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Media coverage dies as work resumes at Fukushima Dai-ichi – steam plumes did not raise radiation levels

March 22, 2011

Fukushima hysteria dies down as the media find that their alarmist and sensational reporting is not going to be sustainable.

Perhaps they will return their attention and their headlines to the victims of the earthquake and the tsunami in between the bombing raids on Tripoli.

As George Monbiot puts it in The Guardian:

As a result of the disaster at Fukushima, I am no longer nuclear-neutral. I now support the technology.

A crappy old plant with inadequate safety features was hit by a monster earthquake and a vast tsunami. The electricity supply failed, knocking out the cooling system. The reactors began to explode and melt down. The disaster exposed a familiar legacy of poor design and corner-cutting. Yet, as far as we know, no one has yet received a lethal dose of radiation.

Now George Monbiot’s views about energy in general, and renewables in particular, are usually quite ridiculous and ill thought through but  where he is absolutely right is of course that in spite of the headlines and the apocalypse scenarios, “no one has yet received a lethal dose of radiation”.

The work at Fukushima is difficult and hazardous  and it will test the courage and ingenuity of many – but it goes on even if all the headlines are gone     —– Kyodo News:

Work to restore power and crucial cooling functions resumed Tuesday morning at the crisis-hit reactors at the quake-stricken Fukushima Daiichi nuclear power plant, following suspension Monday after smoke was detected at its No. 2 and No. 3 reactors, its operator said.

Firefighters and the Self-Defense Forces also prepared to restart a mission later in the day to spray a massive amount of coolant water onto spent nuclear fuel pools at the No. 3 and No. 4 reactors, according to Tokyo Electric Power Co.

Although white smoke, possibly steam, was found to be continuously billowing from the buildings of the No. 2 and No. 3 reactors, the utility known as TEPCO found it does not obstruct electricity restoration work as radiation levels did not particularly surge at the site.

An external power source was connected to the No. 4 reactor in the morning, making it the fifth of the plant’s six reactors to have regained a power supply needed for the restoration of equipment such as a ventilation system to filter radioactive substances from the air and some measuring tools at the control room.

TEPCO aims to restore power systems to revive some key facilities such as data measuring equipment and functions at a control room by Wednesday for the No. 1 and No. 2 reactors and by Thursday for the No. 3 and No. 4 reactors, said Hidehiko Nishiyama, a spokesman for the Nuclear and Industrial Safety Agency, at a press conference.

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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 Sunday 20th March: Power has reached reactor#2, plant will be decommissioned

March 19, 2011

Day No. 9 since the quake and tsunami.

Media hysteria is abating as the crisis  abates and Libya take s over the headlines.  “It is becoming more probable by the day that public health consequences will be zero and radiation health effects among workers at the site will be so minor as to be hard to measure”.

On Saturday, workers were close to restoring power to cooling systems at a quake-hit Japanese nuclear power plant. Fire trucks sprayed water for nearly half a day on reactor No.3.

“The situation there is stabilizing somewhat,” Chief Cabinet Secretary Yukio Edano told a news conference.

2400 JST (1600 CET): Known status by IAEA:

It would seem that the current critical  actions with the nuclear plant are connected – for now – with the spent fuel pools.

Unit 1 experienced an explosion on 12 March that destroyed the outer shell of the building’s upper floors. No precise information has been available on the status of the spent fuel pool.

For unit 2, no precise information has been available on the status of the spent fuel pool. Authorities began adding 40 tonnes of seawater to the spent fuel pool on 20 March.

Concerned by possible loss of water in the Unit 3 spent fuel pool, authorities began spraying water into the building in an effort to replenish water levels. First, helicopters dropped seawater on 17 March, and every day since then, including today, emergency workers have sprayed water from fire trucks and other vehicles.

Emergency workers began spraying water into the Unit 4 building today.

Temperatures in the spent fuel pools of Units 5 and 6 have gradually returned to significantly lower temperatures.


2230 JST ( 1430 CET): Status – Fukushima No. 5, No. 6 reactors stable after cold shutdown.

External power was restored at 3:46 p.m. to the reactor #2. Work is now ongoing to  start trying to restore the system to monitor radiation and other data, light the control room and cool down the reactor and the reactor’s spent-fuel storage pool.

