The current situation at Japan’s Fukushima nuclear plant remains serious and unstable. Graham Andrew, Special Adviser to the IAEA Director General on Scientific and Technical Affairs, said that while there continues to be some improvements, the overall situation at the nuclear station is still “very serious”.

Another negative development in the world’s worst nuclear crisis in a quarter of a century is that the temperature at the spent fuel pools at Reactor No. 1 has reached 400 degrees celsius. This was at 380-390 degrees a few hours back.

From Reuters:

    Hidehiko Nishiyama, the deputy-director general of Japan’s nuclear safety agency, later said the smoke at reactor No.3 had stopped and there was only a small amount at No.2.

    He gave no more details, but a TEPCO executive vice president, Sakae Muto, said the core of reactor No.1 was now a worry with its temperature at 380-390 Celsius (715-735 Fahrenheit).

    “We need to strive to bring that down a bit,” Muto told a news conference, adding that the reactor was built to run at a temperature of 302 C (575 F).

    Asked if the situation at the problem reactors was getting worse, he said: “We need more time. It’s too early to say that they are sufficiently stable.”

Also from Yomiuri online:

経済産業省原子力安全・保安院は２３日午前の記者会見で、東京電力福島第一原 発１号機で同日までに、原子炉内の温度が４００度以上あることがわかったことを明らかにした。

（2011年3月23日11時25分 読売新聞）

Google Translated:

Nuclear and Industrial Safety Agency Ministry of Economy, Trade and Industry at a press conference Friday morning, the day before the No. 1 nuclear power plant in Fukushima Daiichi TEPCO announced that it was found that the temperature of 400 degrees in a nuclear reactor.

(25 min at 11 Yomiuri Shimbun, March 23, 2011)

WallStreet Pit

Tokyo Electric Power Co. said Wednesday it has observed a neutron beam, a kind of radioactive ray, 13 times on the premises of the Fukushima Daiichi nuclear plant after it was crippled by the massive March 11 quake-tsunami disaster.

TEPCO, the operator of the nuclear plant, said the neutron beam measured about 1.5 kilometers southwest of the plant's No. 1 and 2 reactors over three days from March 13 and is equivalent to 0.01 to 0.02 microsieverts per hour and that this is not a dangerous level.

The utility firm said it will measure uranium and plutonium, which could emit a neutron beam, as well.

In the 1999 criticality accident at a nuclear fuel processing plant run by JCO Co. in Tokaimura, Ibaraki Prefecture, uranium broke apart continually in nuclear fission, causing a massive amount of neutron beams.

In the latest case at the Fukushima Daiichi nuclear plant, such a criticality accident has yet to happen.

But the measured neutron beam may be evidence that uranium and plutonium leaked from the plant's nuclear reactors and spent nuclear fuels have discharged a small amount of neutron beams through nuclear fission.

Kyodo News

Austrian scientists have released what appears to be the first clear, independent data concerning radiation levels in the immediate aftermath of the Fukushima radiation leak.

By releasing data from two monitoring stations of the Comprehensive Test Ban Treaty Organization (CTBTO) from Japan and California, researchers from the Central Institute for Meteorology and Geodynamics in Vienna have calculated backwards to estimate the true levels of radiation from Fukushima.

"The estimated source terms for iodine-131 are very constant, namely 1.3 x 10^17 becquerels per day for the first two days (US station) and 1.2 x 10^17 becquerels per day for the third day (Japan)," the institute said in a German-language statement posted on Wednesday on its website.

"For cesium-137 measurements, (the US station) measured 5 x 10^15 becquerels, close, while Japan had much more cesium in its air. On this day, we estimate a source term of about 4 x 10^16."

A "becquerel" is the unit that measures how many radioactive nuclei decay per second, and the "source term" refers to the quantity and type of radioactive material released into an environment.

"The nuclear catastrophe at Chernobyl had a source term of iodine-131 at 1.76 x 10^18 becquerels of cesium-137 at 8.5 x 10^16 bequerels," the statement added. "The estimated for Fukushima source terms are thus at 20 percent of Chernobyl for iodine, and 20-60 percent of Chernobyl for cesium."

