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Fukushima Dai-ichi plant: Work stopped as steam rises from reactors # 2 and 3

March 21, 2011

Work to connect power cables to the No. 3 and No. 4 reactors was halted Monday at the crisis-hit Fukushima Daiichi nuclear power plant, after smoke rose from the buildings housing the No. 2 and No. 3 reactors, the plant operator said.

TEPCO said it had briefly evacuated its workers after grayish and blackish smoke was spotted at the southeast of the No. 3 reactor building around 3:55 p.m. above a pool storing spent nuclear fuel, though a blast was not heard.

The smoke stopped after 6 p.m., but TEPCO subsequently found that white smoke was rising through a crack in the roof of the building that houses the No. 2 reactor at around 6:20 p.m. The utility said later the smoke is believed to be steam, not from the reactor’s fuel pool. As the No. 3 reactor remains without power, smoke was not apparently triggered by an electricity leak or short-circuiting.

The government’s Nuclear and Industrial Safety Agency said no injuries were confirmed in the incidents and that there have been no major changes in the radiation levels at the site.

Before the smoke was detected, external power had reached the power-receiving facilities of the No. 2 and No. 5 reactors on Sunday, clearing the way for the plant operator to restore systems to monitor radiation levels and other data, light the control rooms and cool down the reactors and their spent-fuel storage pools. On Monday, TEPCO finished laying cables to transmit electricity to the No. 4 reactor, as a step toward resuscitating the power systems at the No. 3 and No. 4 reactors, according to the utility and the nuclear agency.

International Atomic Energy Agency Director General Yukiya Amano told a special meeting of its board of governors that the situation at the Fukushima plant ”remains serious, but we are starting to see some positive developments.”

Tokyo Electric Power Co. said it will resume the operation on Tuesday after observing the situation at the site.

 

 

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Fukushima Dai-ichi nuclear plant: Status as of Monday (21st) morning

March 21, 2011

Status of Fukushima Daiichi power station as of 09:00, March 21, 2011

Cooling continues and power is gradually being brought to all reactors. Systems and equipment are being checked. All units now have surface temperatures of less than 100 °C. Reactors # 5 and 6 have acieved “cold shutdown”.

External power reached the power-receiving facilities of the No. 2 and No. 5 reactors on Sunday.

The government is also preparing SDF tanks to remove radioactive rubble from around the reactors that has hampered operations as well as a truck with a concrete squeeze pump to pour water from a higher point.

Reactors # 5 and 6 have achieved the status of “cold shutdown”.

Developments at Fukushima Daiichi on March 21st

  • Injecting water to the spent fuel pool at unit 3 of Fukushima Daiichi by Tokyo Fire Department’s task force was finished at around 04:00 am this morning after 6.5 hours operation. Unit 3 has been sprayed with over 3,700 tons of water on Sunday and Monday.
  • Then, the Self-Defense Force conducted the operation of injecting water to the spent fuel pool at unit-4 from 06:37 am to 08:30 am this morning.
  • A construction company in Mie Prefecture voluntarily offers assistance for water injection at Fukushima Daiichi. The government emergency headquarters decided to accept the offer. The company’s 2 special vehicles and 3 operators departed last night to the site. The vehicles can inject water by using its 50-meter-long arm and pumps.
  • Ministry of Defense announced that the Self-Defense Force helicopter measured the surface temperatures of Fukushima Daiichi from the air and found that the temperature of all units are below 100 degrees C.
    • Unit 1: 58 ° C;
    • Unit 2: 35 ° C;
    • Unit 3: 62 °C;
    • Unit 4: 42 ° C;
    • Unit 5: 24 ° C;
    • Unit 6: 25 °C. (as of the afternoon on March 20)

Yesterday the Nuclear and Industrial Safety Agency reported that the pressure of the Reactor Containment Vessel at unit 3 of Fukushima Daiichi rose once (to 320 kPa as of 11:00 March 20th). TEPCO prepared to lower the pressure but concluded immediate pressure relief was not required. Monitoring the pressure continues (225 kPa as of 22:00 March 20).