Water spraying by fire trucks continues for cooling the overheating spent fuel pools by throwing thousands of tons of water into the No. 3 and No. 4 reactor buildings. The operation is possible because apparent hydrogen explosions blasted the roofs and walls of the buildings.

As of 11:00 a.m., Tokyo Electric said the radiation level about 0.5 kilometer northwest from the No. 2 reactor dropped to 2,579 microsievert per hour, compared to 3,443 microsievert per hour at 2 p.m. Saturday.

1830 JST (1030 CET): Water spraying on reactor #4 again (2nd time today). Sounds like some danger of radioactive leakage from the spent-fuel pond is persisting.

Status summary (BBC)

  • Reactor 1: Fuel rods damaged after explosion. Power lines attached
  • Reactor 2: Damage to the core, prompted by a blast, helped trigger raising of the nuclear alert level. Power lines attached
  • Reactor 3: Contains plutonium, core damaged by explosion. Fuel ponds refilled with water in overnight operation, but pressure said to be rising again
  • Reactor 4: Hit by explosion and fire, temperature of spent fuel pond now said to have dropped after water spraying
  • Reactors 5 & 6: Temperature of spent fuel pools now lowered after rising dangerously high. Diesel generators powering cooling systems

1800 JST (1000 CET): Power has “been supplied” to reactor #2 says Kyodo news. It is not clear if the power now available has succeeded in starting up cooling pumps or just that power is now available at reactor #2. Nevertheless a huge leap forward.

The Fukushima Daiichi nuclear power plant is most likely to be decommissioned. ”Looking at the situation objectively, it is clear,” Chief Cabinet Secretary Yukio Edano said at a news conference, when asked whether the government plans to decommission the plant.

1600 JST (0800 CET): Current evacuation area not expected to change according to Japan’s Nuclear Agency.

Spent-fuel storage pools of the reactors No. 5 and No. 6 were cooled down to 37.1 °C and 41.0 °C, respectively, as of 7 a.m. Sunday.

More than 2,000 tons of water is believed to have been sprayed onto the No. 3 reactor’s pool, which has a capacity of 1,400 tons. Pressure at No. 3 reactor’s containment vessel suppression pool rose and plans to reduce pressure by venting were planned but the pressure stabilised and immediate work to reduce pressure at No. 3 reactor at Fukushima plant was deferred.

Fears of radiation release led to Ground Self-Defense Force spraying about 80 tons of water on reactor #4 for nearly one hour until 9:30 a.m., according to the Defense Ministry. Eleven fire trucks were used. Indications are that that water reached the pool.

Work to connect power and restart cooling pumps at reactor #2 is continuing.  It is planned to check the systems of the No. 2 reactor first. The building housing its containment was not damaged, which means it is hard to cool it down using water from outside.

0800 JST( 0000 CET): On Saturday and the early hours of this morning water spraying was carried out for a total of 13 hours (till about 5am on Sunday morning). The water temperature in the spent fuel pond of reactor #6 has fallen.

Power company engineers finished connecting the No.1 and No.2 reactors to external sources on Saturday evening.

Technicians seem to have attached a power cable to the No. 1 and No. 2 reactors, hoping to restore electricity later today prior to an attempt to switch the pumps on. Equipment checks are probably being conducted now.They aim to reach No. 3 and 4 soon after that.

The Register writes:

The situation at the Fukushima Daiichi nuclear powerplant in Japan, badly damaged during the extremely severe earthquake and tsunami there a week ago, continues to stabilise. It is becoming more probable by the day that public health consequences will be zero and radiation health effects among workers at the site will be so minor as to be hard to measure. Nuclear experts are beginning to condemn the international hysteria which has followed the incident in increasingly blunt terms.

0100 JST (1700 CET 19th): IAEA  press conference on the situation at the Fukushima Daiichi nuclear power plant. It hopes that power will be restored to reactor 2 today, which will then act as a hub to restore power to reactor 1. However it is not clear if water pumps have been damaged and if they will even work once power has been restored.

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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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Fukushima Dai-ichi diary for Friday 18th: Radiation decreasing – Is the worst over?