In the same statement, the Austrian institute also noted that a CTBTO station in Iceland had detected very small amounts of iodine-131 as of March 20, which does pose a health risk.

'Likely in the same order of magnitude' as Chernobyl

Source: DW World

Now they're telling us...

March 24, 2011
Iodine levels on the rise near Fukushima plant
updated at 13:29 UTC, Mar. 24

Tokyo Electric Power Company says the level of radioactive iodine is on the rise in waters near the crippled nuclear power plant in Fukushima Prefecture.

On Wednesday morning, the plant operator detected radioactive iodine-131 at a level 147 times higher than safety standards at a location 330 meters away from a water outlet of the facility.

The substance measured 127 times above the standard on Monday, when the first survey was conducted. The reading dropped the following day to 30 times over the benchmark.

Wednesday's survey also found higher-than-standard doses of radioactive cesium-134 and cesium-137.

The government's Nuclear and Industrial Safety Agency says levels of radioactive materials fluctuate depending on ocean currents, adding it will continue to closely monitor the situation.

Thursday, March 24, 2011 15:34 +0900 (JST)

March 24, 2011
Latest situation update from: hisz.rsoe.hu...

Situation Update No. 58
On 24.03.2011 at 04:17 GMT+2

The Fukushima nuclear power plant was rocked with new tremors on Wednesday, leading to more tension for engineers who have been working nonstop since the 9.0 magnitude earthquake and tsunami hit the country on March 11, causing the plant’s reactors to lose essential cooling mechanisms.

Workers have diffused the situation somewhat in recent days by pumping seawater into the reactors, preventing what was close to becoming a serious nuclear disaster. The new quakes hitting the plant reached magnitudes of 6.0, but officials immediately downplayed fears of additional damage at Fukushima. Even though black smoke was seen coming out of the plant’s third reactor, the government claims the situation is not serious.

Workers at the plant have restored power to essential lighting that will allow engineers to assess damaged equipment in the hopes of getting the plant's cooling systems back online. Once the cooling systems are functioning, workers can stop pumping seawater into the plant. The reactors will not be usable to generate nuclear energy and electricity because of the application of seawater, but damage to spent-fuel tanks and the reactors themselves need to be assessed and repaired to control radiation.

Restoring essential systems could take days, warned international organizations. The seawater, while averting a nuclear disaster, could have caused corrosion and salt build-up that may slow down the process of getting the systems back online quickly. 

2 workers exposed to high radiation at Fukushima plant hospitalized

TOKYO, March 24, Kyodo

Two of three workers who were laying cable at the troubled Fukushima Daiichi nuclear plant on Thursday were exposed to high-level radiation and were hospitalized due to injuries to their feet, the nuclear safety agency and the plant operator said.

The three male workers were exposed to radiation amounting to 173 to 180 millisievert at around 12:10 p.m. while laying cable underground at the No. 3 reactor's turbine building. The two workers of plant operator Tokyo Electric Power Co.'s affiliated firm had their feet under water while carrying out the work, according to the Nuclear and Industrial Safety Agency.

The two, who were diagnosed as having sustained beta ray burn injuries at a Fukushima hospital, will later be sent to the National Institute of Radiological Sciences in Chiba Prefecture, the agency said.

TEPCO said radioactive water may have seeped through their radiation protective gear. The injuries are caused by direct exposure to beta rays, the utility added.

The level is lower than the maximum limit of 250 millisievert per year set by the health ministry for workers tackling the ongoing emergency at the Fukushima plant.

So far, one worker who was injured following a hydrogen explosion at the No. 3 reactor on March 14 was found to have been exposed to radiation amounting to over 150 millisievert.

Kyodo News

The government is reviewing whether to continue its current directive for people living 20 to 30 kilometers away from a troubled nuclear plant in Fukushima Prefecture to remain indoors, with an eye on possibly recommending they relocate further away to make their everyday life easier over the long term, the top government spokesman indicated Thursday.

