Update: Detailed graphical status report on each reactor unit is available. Here is the picture for Unit 2 — click on the figure to access the PDF for all units.

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Yes, it really has been that long. So what happened during those 10+ days? For a long answer, look back over the daily posts on this blog, which also has plenty of links to more off-site information. For the short-hand version, I offer you this excellent graphic produced by the Wall Street Journal:

Things continue to develop slowly, but I think now towards an inevitable conclusion — barring any sudden turn of events, a cold shutdown (reactor temperature below 100C) should be achieved in units 1 to 3 within the next week (or two?). The other priority is to get the spent fuel storage sufficiently covered with water to make them approachable (and ideally to get AC power systems restored to these ponds, as has been the case already for units 5 and 6). The clean up, diagnostics, and ultimate decommissioning of Fukushima Daiichi, of course, will take months and years to complete.

What is the latest news?

First, there is a new estimate of the tsunami damage. According to the NEI:

TEPCO believes the tsunami that inundated the Fukushima Daiichi site was 14 meters high, the network said. The design basis tsunami for the site was 5.7 meters, and the reactors and backup power sources were located 10 to 13 meters above sea level. The company reported that the maximum earthquake for which the Fukushima Daiichi plants were designed was magnitude 8. The quake that struck March 11 was magnitude 9.

Second, the IAEA reports elevated levels of radioactivity in the sea water off the coast of these reactors. That is hardly surprising, given that contaminated cooling water would gradually drain off the site — and remember, it is very easy with modern instruments to detect radioactivity in even trace amounts. These reported amounts (see table) are clearly significantly elevated around the plant — but the ocean is rather large, and so the principle of disperse and dilute also applies.

I’m reminded of a quote from James Lovelock in “The Vanishing Face of Gaia” (2008):

In July 2007 an earthquake in Japan shook a nuclear power station enough to cause an automatic shutdown ; the quake was of sufficient severity-over six on the Richter scale-to cause significant structural damage in an average town. The only “nuclear” consequence was the fall of a barrell from a stack of low-level waste that allowed the leak of about 90,000 becquerels of radioactivity. This made front page news in Australia, where it was said that the leak posed a radiation threat to the Sea of Japan.The truth is that about 90,000 becquerels is just twice the amount of natural radioactivity, mostly in the form of potassium, which you and I carry in our bodies. In other words, if we accept this hysterical conclusion, two swimmers in the Sea of Japan would make a radiation threat.

For further details on radiation trends in Japan, read this from WNN. In short, levels are hovering at or just above background levels in most surrounding prefectures, but are elevated in some parts of Fukushima. However, the World Health Organisation:

… backed the Japanese authorities, saying “These recommendations are in line with those based on accepted public health expertise.”

Below is a detailed situation summary of the Fukushima Daiichi site, passed to me by a colleague:

(1) Radioactivity was detected in the sea close to Fukushima-Daiichi. On March 21, TEPCO detected radioactivity in the nearby sea at Fukushima-Daiichi nuclear power station (NPS). TEPCO notified this measurement result to NISA and Fukushima prefecture. TEPCO continues sampling survey at Fukushima-Daiichi NPS, and also at Fukushima-Daini NPS in order to evaluate diffusion from the Fukushima-Daiichi. Though people do not drink seawater directly, TEPCO thinks it important to see how far these radioactivity spread in the sea to assess impact to human body.



Normal values of radioactivity are mostly below detection level, except for tritium. (detection level of Co-60 is 0.02Bq/ml) Also, samples of soil in the station have been sent to JAEA (Japan Atomic Energy Agency).

(2) Seawater injection to the spent fuel pool at Fukushima-Daiichi unit 2. This continues, with seawater injected through Fuel Pool Cooling and Cleanup System (FPC) piping. A temporary tank filled with seawater was connected to FPC, and a pump truck send seawater to the tank, then fire engine pump was used to inject seawater to the pool. Although the water level in the pool is not confirmed, judging from the total amount of injected seawater, 40 tons, it is assumed that the level increased about 30 cm after this operation.

(3) Brown smoke was observed from unit 3 reactor building. At around 3:55 pm on March 21, a TEPCO employee confirmed light gray smoke arising from the southeast side of the rooftop of the Unit 3 building. Workers were told to evacuate. It is observed the smoke has decreased and died out at 6:02pm. TEPCO continues to monitor the site’s immediate surroundings. There was no work and no explosive sound at the time of discovery.

(4) Smoke from unit 2 reactor building (as of 9:00pm, March 21). TEPCO’s unit operator found new smoke spewing from mountain side of unit 2 reactor building around 6:20 pm, which was different smoke from blow-out panel on the sea side. There was no explosive sound heard at the time. At 7:10 pm, TEPCO instructed workers at unit 1 – 4 to evacuate into the building. Evacuation was confirmed at 8:30 pm.

(Note: Since there was another smoke found from unit 3 at 1:55pm and evacuation was completed at that time, no workers were remained at the units when smoke found at unit 2.)

TEPCO assumes the smoke is something like vapor, but are still investigating the cause of this smoke with monitoring plant parameters.

Radiation level near the Gate of Fukushima-Daiichi NPS increased at the time of smoke, then decreased to prior level.

5:40 pm 494 μSv/hr

6:10 pm 1,256 μSv/hr

6:20 pm 1,428 μSv/hr

6:30 pm 1,932 μSv/hr

8:00 pm 493.5 μSv/hr

As a result of smoke from unit 2 and 3, scheduled water cannon spraying operations for March 21 were postponed.