March 17, 2011

Today will be one week since the Great Sendai quake and the subsequent tsunami slammed north east Japan. Today will also be a fateful day for the efforts being made to cool the reactors and the spent fuel ponds at the Fukushima Dai-ichi nuclear plant. Though the nuclear plant incident causes much more alarm than anything else the quake and tsunami caused, it is worth bearing in mind that it is still just an incident at the nuclear plant. Radiation leakage has not itself caused any deaths or any destruction so far. If unchecked it has the potential of becoming a disaster but if the eforts to cool the reactor today succeed then it will remain at the level of a very serious nuclear incident caused by the quake and the tsunami.

It needs to be remembered that the massive death and destruction was caused by the quake and the tsunami and has resulted  in 20,000+ killed or missing and the wiping out of whole towns. Over 500,000 are displaced and some have lost everything they owned and many of their families. The nuclear plant incident should not be allowed to divert attention from the dire condition further north.

(Sources for my diary are mainly NHK, Kyodo, Asahi, Reuters, BBC, CNN, AFP, IAEA, JAIF and  a few private sources. Some interpretation of the news reports is necessary since they all seem to have some bias.)

2200 JST (1400 CET): Sendai Airport has been cleared with the help of US forces and is now being used to fly in relief supplies. Considering the pictures of the tsunami wave flowing across the airport one week ago, that itself is remarkable. It is still very cold tonight for the evacuees but warmer weather is expected tomorrow.

No further news conferences scheduled today and no further news which at least means no further deterioration. If power is restored to the nuclear plant during tonight the corner would have been turned, I think.

2100 JST (1300 CET): It looks like water spraying activities are over for the day and the focus is back on connecting the new high voltage power line. Current effort is to connect to a transformer in the reactor building but work times are very short since the radiation level here is about 20 milli Sieverts / hr. Tokyo police and fire fighters are trying to devise a system which allows spraying for long periods using the high capacity fire trucks designed for tall buildings.

A small reduction in radiation was observed when spraying was finished but assessment will take some time.

A description of the quake, tsunami and consequences for the plant operation are well described here.

1900 JST (1100 CET): The authorities are warning of tidal floods in the north east. Due to the earthquake, parts of the coast have sunk and in some areas tides could be 40cm higher than usual. Spring tides will last 8 days but flooding will be slow compared to the tsunami.

1800 JST (1000 CET): Japan’s nuclear safety agency is now calling it a level 5 incident at reactors 1, 2 and 3 of Fukushima Dai ichi, and a level 3 incident at reactor 4. I think the incident at reactor no. 4 where the problems with the spent fuel pond have been so turbulent could be reclassified later to level 4. Three Mile Island was classified at level 5.

The Japanese nuclear agency says it expects electrical cables to be connected at reactors 1 and 2 by Saturday morning.

1700 JST (0900 CET): 5.4 magnitude quake off Ibaraki subjecting Tokyo to some shaking as well.

General Electric has sent nuclear engineers to a Japanese emergency response centre where they are working with Tokyo Electric Power Co. GE designs nuclear reactors, including all six at the Fukushima Dai-ichi plant though the plants were constructed by Toshiba.

Reuters reports that US data collection flights have confirmed that contamination has not spread beyond the 30km zone established by the Japanese Government — which of course begs the question why the US established 80 km as the no-go zone  for their citizens and which was immediately adopted by many other countries. Abundant caution is no doubt the reason but some accompanying explanation would have helped to prevent some of the questioning of the Japanese imposed 30km zone.

Chief Cabinet Secretary Edano explained that the water spraying operations were being carried out in shifts to limit exposure and the further spraying operations would be continuing as the personnel were rotated. No details about the effects were yet available but it seemed clear that the water was reaching the target.

1600 JST (0800 CET): In Severe Accident Management, the key step and that which is being carried out now is the use of water for the removal of heat. More stringent operations include the use of sand or rubble or boron in some form to cover the radiating components. It is not impossible to even consider concrete. But all uses of solid materials would limit any further heat removal and would only come into play if heat removal was considered impossible.

An SDF spokesman said  “We think got water on the main part today” and “Troops doing the work only absorbed a few millisieverts at most” says the Daily Yomiuri. The Assistant Head of the SDF said that the radiation levels did not significantly hamper the water spraying operations.

1500 JST (0700 CET): 7 days have gone since the quake hit.

More fire trucks including US military trucks are on their way. It will probably take a few hours to make any evaluation of the effects of the water spraying. But the amount of steam rising suggests that the water was reaching its target. But the amounts contained in the sprays (total around 50 tons) is small compared to the capacity of the spent fuel ponds (about 1200 tons). Water spraying is to continue.