Chief Cabinet Secretary Yukio Edano noted in a news conference that reconsidering the directive does not mean the risk of radiation leaks from the plant is increasing.

''We are reviewing whether people can continue living under the current conditions,'' Edano said.

People within the 20 to 30 km range have been inconvenienced by increasingly limited goods available for living such as gasoline and foods, as trucking companies are shunning the government-designated area.

Edano noted that people in the area have been getting supplies from the Self-Defense Force troops.

After the catastrophic March 11 earthquake and tsunami crippled the Fukushima Daiichi nuclear plant and caused radiation leaks, directives were issued for people living in a 20-kilometer radius of the plant to evacuate and those in the 20-30 km range to stay indoors.

Edano emphasized that a revised order of this kind must be dealt with cautiously so as not to create a misperception that danger from the radiation leaks is spreading.

Kyodo News

March 24, 2011 10:22 a.m. EDT
More U.S. states find traces of radiation from Japan
By Elizabeth Landau, CNN

(CNN) -- Colorado and Oregon have joined several other Western states in reporting trace amounts of radioactive particles that have likely drifted about 5,000 miles from a quake and tsunami-damaged nuclear power plant in Japan, officials say.

But, on a portion of its website dedicated to tracking such radiation, the Environmental Protection Agency noted Wednesday that these and other readings "show typical fluctuation in background radiation levels" and -- thus far -- "are far below levels of concern."

Sampling from a monitor in Colorado -- part of a national network of stations on the lookout for radioactivity -- detected miniscule amounts of iodine-131, a radioactive form of iodine, the state's public health and environmental department said Wednesday in a press release.

On the same day in Portland, Oregon, tiny quantities of iodine-131 were also detected by an Environmental Protection Agency air monitor, Oregon public health officials said.
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Small amounts of radioactive material were detected Wednesday, too, in Hawaii -- just as they had a day earlier, according to the EPA. But while they were above the historical and background norm, the levels weren't considered harmful to human health.

Washington and California previously reported low levels of radioactive isotopes that likely came from Japan's Fukushima Daiichi nuclear power plant, which has been releasing radioactive particles into the air since its cooling and other systems were damaged by a 9.0-magnitude earthquake and massive tsunami on March 11. Efforts continued Thursday to cool down the spent nuclear fuel rods, prevent a further meltdown of the plant's six reactor cores and curb the release of additional radioactive material.

Sampling of these radioactive particles from these various monitors will be further analyzed at the EPA's national lab.

Still, right now, U.S. health officials have emphasized that, at about 5,000 miles from the plant, the West Coast is unlikely to see any dangerous levels of radiation regardless of what happens in Japan. Radioactive particles disperse in the air, thus there is less of a hazard the farther away you are.

"Our finding is consistent with findings in Washington and California. We have expected to find trace amounts of the isotopes released from the Japanese plant. There is no health risk," Gail Shibley, administrator of Oregon's Office of Environmental Public Health, Oregon Public Health Division, said in a statement.

Besides the Hawaii readings, the Environmental Protection Agency has found trace amounts of radioactive iodine, cesium and tellurium at four RadNet air monitor filters on the West Coast -- three in California and one in Washington. These levels are consistent with what a U.S. Department of Energy monitor found last week, the EPA said Monday.

Americans typically get exposure to radiation from natural sources such as the sun, bricks and rocks that are about 100,000 times higher than what has been detected in the United States.

There is no need for anyone as a precautionary measure to take potassium iodide, a medication that can counter the harmful effects of iodine-131, health officials say.

Three workers were exposed to high-level radiation Thursday while laying cable at the troubled Fukushima Daiichi nuclear plant, and two of them were taken to hospital due to possible radiation burns to their feet, the nuclear safety agency and the plant operator said.

The three men in their 20s and 30s were exposed to radiation amounting to 173 to 180 millisieverts at around 12:10 p.m. while laying cable underground at the No. 3 reactor's turbine building.