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Fukushima Dai-ichi 19th March: “Nuclear crisis is abating step by step”

March 18, 2011

Saturday 19th March: Day 8 after the quake and tsunami

Geoeye before and after pictures from the New York Times

2330 JST (1530 CET): The spraying operation should have ended around now.

Internal cables are being completed.

1906 JST (1106 CET): A 6.1 magnitude quake about 20km down has hit Iberaki with shaking felt in Tokyo. No risk for a tsunami but the epicentre is not so far away from Fukushima.

1830 JST (1030 CET): The Chief Cabinet Secretary Yukio Edano said earlier today “The crisis is abating step by step”. No doubt he had his fingers crossed at the time. Worth bearing in mind that in spite of all the alarm and sensational reporting and alarmism, there are no deaths associated with the nuclear accident to date while the dead and missing from the quake and tsunami now number 20,000+. Some of the emergency workers (about 20) at the site have suffered some radiation exposure but at a relatively low level compared to Tjernobyl. Outside of the exclusion zone radiation levels are still miniscule.

Hidehiko Nishiyama, deputy director-general of the Nuclear and Industry Safety Agency, told reporters that a review of video shot from a helicopter and an on-the-ground check by a worker had confirmed that there is water in the spent fuel pool.

A seven-hour long water spraying exercise is ongoing. The current plan seems to be to start feeding power into reactors #1 and 2 early Sunday and also to reactors # 3 and 4 later on Sunday. Could be coincidence but it seems that all planned actions on the power reconnection are always preceded by a water spraying exercise and never carried out while water spraying is ongoing. Perhaps the water spraying reduces local radiation levels so as to permit longer working shifts in the exposed zones. The current spraying exercise will continue till about 2300 local time.

1730 JST (0930 CET): According to government quake-hit Oshika Peninsula moved 5.3 meters, dropped 1.2 meters.

1600 JST (0800 CET): Spraying has restarted and will continue now for 7 hours. SDF troops and fire fighters are together trying to set up a round the clock spraying capability. Reactors #5 and 6 are each being cooled by one of their own diesel powered pumps.

Press Conference by Chief Cabinet Secretary : Reactors # 1, 2 and 3 have been subject to sea water cooling and are somewhat stable. We believe the spray water has reached the reactor #3 spent fuel pond and this has also stabilised and spraying will continue for reactors #3 and 4. Further actions using additional equipment are planned once the situation has stabilised. The crisis is abating step by step.

Within Fukushima and Iberaki prefectures some milk and spinach had radiation levels above the limits set by the Food Safety Law. Today 6 samples of spinach had high radiation levels. Further investigations will continue and the prefecture governments will prevent transport of these.The radiation levels in these products would mean that continuous consumption for a year would be just equivalent to a CT scan. The detected levels are above permissible levels but are not an immediate health hazard. Detailed information will be provided by the Ministry of Food.

1530 JST (0730 CET): While the new high voltage power line is connected to a transformer within the plant perimeter, the path from there to the reactor#1 and 2 transformers was blocked by debris and an extra 1500 m of power line around the perimeter of the plant to the reactor transformers has to be installed. This power is unlikely to be switched on before late Saturday. The cooling pumps which were subbmerged by the tsunami have still to be checked out.

1500 JST (o700 CET): A diesel cooling pump was restarted at reactor #5 a few hours ago and the temperature in reactor #5’s spent fuel pond has decreased. A diesel generator at reactor#6 has also been restarted.

The radiation level at the west gate of the plant, located about 1.1 kilometers west of the No. 3 reactor, was relatively high at 830.8 microsieverts per hour at 8:10 AM but fell to 364.5 microsieverts at 9:00 AM.

Starting at noon some 30 tons of water were sprayed onto reactor #3.

Engineers have bored holes in the roofs of the buildings housing # 5 and 6 to avoid any hydrogen explosions.

The new power line is still not fully connected or in operation yet but the hope is that power can be turned on later today to reactor #2.

0800 JST (0000 CET): Checks are presumed to be ongoing before any attempt to turn power back on. Not only must the equipment integrity be checked but the possibility of short circuits and any volatile matter which could ignite must be eliminated as well. The next round of spraying will be at noon.