There are some 180 people working at the site and braving the radiation levels.

1414 JST: 2 more water jets can be seen – apparently the 3rd wave. Steam continues to rise and is “billowing” rather than a plume.

1410 JST (0610 CET): The strong plumes of steam(?) have subsided somewhat and are now more like clouds rising.

1406 JST: One wave of water spray with 2 trucks seems to be over and plumes of steam(?) can be seen rising from the reactor. Something is being cooled.

1400 JST (0600 CET): Water spraying has resumed at reactor no.3 by the SDF. Seven trucks are being used. The water jets are clearly visible from NHK pictures from 30km away and – at least by eye – are much more accurately directed onto the building than yesterdays helicopter drops.

1300 JST (0500 CET): Radiation levels have been consistently falling at one measuring point since the water spraying on Thursday evening. The measurement location is at one station about 1km west of reactor no. 2. The radiation reading at 5 a.m. Friday came to 279.4 microsievert per hour, compared with 292.2 microsievert per hour at 8:40 p.m. At around 9am this was down to 271 micro Sieverts. Thursday. It is not certain that this was due to the water spraying but the situation is at least stable and is not deteriorating. The trend is encouraging.

This morning the focus has been on the power line installation and on Friday at 2pm the water spraying will restart. It seems it was not possible to do both simultaneously. The SDF fire trucks will address reactor no.3 and police fire trucks will be working on reactor no.1. More fire trucks have been despatched from Tokyo. The performance of the trucks is such that helicopter water drops are not being considered. Over 30 trucks are expected to be in operation including trucks especially designed to fight fires in very tall buildings with a water discharge point 22m above street level. But water spraying is only a stop-gap measure and the real stability will only come once the cooling systems and water circulation has been restored.

The new power cables are in place but they now have to be reconnected to the cooling system pumps once the pumping systems have been checked out. Working shift durations are still restricted by the radiation levels. Reactor no.2 systems could be connected sometime during Friday night. Reactors no. 3 and 4 will be next to be reconnected and this is targeted for Sunday.

0600 JST: Summary of the status by Japan Atomic Industry Forum is here Fukushima status 2200 17th March

IAEA Slide show on BWR’s and the Fukushima status is here

18th March – 0500 JST (2100 CET 17th): The spraying of water by the fire trucks (and possibly even the helicopter water dumps) on the evening of the 17th did give some small but measurable decrease in radiation levels at the gate of the power plant. Spraying activities stopped at around 8pm on 17th and will resume this morning. Hopefully the high voltage power line which has now been laid upto the plant can be activated and the cooling systems brought back into operation today. This work will be slow since exposure to radiation leads to very short working shifts. This could take till tomorrow. This makes the spraying operations particularly critical for today to win the time necessary to get the power restored. The plan is for engineers to reconnect power to unit 2 once the spraying of water on the unit 3 reactor building gives some effect. The water spraying operations are being carried out by SDF and police personnel and TEPCO has even come in for criticism from the SDF for insufficient information which could have endangered their personnel.

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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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Reactor #4 at Fukushima Dai-ichi still unstable and could become critical.

March 15, 2011

While the situation at reactors # 1,  and 3 is stable with cooling by sea-water ongoing, the situation of the spent fuel pool at reactor no. 4 is still very serious and radiation leakage is still continuing. Reactor no. 2  suppression vessel is damaged and cooling is ongoing but the situation was not yet considered stable. Radiation levels are too high for technicians to get close to the reactor #4 pool to inject sea-water. The pool temperature was at 84°C and double the normal temperature of about 40 °C. The 20km zone evacuation around the plant was completed on Tuesday afternoon.

The option of trying to drop water by helicopter through a hole in the roof has been discarded since the pool is offset from the hole.

The use of specialised fire trucks with equipment which would allow water to be injected into the pool is being considered.

Getting fresh cooling water into the pool is now becoming very urgent and unless this is achieved the situation could become critical. As the temperature increases hydrogen could be produced and another hydrogen fire with an associated release of radiation becomes more probable.

Reuters reports that “Two workers are missing after Tuesday’s explosion at one of the reactors at a crippled Japanese nuclear plant, the country’s nuclear safety agency said.

