to plug piping leading into it with a polymer mixture. A test using a dye agent showed the possibility that the radioactive water is leaking from a cracked pipe, and then seeping through gravel into the concrete pit. TEPCO is planning to board up the breached sections of an offshore dike to prevent the tainted water from spreading further into the sea. It is also considering building underwater silt barriers at 3 locations, including one near a water intake for the Number 2 reactor.
Tuesday, April 05, 2011 18:57 +0900 (JST)
●Review of Japan's nuclear policy suspended
The government has decided to suspend discussions on revising Japan's nuclear policy until the crisis at the Fukushima Daiichi power plant is over. The Cabinet Office's Atomic Energy Commission met on Tuesday for the first time since the March 11th earthquake and tsunami crippled the plant. The commission said it is taking the accident at the nuclear plant under the gravest consideration and that it has shaken the country's basic confidence in atomic power generation. Last year in December the commission launched discussions for revising the national outline on the use of nuclear energy. The current outline was formed in 2005. It covers basic policies on the use, research, development and promotion of nuclear power. The commission says it will decide its next step depending on developments at Fukushima and how the national debate on Japan's energy policy evolves. The commission chief, Shunsuke Kondo, said there is no denying that there are defects in Japan's nuclear safety standards. He added that the commission's existence itself could be questioned in the future and ruled out any new moves by the regulatory body until the Fukushima crisis is resolved. Kondo suggested that the accident at the plant will have a major impact on the government's policy on the use of nuclear power in Japan.
Tuesday, April 05, 2011 16:52 +0900 (JST)
●S Korea criticizes release of radioactive water
South Korea has expressed concern over Japan's release of contaminated water into the sea from the troubled Fukushima Daiichi nuclear power plant. The Japanese government approved the action by the plant operator. Tokyo Electric Power Company began dumping wastewater containing radioactive materials, including iodine-131 with a level of about 100 times the legal limit, into the sea to stabilize the crippled plant on Monday. South Korea's Foreign Affairs and Trade Ministry conveyed its concern to Japan's Foreign Ministry on Monday evening through its embassy in Tokyo. The South Korean ministry pointed out that release of contaminated wastewater could be a violation of international law. South Koreas have been increasingly worried about radioactive contamination of tap water and farm products. Minute amounts of radioactive material have been detected in the country after the trouble of the nuclear plant. There's growing criticism in the country that Japan failed to notify neighboring countries in advance about the release of contaminated water.
Tuesday, April 05, 2011 16:02 +0900 (JST)
●7.5 mil. times legal limit of iodine in sea
The operator of the stricken Fukushima Daiichi nuclear power plant says 7.5 million times the legal limit of radioactive iodine 131 has been detected from samples of seawater near the plant. Tokyo Electric Power Company, or TEPCO, found on Saturday that contaminated water was leaking from a cracked concrete pit near the No. 2 reactor.
Experts say this makes it clear that highly radioactive substances from the reactor are flowing into the sea, and that the leak must be stopped as soon as possible. The utility firm said samples of water taken near the water intake of the No. 2 reactor at 11:50 AM Saturday contained 300,000 becquerels of iodine 131 per cubic centimeter, or 7.5 million times the legal limit. TEPCO said the figure had dropped to 200,000 becquerels per cubic centimeter, or 5 million times the legal limit, in samples taken at 9:00 AM Monday. Monday's sample also contained 1.1 million times the legal limit of cesium 137, which has a half life of 30 years. On March 27th, 13-million becquerels of iodine 131 per cubic centimeter of water were detected in the turbine building of the No. 2 reactor. On Wednesday, water was found accumulated in a tunnel near the turbine building and the radiation level on the surface was measured at more than 1,000 millisieverts per hour. The Nuclear and Industrial Safety Agency says it believes the radioactive substances are from nuclear fuel which leaked from the reactor into the water and flowed out.