0600 JST (2200 CET): Reuters reports: Working inside a 12 mile evacuation zone at Fukushima, nearly 300 exhausted engineers were focused on trying to restore power at pumps in four of the reactors.
Another 1,480 meters (5,000 feet) of cable are being laid inside the complex before engineers try to crank up the coolers at reactor No. 2, followed by 1, 3 and 4 this weekend, company officials added. Should that work , it will be a turning point. “If they can get those electric pumps on and they can start pushing that water successfully up the core, quite slowly so you don’t cause any brittle failure, they should be able to get it under control in the next couple of days,” said Laurence Williams, of Britain’s University of Central Lancashire.

0500 JST (2100 CET): TEPCO has checked out the power line upto the receiving point at reactor #2 and confirmed that power can now be supplied. Presumably some equipment checks must be done before turning the power on.

0400 JST ( 2000 CET 18th): TEPCO says it has now connected an external power line to its stricken plant and would first supply reactor 2 because it is less damaged, Reuters reports. The power is from Tohoku Electric.

0230 JST (1830 CET):  TEPCO has appointed Vice President Norio Tuzumi and Managing  Director Akio Komori to be stationed at Fukushima City and J Village respectively from March 22, 2011. Tuzumi will be responsible for ensuring that TEPCO takes in the opinions and views of the loacl people and Komori will be responsible for safety and the prevention of further damage.

The operation to douse the overheating fuel rods at Fukushima resumed early on Saturday. Five specially-equipped engines from the department poured seawater for 20 minutes so as (to allow the work for connecting the power line to continue) says NHK.

0000 JST (1600 CET):  Graham Andrew of the IAEA: “The situation at Fukushima Daiichi nuclear power plants remains very serious but there has been no significant worsening since our last briefing” on Thursday.

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TEPCO was ready to give up and abdicate on 14th March

March 18, 2011

The Mainichi Daily News carries this story. Even in the unprecedented situation after the quake and tsunami and with the nature of the radiation risks involved the reaction of some of the TEPCO employees is understandable; but that TEPCO as a Corporation was ready to give up and ask the SDF to bear all the risks smacks of Corporate cowardice and does not say much for the Corporation’s values:

Tokyo Electric Power Co. (TEPCO) told the government on March 14 that it wanted to withdraw all of its workers from the Fukushima No. 1 nuclear power plant, it has been learned.

TEPCO’s suggestion came two days after a cooling system failure caused by the March 11 quake and tsunami triggered a hydrogen blast at the plant’s No. 1 reactor. Though Prime Minister Naoto Kan rejected the proposal, the finding suggests that the power company was aware from an early stage that damage at the plant could develop into a nuclear disaster exposing workers to high levels of radiation. It is believed that TEPCO was prepared to let Japan’s Self-Defense Forces and the U.S. military handle the situation.

Several government sources said that TEPCO officials told Chief Cabinet Secretary Yukio Edano and Economy, Trade and Industry Minister Banri Kaieda over the phone that the company wanted to withdraw all of its workers. Both government officials turned down the requests and reported them to Kan.

Shortly after 4 a.m. on March 15, Kan summoned TEPCO President Masataka Shimizu to the Prime Minister’s Office and told him pulling out was not an option. He added that a joint countermeasures headquarters would be set up.

Afterwards, the prime minister visited TEPCO’s head office in Tokyo and said, “This is not a matter of TEPCO going under; it’s about what will become of Japan.”

Government officials confirmed that TEPCO’s suggestions on the night of March 14 indicated the company wanted to pull out all of its workers.

At the same time complaints are smoldering within TEPCO over Kan’s response. TEPCO officials said that the company has 4,000 to 5,000 workers at the plant, including those from cooperating firms, but now only about 300 remain. They are working to control and restore power-generation stations.

“Saying, ‘I won’t allow you to pull out,’ is like saying, ‘Get exposed to radiation and keep going until you die,'” one member of the company commented.

TEPCO could well have allowed all workers who wished to do so to leave the plant while bearing their corporate responsibility. I am quite sure that there would have been many TEPCO employees who would have volunteered for emergency operations. Masataka Shimizu and TEPCO are no Samurai – but perhaps that is no longer a reasonable expectation. It does seem as if the military are now in control.


