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| NYT: Daiichi shows 4 badly damaged reactors |
Today:{18.3.11}A diesel generator is running at the disaster site allowing authorities to run cooling systems for Units 5 and 6 where temperatures in the spent fuel pools are above normal. Both of these units were off line at the time of the earthquake for routine maintenance, and have not caused critical problems. The most severely damaged reactors, Units 1,2,3 and 4, are being cooled with water dumps from helicopters and high pressure water hoses from the ground. The media have referred to these heroic liquidators as "suicide squads" because they are working in extremely high levels of radiation emitted by the reactors. Unit 3 is a plutonium oxide fueled reactor (MOX) whose radioactive emissions are particularly dangerous. Inhaled radioactive plutonium lodges in the organs and bones where it continues to emit particles for a biological half life of 200 years. Plutonium has a metallic taste. Radiation levels dropped 20 points on Thursday and are still declining Friday. (3,600 µSv on Thursday or 4 times the safe exposure for a year). The immediate threat of multiple total meltdowns may have been averted, but it will be months before the reactors are stable enough to be approached for disposal and entombment operations. [video] Japan's government belatedly raised the nuclear incident level to 5 In the United States, New York Governor Cuomo has called for the shutdown of the Indian Point reactors, while Illinois Governor Quinn has ordered a safety review of the state's four GE Mark I reactors. GE shares have lost $12bn in value since Monday. Sorry, Mr. President, no nuclear reactor on Earth could withstand a 9.0 magnitude earthquake followed by a 30 foot tsunami wave without being damaged somehow.
Still more:{16.3.11}As often happens in disasters, authorities are in conflict over the exact conditions at the site. The US Nuclear Regulatory Commission chairman said in Washington the spent fuel rods in Unit #4 holding tank are uncovered. Both the NRC and the US Department of Energy have experts on the scene. US experts are recommending an expansion of the exclusion zone to fifty miles (80kms). Japanese utility officials deny the pool is empty of water and say "conditions are stable" at Unit #4. Workers are close to completing an emergency power line to the station which would allow constant pumping of water to cool the reactors on the verge of total meltdown. IAEA, the international body concerned with nuclear matters complains the information coming out of Japan is too slow and vague. Kyodo, the Japanese national news agency said 33% of Unit #2 and 70% of Unit #1 spent fuel rods are damaged and the cores of both reactors 1 and 2 partially melted. Radiation levels are now elevated across northern Japan.
Developments: TEPCo says workers have returned to the Daiichi site after a reduction in radiation levels. However, fears of large radiation releases are affecting the population which can recall previous fallout horrors in their history. The Emperor took the rare step of addressing the nation concerning his deep concern about the "unprecedented" disaster at the power station. The used fuel rod pool in Unit 4 [left of picture] atop the reactor constitutes the principle risk of direct fallout into the atmosphere. Unlike the active reactor core, the spent fuel assemblies are not shielded except for immersion in a tank of water to keep them cool. Previous ventings and explosions have released radioactive hydrogen gas and steam. Authorities are considering using a water canon to douse Unit 4 after "extremely strong" radiation prevented military helicopters approaching close from above with water to quench the reactor. Unit 2 primary containment (the concrete and steel structure surrounding the reactor vessel inside the reactor building sometimes referred to as secondary containment) is believed to be significantly breached according to the Nuclear Information and Resource Service, a nuclear activist website with sources in Japan. The catastrophe is certainly "un stress collective mondial".
Further: {15.3.11}A potential repeat of the Chernobyl meltdown looms ahead for Fukushima Prefecture, and the world braces for another release of radiation. A fire in the irradiated fuel pool at Unit 4 was reportedly extinguished, but a new fire has erupted Wednesday morning, local time. Radiation levels are too high to fight this fire says TEPCo. According to Le Monde, two eight meter wide breaches opened in the containment building of reactor unit #4. Tokyo Electric Power has evacuated all but 50 heroic "liquidators" from the stricken Daiichi nuclear power station. It is highly improbable that these few men can deal successfully with four overheating and melting reactors simultaneously. In an irony obscured by human tragedy, there is no power to run safety systems. TEPCo may be throwing up its hands after a week of refusing to face the grave reality of the nuclear crisis. Citizens living within 30kms of the plant have been ordered to stay indoors. Citizens within 20kms have been evacuated. NOAA computer projections indicate most of the radiation from the melting reactors will blow out over the Pacific. Residents of Tokyo metro are now experiencing low levels of radiation attributable to the nuclear disaster. The French nuclear safety authority is rating the Daiichi disaster a 6 on the scale of nuclear incidents. The USGS has upgraded the quake responsible for the devastation of northern Japan to 9 on the magnitude scale making it the fourth largest earthquake in recorded history. Several US nuclear reactors are located near the ocean in seismic regions such as theDiablo Canyon and San Onofre facilities. Both facilities are in densely populated Southern California. Are you paying attention Mr. Obama?
Latest:{14.3.11}A third explosion has rocked the crippled Fukusima-Daiichi nuclear power plant early Tuesday morning, local time. Officials admitted there is a containment breach of reactor #2 and it is leaking radiation. Radiation monitors spiked to 8,217µSv/hr before the explosion[1]. A damaged valve prevented utility workers releasing pressure in Unit 2, a condition which also prevented water being pumped into the containment to cool the reactor. Fuel rods in the core were exposed to the air for many hours making it highly likely structural integrity of the fuel assembly has been lost. TEPCo officials are still discounting the possibility of a total meltdown while apologizing professedly for "inconvenience" in typical Japanese fashion[2]. There are now three reactors at Fukusima-Daiichi that are teetering on the edge of uncontrolled fission taking place. An American physicist told the New York Times, "It's way past Three Mile Island already". Seventeen US sailors on an aircraft carrier offshore were discovered contaminated with radiation. The US Navy is moving ships farther away from the Fukushima area.