Tuesday, April 05, 2011 15:10 +0900 (JST)
●Discharge of radioactive water into sea continues
Tokyo Electric Power Company, or TEPCO, is continuing its operation to discharge wastewater containing low-level radioactive substances into the sea from the troubled Fukushima Daiichi nuclear power plant. The work began Monday evening in a bid to make room for more highly radioactive water from the No.2 reactor. In order to prevent more contaminated water from leaking into the sea, the government has approved the operation as an emergency measure under a law regulating nuclear reactors
. The power company says it plans to use 10 pumps to release a total of 10,000 tons of wastewater, and that by 9:00 AM Tuesday 2,800 tons had been discharged. TEPCO also started disposing 1,500 tons of low-level contaminated water near the No.5 and No.6 reactors at 9:00 PM on Monday. It discharged 30 tons by midnight, and the operation resumed at 6:00 AM on Tuesday. The utility firm says the concentration of radioactive substances in the water being released is up to 500 times the legal limit. But it says even if people were to eat fish caught in nearby waters every day for one year, their radiation exposure would be 0.6 millisieverts, which is below the annual permissible level of one millisievert. Chief Cabinet Secretary Yukio Edano told reporters on Tuesday that even though this was done to prevent highly contaminated water from flowing into the sea, he is very sorry that they must intentionally discharge the wastewater. He added the government will properly monitor developments and take all possible measures to prevent the contaminated water from spreading into the open ocean.
Tuesday, April 05, 2011 12:11 +0900 (JST)
●TEPCO struggling to halt radioactive leaks
The operator of the disaster-stricken Fukushima Daiichi nuclear power plant is struggling to halt the flow of highly radioactive water into the Pacific Ocean.
The Tokyo Electric Power Company, known as TEPCO, found last Saturday that contaminated water was pouring out from a cracked concrete pit near the No.2 reactor. The company has tried in vain over the past 3 days to seal the pit with concrete, or to plug the leak with water-absorbing polymers. TEPCO now suspects that the radioactive water could be leaking from a cracked pipe, and then seeping through gravel into the damaged concrete pit. It is planning to inject a type of chemical into the gravel to harden it so that water won't flow through. TEPCO is also planning to board up the breached sections of an offshore dike to prevent the leaking water from spreading further in the sea. It is also considering putting up underwater silt barriers at 3 locations, including one near a water intake for the No.2 reactor. On another front, work continues in an urgent bid to remove highly contaminated water from reactor turbine buildings. The buildup of water is severely delaying efforts to restore the reactors' cooling functions. TEPCO is now working to empty turbine condensers at the No.1, 2 and 3 units, to make room to store and isolate the highly-concentrated radioactive water.
Tuesday, April 05, 2011 12:11 +0900 (JST)
●Edano: Gov't will closely monitor seawater
Chief Cabinet Secretary Yukio Edano says the government will closely monitor the sea where wastewater with low-level radioactive substances is being discharged. Edano spoke to reporters on Tuesday morning about the operation by Tokyo Electric Power Company to release contaminated wastewater from the troubled Fukushima Daiichi nuclear power plant. He said steps are in place to strengthen monitoring systems of the sea water. He added authorities are considering the best way to prevent the contamination from spreading, including the idea of putting up some kind of fence. On the impact on marine products, Edano said fishing has not resumed off the coast of Fukushima Prefecture, and will not for some time. He said fish off the coast of Ibaraki Prefecture will be monitored to see if the fishing of products that have been confirmed safe can resume. Edano also said in order to prevent unfounded rumors the government will confirm the safety of marine products by monitoring many types of produce over a wide area. The government spokesman said proper analyses will be made before shipment regulations are put in place
Tuesday, April 05, 2011 12:11 +0900 (JST)
●Japan briefs IAEA on nuclear plant accident
Japan has reported the latest details of the troubled Fukushima Daiichi nuclear power plant in northern Japan in a special seminar at the UN atomic energy agency. On Monday, the Japanese government held the joint seminar with the International Atomic Energy Agency on the sidelines of the IAEA's 10-day safety review meeting from Monday at its headquarters in Vienna.
Officials of Japan's Nuclear and Industrial Safety Agency and Science Ministry provided details about steps taken so far to cool reactors at the plant and radiation data to about 400 nuclear power policy specialists. Some attendees proposed the use of robots in areas under high radiation and asked how long it will take to clean up radioactive substances. Others suggested that lessons learned from Fukushima be used to improve the safety of nuclear reactors in IAEA member countries. Japanese officials say they will handle the crisis with help from experts throughout the world, and promised to thoroughly investigate the cause of the accident.