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Fukishima Dai-ichi status updates on Thursday 17th “It is not going to be another Tjernobyl”

March 17, 2011

2000 CET: From the IAEA – Engineers plan to reconnect power to unit 2 once the spraying of water on the unit 3 reactor building is completed, the statement says. “The spraying of water on the unit 3 reactor building was temporarily stopped at 1109 GMT (2009 local time) on 17 March. The IAEA continues to liaise with the Japanese authorities and is monitoring the situation as it evolves”

1900 CET: The installation of the new high voltage power line to the Fukushima Dai-ichi nuclear plant and the restarting of the cooling systems seems now to be the critical and perhaps decisive step. Hopefully this can be done on Friday.

A Russian nuclear expert has said Japan should concentrate its efforts on restoring power to the Fukushima nuclear plant – rather than trying to cool its reactors by dropping water from helicopters. “One can only put out forest fires like this, by pouring water from helicopters. It is not clear where this water is falling,” Gennady Pshakin from the Institute of Physics and Power Engineering in the city of Obninsk told Reuters. “They need to start circulation pumps, at least one, maybe not at a full capacity, but I am not sure they have enough power. Diesel generators and mobile power stations which they sent there do not have enough capacity.” He added that it was not going to become another Chernobyl, saying that it was a “totally different situation”.

1700 CET: About 300 tons of water has been sprayed so far by helicopter and fire trucks. It is now 1 am Friday in Japan and there is little fresh news. But this is a case of “no news is good news”. There are no reports of any increased radiation levels but this kind of “stability” can be deceptive.  Helicopter water drops are planned again for Friday. The power line to restore high voltage power is still being installed and is taking longer than expected but is still expected to be ready on Friday. The cooling systems still have to be repaired before they can be restarted.

So far in terms of death and destruction the Fukushima nuclear plant is a pinprick compared to what has happened further north. But the spectre of Hiroshima and Nagasaki in Japan and of Tjernobyl elsewhere is probably what leads to the imbalance in the coverage. But unfortunately it is probably diverting some attention and resources from those in need.

1400 CET: At least 20 of the workers risking their lives at the Fukusima Dai-ich nuclear plant are suuffering from exposure to radiation.

Water shot out from the military trucks seem to have reached their target judging from the steam that was generated which in turn means that some cooling must have occurred. Apparently the military trucks are more effective than the fire trucks since the water cannons can be operated from within the safety of the cab. The effect on radiation levels is small so far.

They are hoping to connect the plant to external power during Thursday.

1240 CET: Breaking – Radiation levels have shot up after the shooting of water from water cannon. This may mean that the water is reaching its target and is evaporating on contact with the overheated spent fuel.

TEPCO Press conference.  Tepco spokesmen mainly repeat questions but provide no answers. One said that they had existing procedures in the Crisis Management Plan and they followed all procedures.  The spokesman only gave me the impression that since this accident is not in the book they had no idea what to do. Hardly any new information. No idea how much water the helicopters dropped. No information on the progress of the new power line. No information about the use of water cannon for cooling. A generally inept performance by TEPCO.

Some history from Reuters about TEPCO:

Five TEPCO executives resigned in 2002 over suspected falsification of nuclear plant safety records and five reactors were forced to stop operations.

In 2006, the government ordered TEPCO to check past data after it reported finding falsification of coolant water temperatures at its Fukushima Daiichi plant in 1985 and 1988, and that the tweaked data was used in mandatory inspections at the plant, which were completed in October 2005.

1200 CET: First attempt with the police riot truck water cannon was broken off due to high radiation levels. Another attempt is being made to shoot cooling water into the spent fuel ponds starting about 30 minutes ago.

The risk for a blackout in Tokyo seems to have been averted as the the evening load period comes to an end.

1000 CET: So far Tokyo has averted a blackout situation – but demand came close to the limit.

Radiation readings on this Ministry of Education, Culture, Sports, Science and Technology (MEXT) site.