The two hospitalized are workers of plant operator Tokyo Electric Power Co.'s affiliated firm and had their feet under water while carrying out the work from 10 a.m., according to the utility known as TEPCO and the Nuclear and Industrial Safety Agency.

The two, who were diagnosed with possible beta ray burns at a Fukushima hospital, will later be sent to the National Institute of Radiological Sciences in Chiba Prefecture, the agency said.

TEPCO said radioactive water may have seeped through the workers' radiation protective gear, causing radioactive materials in the water to stick to their skin. The burns are caused by direct exposure to beta rays, the utility added.

Following the incident, workers at the first and the basement floors of the No. 3 reactor's turbine building were told to evacuate the area.

The radiation levels the three were exposed to are this time lower than the maximum limit of 250 millisieverts set by the health ministry for workers tackling the ongoing emergency at the Fukushima plant. The accumulative amounts of radiation to which they have been exposed are also below this criteria, TEPCO said.

Usually in Japan, the upper radiation exposure limit for nuclear plant workers is set at 50 millisieverts per year, or 100 millisieverts within five years, but the level comes to a cumulative 100 millisieverts in the event of a crisis. The health ministry has further relaxed these standards to deal with the crisis in Fukushima, the worst in Japan.

With the latest exposure cases, the number of workers who have been exposed to radiation exceeding 100 millisieverts at the plant comes to 17, the operator said.

Kyodo News

A Japanese physicist, who asked not to be identified so as not to damage his relations with the establishment, said it was “ridiculous” that the workers had not been wearing full protective gear. 

A senior nuclear executive who insisted on anonymity but has broad contacts in Japan said that there was a long vertical crack running down the side of the reactor vessel itself. The crack runs down below the water level in the reactor and has been leaking fluids and gases, he said.

The severity of the radiation burns to the injured workers are consistent with contamination by water that had been in contact with damaged fuel rods, the executive said.

“There is a definite, definite crack in the vessel — it’s up and down and it’s large,” he said. “The problem with cracks is they do not get smaller.” 

(CNN) -- Since March 11, the six reactors at the Fukushima Daiichi nuclear power plant have been in various states of disrepair after being battered by a 9.0-magnitude earthquake and subsequent tsunami.

Here is the latest on the status of each reactor and what was being done to prevent further emissions of radioactive material.

Reactor No. 1

Pressure and temperature levels at the No. 1 reactor continue to fluctuate, though Hidehiko Nishiyama of Japan's nuclear and industrial safety agency told reporters Friday that the situation then appeared "rather stable."

While conceding that "controlling the temperature and pressure has been difficult," Nishiyama said there were indications that the pressure and temperature were both decreasing.

Authorities hope to begin injecting fresh water, rather than seawater as has been done, into the reactor's spent nuclear fuel pool.

According to the Japan Atomic Industrial Forum, a nuclear industry group basing its data on official government and utility information, the No. 1 unit's reactor core has been damaged, but its containment vessel was not. As of Friday, the reactor's cooling systems were still not operational.
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Still, the building was "severely damaged" by an earlier hydrogen explosion.

While electricity issues remain, lighting has been restored for this and the No. 2 reactors.

Reactor No. 2

Like with No. 1, there has been evidence of high radiation levels in spots in and around the No. 2 reactor -- though not as high as that of the No. 3 unit.

Nishiyama said Friday that authorities hope to start injecting fresh water (rather than the current seawater) into the reactor's core and spent nuclear fuel pool. The water is being pumped in to help cool down nuclear fuel rods and prevent the further emission of radioactive material.

Damage is "suspected" in this unit's containment vessel -- the only such vessel so compromised, according to the Japan Atomic Industrial Forum. The reactor's core is also thought to be damaged. But the building itself has only been "slightly damaged," the same group reports.

That said, the containment vessel pressure is considered "stable," the nuclear industry trade group reports.