(5) Power supply restoration at unit 2 (as of 5:00 pm, March 21). Power cables have been connected to the main power center (existing plant equipment) and confirmed as properly functioning. Presently, soundness tests of the equipment are underway. A pump motor, which is used to inject water to spent fuel pool, has been identified as needing to be replaced.

Similar power connections have been made to reactors 5 and 6 and a diesel generator is providing power to a cooling pump for the used fuel pools. Power cable is being laid to reactor 4, and power is expected to be restored to reactors 3 and 4 by Tuesday.

Kyodo News now reports that all 6 units are connected to external power, and control room power and lighting is about to be restored.

The water-spraying mission for the No. 4 reactor, meanwhile, was joined by trucks with a concrete squeeze pump and a 50-meter arm confirmed to be capable of pouring water from a higher point after trial runs.

With the new pump trucks arriving, the pumping rates for water spraying has increased to 160 tonnes per hour through a 58 metre flexible boom via remote control.

Here is the latest FEPC status report:

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Radiation Levels At 04:30PM (JST) on March 21, radiation level outside main office building (approximately 1,640 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 2,015 micro Sv/hour. At 06:30PM on March 21, radiation level at main gate (approximately 3,281 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 1,932 micro Sv/hour. Measurement results of ambient dose rate around Fukushima Nuclear Power Station announced at 1:00PM and 4:00PM on March 21 are shown in the attached two PDF files respectively. For comparison, a human receives 2,400 micro Sv per year from natural radiation in the form of sunlight, radon, and other sources. One chest CT scan generates 6,900 micro Sv per scan.

Fukushima Daiichi Unit 1 reactor At 2:25PM on March 21, pressure inside the reactor core: 0.198MPa. At 2:25PM on March 21, water level inside the reactor core: 1.75 meters below the top of the fuel rods. At 2:25PM on March 21, pressure inside the primary containment vessel: 0.16MPaabs. As of 4:00PM on March 21, the injection of seawater into the reactor core continues. As of 7:00PM on March 21, external power generation is connected and the functionality of the electric devices is being checked.

Fukushima Daiichi Unit 2 reactor At 2:25PM on March 21, pressure inside the reactor core: -0.023MPa. At 2:25PM on March 21, water level inside the reactor core: 1.35 meters below the top of the fuel rods. At 2:25PM on March 21, pressure inside the primary containment vessel: 0.12MPaabs. At 2:25PM on March 21, the temperature of the spent fuel pool: 122.0 degrees Fahrenheit. At 6:22PM on March 21, steam was emitted from the secondary containment building. (Under investigation) As of 4:00PM on March 21, the injection of seawater into the reactor core continues. As of 7:00PM on March 21, external power generation is connected and the functionality of the electric devices is being checked.

Fukushima Daiichi Unit 3 reactor At 9:30PM on March 20, the Tokyo Fire Department began to shoot water aimed at the spent fuel pool, continuously until 3:58AM on March 21 (roughly 1,137 tons in total). At 12:25PM on March 21, pressure inside the reactor core: -0.083MPa. At 12:25PM on March 21, water level inside the reactor core: 1.6 meters below the top of the fuel rods. At 12:25PM on March 21, pressure inside the primary containment vessel: 0.120MPaabs. At 3:55PM on March 21, gray smoke was emitted from the secondary containment building. At 4:49PM on March 21, the gray smoke changed to white smoke, but the volume of the smoke was unchanged. At 6:02PM on March 21, it was confirmed that the emission of smoke had ceased. As of 4:00PM on March 21, the injection of seawater into the reactor core continues. As of 7:00PM on March 20, about 3,742 tons of water in total has been shot to the spent fuel storage pool. As of 7:00PM on March 21, activities for connecting an external power supply are underway.

Fukushima Daiichi Unit 4 reactor At 6:22PM on March 20, 10 Self Defense Force vehicles began to shoot water aimed at the spent fuel pool, until 7:43PM (roughly 81 tons in total). At 6:37AM on March 21, 12 Self Defense Force vehicles and TEPCO began to shoot water aimed at the spent fuel pool, until 8:41AM (in total about 91 tons). TEPCO used one high pressure water cannon supplied by the US Army. As of 7:00PM on March 21, roughly 83 tons of water in total has been shot to the spent fuel storage pool. As of 7:00PM on March 21, activities for connecting an external power supply are underway.

Fukushima Daiichi Unit 5 reactor At 4:00PM on March 21, the temperature of the spent fuel pool: 108.1 degrees Fahrenheit. As of 7:00PM on March 21, external power generation is connected and the functionality of the electric devices is being checked.

Fukushima Daiichi Unit 6 reactor At 7:27PM on March 20: cold shutdown At 4:00PM on March 21, the temperature of the spent fuel pool: 96.8 degrees Fahrenheit. As of 7:00PM on March 21, external power generation is connected and the functionality of the electric devices is being checked.

Fukushima Daiichi Common Spent Fuel Pool From 10:37AM to 3:30PM on March 21, roughly 130 tons of water in total has been injected into the spent fuel storage pool.



Our official sources are:

Office of The Prime Minister of Japan

Nuclear and Industrial Safety Agency (NISA)

Tokyo Electric Power Company (TEPCO) Press Releases

Ministry of Education, Culture, Sports, Science and Technology (MEXT)

And, to wrap up this report, the the Japan Atomic Industrial Forum has provided their 19th reactor-by-reactor status update (19:00 March 22):

I’ll probably only do a detailed report once every few days now, as things are no longer changing quickly, and we have other issues to start exploring. There’s another reason too — I’m exhausted!