The Defence Minister said that he “expected” the cooling water actions to “be successful”.  The water cannon fire trucks are all from the Tokyo police or from the SDF. This sounds as if the cooling efforts have now been taken away from TEPCO and handed over to the military. TEPCO seems to be continuing with efforts to restore power to the plant with a new power line.

0900 CET: No further word about the fire trucks and the water cannon. 11 more fire trucks are on their way.

An unprecedented massive blackout could take place in Tokyo on Thursday evening. Trains have been asked to reduce services and the authorities are asking for all to avoid using power if possible.

0800 CET: US unmanned aircraft from Guam have taken pictures over the plant which have been supplied to Japan. None of the evacuees from the area have needed decontamination says Fukushima prefecture.

TV pictures of the helicopter operation show much of the water spray missing the target buildings.

Kyodo News reports Japanese Government irritation with US statements:

Gregory Jaczko, chairman of the U.S. Nuclear Regulatory Commission, told a congressional hearing, ”There is no water in the spent fuel pool and we believe that radiation levels are extremely high, which could possibly impact the ability to take corrective measures.”

But a Ground Self-Defense Force chopper, which doused the overheating spent nuclear fuel pool with water Thursday morning at the No. 3 reactor, found that water is left in the pond at the No. 4 unit, according to the plant operator Tokyo Electric Power Co.

0700 CET: SDF helicopters have made 4 sorties for dumping water on reactor #3. There is still some water left in the reactor #4 spent fuel pool. Helicopters had lead plates installed for protection during the operations today. Radiation decreased only very slightly as a result and no further helicopter sorties are planned today. The riot police water cannons are expected to be used shortly. Each truck carries only 4 tons of water which is discharged in just one minute. This will require many refillings of the trucks and will take time. Spent fuel pools at reactors #3 and 4 are the priority. For reactors #5 and 6 temperatures are increasing but slowly and boiling will not occur for a few days yet.

The new power transmission line is still being installed. Progress is hindered by having to limit the time workers can spend within the plant. To reactivate the plant’s cooling systems will need the repair of some of the pumps.

0000 CET (midnight): A new power line is being laid to the Fukushima Daiichi plant to help restore the reactor cooling systems: Tokyo Electric Power Company (Tepco) spokesman Naoki Tsunoda has said it is almost complete, and that engineers plan to test it “as soon as possible”, according to the Associated Press. Reviving the electric-powered pumps might allow the engineers to finaly cool the overheated reactors and spent fuel storage ponds.

The IAEA has released information about the temperature of the water in the spent fuel storage pools inside reactors 4, 5 and 6 at Fukushima Daiichi. Spent fuel that has been removed from a nuclear reactor generates intense heat and the water is usually kept below 25C. The IAEA says that the temperature of the pool at reactor 4 was 84C on Tuesday morning. On Wednesday morning, it was 62.7C at reactor 5 and 60C at reactor 6. Current reports say the pools at both reactors 3 and 4 are boiling. Reactor 4’s pool may even be dry.

Kyodo News says that Tokyo police plan to use a water cannon truck to attempt to cool a spent fuel rod pool Thursday in a bid to contain the disaster at the troubled Fukushima No. 1 nuclear power station in Japan.

The government earlier studied a plan to deploy Ground Self-Defense Force choppers to spray water over the spent fuel pools, but the Defense Ministry said Wednesday afternoon it had given up on the idea due to the high radiation level.

The U.S. military, meanwhile, will operate a Global Hawk unmanned high-altitude reconnaissance aircraft, possibly on Thursday, to take images of the inside of the building that houses the No. 4 reactor, according to Japanese government sources.

Status by Kyodo News:

Among the six reactors at the Fukushima No. 1 nuclear plant operated by Tokyo Electric Power Co., part of the No. 2 reactor’s containment vessel, key to enclosing harmful radioactive substances, suffered damage in the pressure-suppression chamber connected to the vessel following Tuesday’s apparent hydrogen explosion.

An estimated 70 percent of the nuclear fuel rods have been damaged at the plant’s No. 1 reactor and 33 percent at the No. 2 reactor, Tokyo Electric said Wednesday.