Reactor No. 3

The water that three men stepped in while laying cable in the basement of the No. 3 unit's turbine building had 10,000 times the amount of radiation typical for that locale, Nishiyama said. The workers -- each of whom tested 170 or more millisieverts of radiation, including two with direct exposure on the skin -- were admitted Friday for four days of observation at Japan's National Institute for Radiological Sciences, a research hospital in Chiba.

He noted that the contamination likely came from the reactor's core, adding there's a possibility of "some sort of leakage." That potentially could come from a crack in the reactor core, though Nishiyama cautioned that there is no definitive answer yet on how the radioactivity got into the basement.

Despite the suspected damage to the reactor core -- something that isn't presumed at any of the other five reactors -- the nuclear safety official said there is evidence that pressure is somehow being maintained in the vessel, making it less likely there is a big gash.

"Radiation levels are high" in some locations in and around the reactor, Nishiyama said.

These issues, including the radiation in the water, are prompting authorities to consider "other routes" to address issues at the reactor without exposing workers to excess radiation. Nishiyama said that, as of Friday afternoon, there was no firm plan on workarounds.

Firefighters from Kawasaki, with assistance from the Tokyo fire department, sprayed water Friday on the No. 3 reactor and its spent nuclear fuel pool.

The building of the No. 3 reactor was "severely damaged" after an explosion caused by the buildup of hydrogen gas, reports the Japan Atomic Industrial Forum. Its core reactor is also damaged, its fuel rods are either partly or fully exposed. As to its nuclear spent fuel pool, reports are that the pool was "possibly damaged" and the water level has been low -- a reason for the repeated spraying.

Reactor No. 4

A concrete pump truck was used once again Friday to inject seawater into the unit's fuel pool.

Along with the Nos. 5 and 6 units, the No. 4 was offline on a scheduled outage when the earthquake hit, and as a result the reactor's water level and pressure are continued safe.

But its nuclear spent fuel pool was "possibly damaged," which is why authorities have said its water levels are low and why they've made repeated efforts to fill it up with seawater.

Reactor No. 5

The No. 5 unit appears safe, for now, Nishiyama said. Its capability to cool the fuel rods in the spent fuel pool is working again, according to the Japan Atomic Industrial Forum.

As with units Nos. 4 and 6, this reactor was off on a scheduled outage when the quake hit and there are no major issues with the reactor and core itself. The nuclear spent fuel pool is thought to be functioning, aside from continued concerns about powering its cooling system to ensure that the fuel rods contained within remain cool.

As with unit No. 6, three holes were punched in the building earlier in order to relieve pressure and prevent a hydrogen explosion.

Reactor No. 6

The No. 6 unit appears safe, for now, Nishiyama said. Its capability to cool the fuel rods in the spent fuel pool is working again, according to the Japan Atomic Industrial Forum.

The No. 6 reactor was offline when the tsunami struck, and there are no major concerns about the structure or safety of its core or containment vessel. The nuclear spent fuel pool is thought to be functioning, aside from continued concerns about powering its cooling system to ensure that the fuel rods contained within remain cool.

As with unit No. 5, three holes were punched in the building earlier in order to relieve pressure and prevent a hydrogen explosion.

CNN NEW

TOKYO (Reuters) - Hiroyuki Nishi narrowly escaped death the day the monster earthquake struck Japan two weeks ago when a 200-ton hook on a crane came crashing down a mere 6 feet from him during the convulsions.

Now, the place where he cheated death -- inside reactor No. 3 at the crippled Fukushima Daiichi nuclear power plant -- is the reason he can't go home. Reactor No. 3 has been leaking high radioactivity and its operator, Tokyo Electric Power Co (TEPCO), can't say why. Days of dousing it with water in a desperate attempt to cool its used but probably exposed fuel rods have been inconclusive. Workers who got radioactive water on their shoes were hospitalized.