Tuesday, April 05, 2011 11:21 +0900 (JST)
●TEPCO continues battle to halt radioactive leakage
Tokyo Electric Power Company says it will try a new method to stop radioactive water leaking into the sea from its damaged Fukushima Daiichi nuclear power plant. TEPCO discovered on Saturday that contaminated water was gushing from a crack in a concrete pit near reactor Number 2. After unsuccessful attempts to plug the leak with concrete and absorbent polymers, the company now believes the water may be seeping out through cracks in a cable trench leading to the pit. TEPCO plans to pour a chemical agent through a hole in the ground to solidify the gravel around the trench. It says the work will begin Tuesday. In an effort to contain as much contamination as possible, TEPCO is also considering setting up undersea silt barriers near the reactor's seawater intake ducts and two other locations.
Tuesday, April 05, 2011 06:35 +0900 (JST)
●High radiation outside indoor advisory zone
Radiation measurements have exceeded levels at which people are advised to stay indoors in a town outside the 30-kilometer radius of the damaged Fukushima Daiichi nuclear plant. The science ministry continues to monitor radiation levels in areas where residents have not been advised by the government to evacuate or stay indoors. The monitoring detected 10.3 millisieverts of radiation at one location in Namie Town, some 30 kilometers northwest of the plant. The amount is calculated on the assumption that a person has remained outdoors for 11 consecutive days through Sunday. The finding is higher than the 10 millisieverts the government views as the criteria for remaining indoors. The Nuclear and Industrial Safety Agency says that as the radiation level was only detected in a limited area, it has no intention of expanding the indoor advisory zone at present. A nuclear expert has pointed out that the government should explain the details of the finding to the residents.
Monday, April 04, 2011 21:21 +0900 (JST)
●Seawater's radiation levels remain high
The operator of the damaged Fukushima Daiichi nuclear plant says radiation levels in seawaters near the plant are falling but remain high
. Tokyo Electric Power Company says the level of radioactive iodine-131 found 330 meters south of a water outlet of the plant's No. 1 to No 4 reactors was 4,385 times the legal limit on Wednesday last week. The level has since been declining. Iodine-131 measured in the same area on Sunday was 630 times the limit. The radioactive material measured 30 meters north of the outlet of the No. 5 and No. 6 reactors was 240 times the national limit, compared with 3,000 times the limit recorded last Friday. In a related story, the health ministry says 4,080 bequerels of radioactive iodine was detected in one kilogram of sand lances, a kind of fish, caught in waters off Ibaraki Prefecture, south of the troubled plant. The ministry says this level of iodine does not pose health risks, but that it will establish provisional national standards for iodine in fish as soon as possible.
Monday, April 04, 2011 21:03 +0900 (JST)
●Radioactive water continues to leak
Radioactive water continued to flow into the ocean at the damaged Fukushima Daiichi nuclear plant on Monday, and its source remains unknown. Plant operator Tokyo Electric Power Company discovered on Saturday that the contaminated water appeared to be gushing from a crack in a concrete pit near reactor Number 2. TEPCO first tried to pour concrete into the crack to halt the leak, but the attempt failed. On Sunday, the company injected a mixture of absorbent polymers, sawdust and newspaper to try and clog the flow, but this has yet to absorb the water. On Monday, workers tried to see if they could trace the pathway of the leak by dumping into the system a powder dye designed to turn water a milky white. The colorant was poured into a tunnel leading to the pit, but no white water has appeared so far. TEPCO now thinks the radioactive water may be coming from another source and is considering different strategies to find out where. If efforts to plug the leak continue to fail, the company will next try to set up undersea silt barriers near the reactor's seawater intake ducts to prevent radioactive water from spreading in the ocean. The barriers would have fiber curtains attached with weights that would extend to the sea bottom and contain the contaminated water.
Monday, April 04, 2011 18:57 +0900 (JST)