The cores of the No. 1, No. 2 and No. 3 reactors are believed to have partially melted with their cooling functions lost in the wake of Friday’s magnitude 9.0 earthquake and tsunami.

The government’s Nuclear and Industrial Safety Agency said Wednesday that the water level had dropped in the No. 5 reactor, which was not in service when the killer quake jolted northeastern Japan, posing the risk of overheating. The agency said it will closely monitor data on the reactor to prevent the problems that occurred at other reactors.


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TEPCO delayed using sea water for cooling until instructed to

March 16, 2011

1700 CET: The water cannon fire truck has arrived on site but using the scatter-gun approach of helicopter sprays and fire engines at a precision nuclear plant smacks of desperate measures. They are in the same class as praying for rain.

I hope I am wrong but it seems like the main strategy being applied by TEPCO is now one of “hoping for the best”.

A commentator on NHK World has said that TEPCO did not take the initiative to use sea-water cooling at Fukushima because of the damage it could do to any future plant operation and only did so when instructed to by the Ministry and the Government.

TEPCO (Tokyo Electric Power Company) is the owner and operator of the Fukushima Dai-ichi nuclear power plant. None of the reactors where sea water has been used for cooling are likely to ever operate again.

The commentator criticised TEPCO’s crisis management and said that TEPCO should have reacted faster. NHK World also reported that the radioactive plume of steam coming from reactor no. 3 on Wednesday morning was first noticed by a NHK helicopter team from 30 km away  and long before there was any news from TEPCO. When first contacted the TEPCO spokesman did not know what it was and whether it was smoke from a fire or a steam leak.

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Fukushima Dai-ichi situation worsening and TEPCO is unsure how to proceed

March 16, 2011

1100 CET: The SDF helicopter cooling attempt was aborted for high radiation levels above the plent. New cooling attempts will use a water cannon on a fire truck borrowed from the US military.

From Paris, the BBC’s Christian Fraser says that France’s decision to offer its Tokyo-based citizens the chance to leave is partially motivated by domestic political problems.

0830 CET: Japanese TV reports that an SDF helicopter has taken off to spray water onto the plant. Helicopter spraying will be difficult to direct accurately and was thought to be a “last resort”. This suggests that other options are not feasible.

It is snowing in Fukushima.

0730 CET: Some workers have returned as radiation levels have fallen at the Fukushima Dai-ichi plant. While the Nikkei has risen some 6%, TEPCO shares have tanked. They were untraded but were bid down by the daily limit and are down 24.7%.

The operation could take on a military footing and responsibility could shift from TEPCO to the military. The Japanese Defence Minister has just said that if cooling efforts fail, the SDF would move in and SDF helicopters would spray water onto the plant.

TEPCO press releases are worthless and give virtually no information and the main source of public information is by the Chief Cabinet Secretary’s Edano’s press conferences. He himself is  impressive and generates some trust but it means that all information is being “politically” vetted so as not to be too alarmist. But just the filtering of information itself leads to assumptions (which may or may not be justified) that the actual information is worse than is being released. TEPCO’s communications and press conferences are not impressive.

Status at 0600 CET 16th March:

Work at the reactors may have stopped because radiation levels were too high. Radiation is fluctuating and has reached high levels at times. Levels were being reported in milli Sieverts(mS) rather than micro Sieverts (μS). For short periods levels upto 11 mS (11,000 μS). The normal working limit of 100 mS was raised 3 days ago to 250 mS and levels have been higher in parts of the plant.

The Fukushima Dai-ichi nuclear plant is being continuously subjected to new problems. All problems are unprecedented in the wake of the quake and the tsunami but TEPCO’s ability to cope is now raising cause for concern. Personnel from Toshiba, the manufacturer of the plant, have been called in by TEPCO. The initial plant design was to withstand earthquakes of magnitude 8.2 and it has been through a magnitude 9.0 quake some 15 times stronger than the design value. But the height of the tsunami wave was something not designed for. TEPCO spokesmen are getting testy when questioned and this is also an indication that they are frustrated and confused.

I have revised my view that TEPCO was in control of the situation. TEPCO seems to be unsure how to proceed.