The agency did not identify the missing workers, but said they were in the turbine area of the No.4 reactor at the Fukushima nuclear plant, which was damaged by last Friday’s earthquake and tsunami”.

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The Great Sendai Quake: Radiation surged from Fukushima Dai-ichi and now decreasing

March 15, 2011

1100 CET: UN’s weather agency says Japanese winds are dispersing radioactive material over the ocean, and there is no danger for Japan or the region for now.

Tohoku Electric will introduce electricity “rationing” with rotating blackouts starting from Wednesday.

TEPCO has come in for strong criticism from the PM’s office for being slow with information.

Kan strongly ordered the company not to withdraw its employees from the power plant, which has been facing a series of problems since Friday’s massive quake, ranging from explosions to radiation leaks.

”In the event of withdrawal from there, I’m 100 percent certain that the company will collapse,” Kan said. ”I want you all to be determined.”

The government, as well as the public, has been dissatisfied with the company’s way of releasing information regarding the crippled nuclear plant.

A man in his twenties and a 74 year old woman were rescued from under debris today – 4 days after the quake.

0930: Kyodo News – Water at spent fuel pools (which reactor? #4, #5 or #6?) may be boiling reducing the water in the pool. Cooling water is to be pumped in.

Is this also what happened at reactor#4? Reactors #4, 5 and 6 were not in operation when the quake and tsunami hit. There seem to be two categories of problems –

  1. at the operating reactors #1, 2 and 3 which all shut down automatically but where lack of cooling caused by a blackout of emergency power by the tsunami wave then led to uncovering of fuel rods and which in turn led to hydrogen explosions, and
  2. at the non-operating reactors #4, 5 and 6 where cooling to the spent fuel pools were compromised also due to loss of emergency power after the tsunami wave. At reactor #4, this somehow led to a fire during which a surge of  radiation leakage occurred. Temperatures are also rising in the spent fuel pools of reactors #5 and 6.

0830 CET: Nuclear designer states that the problem was a station blackout due to the high tsunami and loss of power to the cooling systems.

Press Conference by Chief Cabinet Secretary Edano.

Radiation at the plant perimeter was down to 595 μS at 3.30pm local time which is much higher than normal but not dangerous. For a period in the morning at around 0930 local time it was at the 11,000μS level which in one hour is equivalent to a lifetime dose. Radiation levels are worrying but they are decreasing and we are hopeful. The PM’s instructions to evacuate from the 20 km zone and to stay stay indoors for people in the 30 km zero was a matter of law. The fire at reactor #4 started at 0930 and is now out. This may have caused the radiation surge. Reactor #4 was not in operation but being refuelled(?). Reactor #2 is still being cooled and the rods are thought to be under water now so that the cooling seems to be functioning. Cooling for #1 and #3 continues stable. Temperatures have also risen at #5 and #6 gradually because after the tsunami the power to the cooling is not functioning properly and this is being watched closely and additional measures are being taken. Reactors #4, 5 and 6 were not in operation but some cooling is still necessary for the spent fuel pool. The radiation release after the fire at reactor #4 was probably from the spent fuel pool(?).

Small temperature rise has been observed at spent fuel pool at Fukushima reactors #5 and #6 which were not in operation and is being watched but no cooling has been needed to be applied so far.

0730 CET: The crisis around the Fukushima nuclear plant is diverting attention from the over 300,000 evacuees and the search and rescue efforts. Wintry weather is making things worse for all those displaced.

0700 CET Status:

Reactor No.2 at Fukushima Dai-ichi  has also suffered an explosion, the third reactor to do so. The containment vessel may be damaged. Some of the fuel rods are still exposed.

A fire at reactor no.4 broke out at 0938 local time and has now been put out. The roof of the building of reactor no.4 was damaged. A surge  of radiation leakage may have coincided with the fire.

Radiation levels dangerous to health were measured at the plant perimeter for short times.

Raised levels are measurable in the wind path which is towards Tokyo currently.

People within  the 20 – 30 km radius  are told to stay indoors. All within the 20 km zone are subject to an evacuation order.

A no-fly zone has been established in a 30 km radius zone around the plant.

NHK is broadcasting advice on precautionary measures for individuals when they are being advised to stay indoors.

Cooling efforts for reactors #1 to 3 are continuing.

IAEA believes the reactor containment vessels themselves are undamaged.

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