The Japanese government has imposed a 20-km (12-mile) evacuation radius around the plant because of the radiation danger, and Nishi's hometown of Minamisoma sits right on the cusp to the north. Nishi, 31, works for a contractor that did construction jobs around the nuclear power plant and inside its six reactors. On March 11, he was inside the reactor building directing a ceiling-mounted heavy-duty crane, moving scaffolding material to be taken outside. At 2:46 p.m. the quake struck with titanic force, at magnitude 9.0 the most massive earthquake Japan has ever recorded. It was as long as it was colossal, lasting more than two minutes, and also led to a huge tsunami. More than 27,000 people are dead or missing.

"I felt things shaking, and then it went crazy," Nishi recalled in an interview. "I was shouting, Stop! Stop!" Then the lights went out, leaving about 200 workers inside the reactor in near-darkness since the structure has no windows.

A small red emergency light started blinking. "Then some kind of white smoke or steam appeared and everyone started choking," Nishi said. "We all covered our mouths and ran for the door." But the door leading outside was locked, shut down automatically during the temblor to contain any leakage. The workers were stuck. "People were shouting 'Get out, get out!'" Nishi said. "Everyone was screaming." Pandemonium reigned for about 10 minutes with the workers shouting and pleading to be allowed out, but supervisory TEPCO employees appealed for calm, saying that each worker must be tested for radiation exposure.

CRESCENDO TEPCO began testing workers but the crescendo grew. Nishi recalled angry shouts from among the workers including expletives from a couple of Canadians. "We were shouting that the reactor structure was going to collapse or that a tsunami might come," Nishi recalled. Radiation exposure was the last thing on their minds. Eventually, TEPCO workers tested about 20 people before giving up and throwing open the doors.

The freed workers sprinted for their cars or to higher ground. Nishi ended up in his car with a co-worker who also lived in Minamisoma, about a half-hour drive away. They made it out of the nuclear plant in time to avoid the killer tsunami but were hardly prepared for the drive home. It was like a journey through an apocalyptic landscape. Traffic was jammed, and strong aftershocks made the car flail repeatedly. Nishi and his friend's cellphones went off constantly with "earthquake-coming" alerts, and the car radio blasted frantic reports of unspeakable damage from the tsunami and warnings of further tidal inundations. They passed wrecked buildings, cars that looked as though they had tumbled from bridges, and dead horses and cows by the roadside. Several homes crumbled before their eyes from aftershocks.

Nishi couldn't get through to his wife Azusa, 27, by phone. He was panic-stricken about not only his nine-month-old son Tsubasa at home but his 6-year-old son Hayato who was at kindergarten at the time the earthquake hit. "I was shouting at the phone: Please, please connect!" he said. Nishi and his colleague lapsed into fatalistic doomsday conversations. "We talked about three possibilities," he said. "That our entire families had died. That some had died and some lived. Whether our houses were still there." The thought that all family members might have survived didn't enter into their minds. "Seeing what was happening, we just knew it wasn't possible," Nishi said. As they finally got to Minamisoma, it became clear that Nishi's colleague's home couldn't be standing. His wife, 7-month-old son and parents making it out seemed remote. Nishi dropped his friend off and went to his own home. It was partially collapsed and in a shambles from the earthquake, but the tsunami had stopped 100 meters (yards) short of the house, which was four km (2.5 miles) inland. No one seemed to be home. Loudspeakers in town told people to head to evacuation centers; the closest one was at Kashima Middle School, the same junior high school Nishi had attended. Nishi made his way there, and at around 7:30 that night he arrived at the school -- and found his family there, intact, including his mother. "I saw my wife, and I was just so, so happy," he said, audibly choking up. "I let loose with my emotions. I kissed my kids' faces all over; I touched their faces everywhere. I kept telling them, 'I'm so happy you're alive.' There were lots of tears." The next day Nishi went to his home and found he could squeeze in the door. He hurriedly collected a few items: warm clothes, instant noodles, bottled water.

His colleague's parents are missing and presumed dead, but his wife and son survived. Nishi and his family have relocated to an apartment in neighboring Yamagata prefecture. He gets a government allowance for three months, but it's only for housing. He longs to go back to his house, and retrieve precious family photos and his beloved surfboard and wetsuit.