Reactor #3 containment vessel is damaged and emitting steam (smoke?) and radiation. TEPCO does not know what it is. Workers near the central control room were evacuated temporarily(?). Workers are evacuated at levels higher than 259 Milli Sieverts.

Reactor #4 spent fuel pool is getting dangerous again. Pictures of the fire on 15th here were shown by TEPCO. It seems as if radiation levels here are also too high for workers to approach and attempt cooling. Winds and/or radiation levels are preventing the use of helicopters to dump water onto the reactor#4 spent fuel pool through a hole in the building roof. No other way to get cooling started seems to have been found.

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The Great Sendai Quake: Fukushima Dai-ichi reactor no.2 still critical

March 14, 2011

2230 CET: 0617  local time — Chief Cabinet Secretary Edano says that reactor No.2 remains unstable. As of 0300 local time on Tuesday, pressure inside the reactor container had dropped and it was believed seawater had been pumped in succesfully, Tepco said, according to the Kyodo news agency. However, Tepco admitted that it had not yet been able to confirm that water levels inside the reactor had risen. The fuel rods were fully exposed at 2300 local time on Monday night.

2000 CET: Japanese media are concentrating on human stories and playing down the nuclear danger. Foreign media seem to be competing to see who can be most alarmist. The truth is probably somewhere in between.

It is now 4 am on Tuesday in Fukushima and Kyodo News reported at 0346 local time that sea water cooling of reactor no.2 has restarted. It has been about 4 hours since the announcement of exposed fuel rods and about 3 hours since the faulty valve was reported fixed. Since it is unclear how long it will take to get the fuel rods fully immersed again, this second exposure of the fuel rods could be significantly longer than the 2.5 hours of the first exposure. Once again with very hot fuel rods the cooling water will first evaporate and pressure could rise. With every venting of steam there will be some radiation leakage.

1700 CET:  It seems the faulty valve on reactor no.2 for steam venting and which prevented the pumping in of cooling water has been accessed and fixed.

TEPCO reported that when reactor no.2 at Fukushima Dai-ichi nuclear plant released steam earlier on Monday radiation levels were found to be twice the maximum levels previously detected, but the levels dropped sharply. The radiation levels at the front gate of the power plant were found to be 760 μS at 9:35 p.m.; 3,130 μS two minutes later; and 400 μS by 10:15 p.m.

1600 CET: FLASH from Kyodo NEWS. Fuel rods at reactor No.2 fully exposed again.

From NHK – A confused report in translation but it may be that ingress of sea water is being stopped by a valve which has closed and is preventing the evacuation of air. Is the pressure too high inside the reactor?? A fear is that the water has evaporated in which case it could be a steam pressure building up.

Putin and Medvedev have stated that Russia has a moral responsibility to assist Japan. Oil and Gas supplies and upto 6,000 MW of electricity are being spoken of. It is now midnight in Sendai and temperatures are down to about 2 °C and will be dropping to freezing in a couple of hours.

1500 CET: Reactors Nos. 1, 2 &3 at Fukushima Dai-ichi are all cooling. But fuel rods at reactor no. 2 were fully exposed for 2.5 hours. Coolant levels are now rising. Some radiation leakage did occur and the fully exposed fuel rods must have partially melted. Reactor buildings 1 & 3 suffered hydrogen explosions which removed the roofs and part of the building walls.

Russian monitoring stations in the east of the country (Vladivostok) have not so far measured any increases of radiation.

There are no adverse reports concerning Reactors 4, 5 & 6.

Kyodo News:

Fuel rods at the quake-hit Fukushima No. 1 nuclear power plant’s No. 2 reactor were fully exposed at one point after its cooling functions failed, the plant operator said Monday, indicating the critical situation of the reactor’s core beginning to melt due to overheating.

The rods were exposed as a fire pump to pour seawater into the reactor to cool it down ran out of fuel, Tokyo Electric Power Co. said. The firm had reported the loss of cooling functions as an emergency to the government.

TEPCO said water levels later recovered to cover 30 centimeters in the lower parts of the fuel rods.

Later in the evening water levels had risen to cover 2m of the fuel rods.

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