[1] a microSievert is equivalent to 0.1 millirems. The allowable US dose from all nuclear sources is 100 millirems per year. So the recorded spike at Fukushima is equivalent to 822 millirems/hr or about eight times the yearly permissible dose each hour! A full body dose over 3 Sv will cause death in 50% of cases within 30 days. More than two dozen Chernobyl workers died of overexposure to radiation. Some liquidators as they were called literally tied pieces of sheet lead to their bodies in a desperate effort to protect themselves.
[2] a Wikileaks cable shows that a young Diet member,Taro Kono, expressed concern to US embassy officials about Japan's nuclear energy industry. He said the bureaucracy and power companies were suppressing alternative energy development and withholding information from Diet members and the public. He questioned if there was any safe place to store nuclear waste in "the land of volcanoes".
More: {13.3.11}Reuters reports and Japanese officials confirm there has been a hydrogen gas explosion at Unit 3. The Monday morning blast was felt by AP reporters 30 miles away. It is not yet clear how much radioactivity has been released by the blast, but a wall of the reactor building collapsed and six people have been injured. Radioactive cesium and idodine has been detected outside the plant, an indicator of fuel rod melting. Seawater injection into Unit 3 probably caused the buildup of hydrogen gas resulting in the second explosion. Unit 3 containment was vented to the atmosphere on Sunday morning. Venting to relieve pressure is planned at another nearby nuclear plant, Fukushima Daini, where cooling also failed according to TEPCO in Units 1,2, and 3 [video] Nuclear power officials have been careful to understate the extent and effects of the unfolding nuclear disaster in Fukushima prefecture. TEPCO now admits that six to ten feet of Unit 3 reactor core was uncovered for a considerable period of time despite frantic efforts to pump seawater into the reactor. As previously reported below, TEPCO states in translation, "The fuel's integrity has been considerably compromised. We are assessing a considerably serious situation."
Update: As casualty figures mount into the thousands, Japan's nuclear engineers are preparing for yet another disaster within a disaster: meltdowns at several reactors at once. According to western experts, [video] the fuel assembly at Unit 1 of the Fukushima Plant has lost its "geometry" and is now a molten mass of extremely radioactive uranium. Unit 3 core is also partly melted. The Chief Cabinet Secretary has warned another hydrogen explosion could take place at Unit 3. Pumping of sea water into Unit 2 is being readied according to a Tokyo Electric Power Co. (TEPCO) spokesperson. The condition of reactors #4, 5, and 6[photo] has not been mentioned in reports. Tsunami waves overwhelmed back-up electric generators responsible for powering cooling pumps after the main generators stopped working. Engineers fitted mobile battery powered generators, but they were insufficiently powerful to properly cool the reactors. Reports are that fuel rods in Unit 1 were partially uncovered and at least three workers exposed to high levels of radiation got radiation sickness. An emergency was declared at nearby Onagawa Plant, but Japanese officials have told IAEA that its three reactor units are under control.
As a fuel assembly looses its geometry, or structure, it becomes more unstable because the fission reaction is unmediated. Flooding the reactor with sea water and boron will cool a critical core, but that action also presents its own problems as the chemistry involved becomes more complex and could even restart nuclear chain reactions. Radiological exposure of workers and civilians will become increasingly likely, as the crippled reactors are periodically vented of radioactive steam. Unit 3 runs on MOX or mixed oxides, unlike Unit 1, an older reactor that is fueled with enriched uranium. MOX when released to the atmosphere is more toxic because the fuel is plutonium based. 180,000 people living within 12 miles around the plant have been ordered to evacuate. On Sunday, radiological levels at the plant exceeded the permissible level of 500 µSv/hr. It appears that Japanese officials are preparing for the worse case scenario, a complete meltdown of two reactors. On the international scale of nuclear and radiological events, Japanese officials are currently rating the situation a "4" out of 7. Three Mile Island in 1979 is a 5 and Chernobyl in 1986 is rated a 7.
{12.3.11}Beyond the unfavorable cost issues associated with nuclear power is the ever present one of safety. There is the unsettled problem of how to permanently dispose of high level nuclear waste. But the devastation wrought on Japan brings the susceptibility of nuclear power facilities to natural disasters to the forefront. Chernobyl showed that containment of a nuclear furnace is paramount to its safe operation. Japan has fifty-four operating nuclear plants. Five nuclear reactors at two facilities in Japan have been damaged in the historic quake, the fifth largest in recorded times. Yesterday, the government announced that it would vent hydrogen gas from one reactor in order to relieve internal pressure, a sign complex cooling plumbing had failed. Today an explosion at the Fukushima Dai-ichi plant [video] destroyed a reactor building and proved engineers had failed to solve the pressure problem. Apparently the stainless steel reactor vessel is still intact, but there is no indication from officials of its state of integrity. The reactor is a General Electric Mark I design (BWR) that has been criticized for its "pressure suppression design" rather than a more robust design intended to withstand high pressures in an accident. Twenty-three US plants use a GE Mark I design.
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| Reality: 10m wave destroys |