He also has mixed feelings about his work at the nuclear plant. "I had work and got paid, so I don't think badly of it," he said. "But, they said over and over that it was safe. I just want to ask why."

(Editing by Raju Gopalakrishnan)

Japan's biggest nuclear utility, Tokyo Electric Power (Tepco), admitted that it has found cracks in the pipes of two reactors that were destined to burn mixed oxide (Mox) fuel made at BNFL's Sellafield Mox Plant in Cumbria.

Details of the cracks have been kept secret for more than two years. Tepco has shut down the two reactors at Fukushima Daiichi and Kashiwazaki Kariwa and has delayed restarting them until hundreds of pipes are checked.

Independent UK

Aug. 18 (Bloomberg) -- Tokyo Electric Power Co., Asia's biggest power producer, said some radioactive water spilled from storage pools into ventilation systems of three nuclear reactors because of an earthquake that shook Japan two days ago. 

``The amount of radiation found in the leaks was not very dangerous,'' spokesman Keiichi Yoshida said by phone today. ``In all cases, the water was easily cleaned up, and none of it escaped outside the plants.'' 

A total of 24.5 liters (6.5 gallons) of water leaked, the Tokyo-based utility said in a statement yesterday.

Bloomberg

Tepco admitted the 'dishonest acts' in a press release issued in late October, During the two annual inspections at Fukushima Daiichi 1 (Fukushima I-1), plant staff knew that the containment leak rate was too high. When government inspectors carried out the leak tightness test the staff injected air via the main steam isolation valves to reduce the leak rate. Reportedly the actual rate was 2 per cent per day compared to the allowed maximum of 0.45 percent per day. By manipulating the valve, the rate was reduced to 0.12 per cent per day.

Tepco-manipulated-test-results

No. 1: Contaminated water in the turbine structure contains 10,000 times the radiation of regular cooling water, NHK said. The company has started removing contaminated water from the basement of the turbine building and will prepare more pumps to drain the water, the agency said. The unit has been damaged since a March 12 hydrogen explosion destroyed the building’s walls. The seriousness of the reactor’s threat to safety is rated level five on an international scale of 1-7.

No. 2: Contaminated water in the turbine structure contains 10 million times more radiation than normal cooling water, NHK said. The company plans to remove contaminated water as early as today, the agency said. The company plans to start using freshwater on fuel pool from March 28, the agency said. The containment chamber may have been damaged in a March 15 explosion, and a power cable was reconnected to the unit on March 19. The reactor is rated a level-five threat.

No. 3: Contaminated water in the turbine structure contains 10,000 times the normal radiation, NHK said. The company is considering ways to remove the contaminated water, the agency said. A March 14 explosion damaged the unit’s fuel cover. The reactor is rated a level-five threat.

No. 4: The company plans to spray water in the spent-fuel cooling pool this afternoon, the Nuclear and Industrial Safety Agency said. The agency said on March 17 there may be no water in the pool. It’s rated at three on the threat level. This reactor was undergoing maintenance when the earthquake hit.

No. 5: The unit was idle for maintenance before the earthquake.

No. 6: The reactor achieved cold shutdown at 7:27 p.m. on March 20 when the temperature fell below 100 degrees Celsius, the company said. A backup generator was fixed March 19, according to a company press release. The unit was idle for maintenance before the earthquake.

Source: Bloomberg Business

GRS, a German nonprofit that advises the German government on nuclear safety, issues a daily compilation of data from many of the key primary sources, including available daily temperature, pressure and water level data. 

The last two reports have contained the dose rates in the containment and pressure suppression pool areas for the Fukushima reactors.  When the first report came out, there was discussion here that the IAEA information cited isn't in the IAEA reports and was suspect.  However, GRS provided the same sort of information the second day, and doesn't look like the sort of organization that would make this up and attribute it to the IAEA. 

According to IAEA information of 23-03-2011 at 6:00 h CET (14:00 h local time in Ja- pan), dose rates are available for the containments and the pressure suppression pools  of Unit 1-3 of the Fukushima Daiichi plant. 

Fukushima Daiichi  Containment  Pressure suppression pool 

Unit 1                    46 SV/h       31.6 SV/h 

Unit 2                    52 SV/h       1.8 SV/h 

Unit 1    40.9 SV/h    25.8 SV/h 

Unit 2    47.7 SV/h    1.36 SV/h 

Unit 3    53.3 SV/h    1.45 SV/h

Questions for the experts.  (I don't recall TheRedneck discussing this, but perhaps I missed it.) What would the dose rates be in the containment area and the pressure suppression pool during ordinary operations prior to the quake? 

Does this data help interpret the sources of radiation, assuming there is water interchange so that water internal to the reactor is escaping into the circulating cooling water? 

What does the extremely high dose rate in the pressure suppression pool for Reactor 1 compared to Reactors 2 and 3 tell us about its internal condition? 

Are the reported dose levels virtually prohibitive for work in these areas even with extensive protective gear? 

Does this data tell us much about whether resumption of work is feasible in areas near the reactors, given the uncertainty as to conditions? 

Compilation of jetstream monitoring various emissions 

This just in to the City Desk … the state Department of Public Health announced today they have detected low levels of radiation in Massachusetts rainwater, likely from the nuclear fallout from Japan’s crippled Fukushima Dai-ichi nuclear power plant.

As you can read below, there’s no public health threat, but it does illustrate the severity of the nuclear crisis in Japan. Here’s the release …bostonherald.com...

The concentration of I-131 was 79 pCi/L (picocuries per liter). The precipitation sample was taken during the past week, with results available today following analysis and confirmatory testing by the DPH Radiation Control Program. Similar testing in other states, including California, Pennsylvania and Washington, has shown comparable levels of I-131 in precipitation samples. Federal officials have indicated that such findings would likely be found in multiple locations across the country, with some variation due to weather patterns.

ETA:
U.S. National Institutes of Health National Cancer Institute www.cancer.gov...

Information and resources for Americans exposed to I-131 (a form of radioactive iodine) through fallout from above-ground nuclear testing in the 1950s and early '60s.

San Francisco Rainwater: Radiation 181 Times Above US Drinking Water Standard

Originally posted by SDoradus

The U.S. Nuclear Regulatory Commission concluded in the late 1980s that the General Electric designed Mark I reactors, like those used at Fukushima, required safety modifications.

The risks they flagged, and that Tokyo did not heed, would come back to haunt Japan in the Fukushima crisis.

First, U.S. researchers concluded that a loss of power at one of the nuclear plants would be one of the "dominant contributors" to the most severe accidents. Flooding of the reactor building would worsen the risks. The NRC also required U.S. plants to install "hard pipe" after concluding the sheet-metal ducts used in Japan could make things much worse.

"Venting via a sheet metal duct system could result in a reactor building hydrogen burn," researchers said in a report published in November 1988.

In the current crisis, the failure of the more vulnerable duct vents in Fukushima's No. 1 and No. 3 reactors may have contributed to the hydrogen explosions that blew the roof off the first and left the second a tangled hulk of steel beams in the first three days of the crisis.

The plant vents, which connect to the big smokestack-like towers, appear to have been damaged in the quake or the tsunami, one NISA official said.

Even without damage, opening the vulnerable vents in the presence of a build-up of hydrogen gas was a known danger. In the case of Fukushima, opening the vents to relieve pressure was like turning on an acetylene torch and then watching the flame "shoot back into the fuel tank," said one expert with knowledge of Fukushima who asked not to be identified because of his commercial ties in Japan.

Tokyo Electric began venting the No. 1 reactor on March 12 just after 10 a.m. An hour earlier the pressure in the reactor was twice its designed limit. Six hours later the reactor exploded.

The same pattern held with reactor No. 3. Venting to relieve a dangerous build-up of pressure in the reactor began on March 13. A day later, the outer building - a concrete and steel shell known as the "secondary containment" -- exploded.   Continued...

Source: Reuters