Day fifteen after the tsunami

Update 15:00(UTC)/16:00(CET)/00:00(JST)

NISA has released their update, link 1, link 2, link 3. I have also reattached the earlier JAIF figures at the bottom of the last update to see if it will fix the bug that gives an error when one clicks on the pictures.

As usual the NISA figures are between (). The NISA data is 3 hours older than the JAIF data.

 

Reactor 1:
Water level in the core: 1.65(1.65)  meters below the top of fuel assemblies
Flow rate of injected water: 7.2 cubic meters per hour
Core pressure: 476 (477) kPa
Containment pressure: 270 (270) kPa *note, in the last update I misstakenly wrote 370 kPa as containment pressure.
Core temperature(feedwater nozzle): 195.3 Celsius
Core temperature(bottom head) 146.3 Celsius
Dose rate within containment: 35.1 Sv/hour

Reactor 2:
Water level in the core: 1.1 (1.1)  meters below the top of fuel assemblies
Flow rate of injected water: 18.6 cubic meters per hour
Core pressure: unknown
Containment pressure: 116 (115) kPa
Core temperature(feedwater nozzle): 107 Celcius
Core temperature(bottom head): 100 Celsius
Dose rate within containment:  43.4 Sv/hour
Spent fuel pool temperature:  57 Celsius

Reactor 3:
Water level in the core: 2.3  meters below the top of fuel assemblies
Flow rate of injected water: 14.5 cubic meters per hour
Core pressure: 139 (139) kPa *note, I wrote the wrong pressure in the last update
Containment pressure: 106.6 (106.6) kPa
Core temperature(feedwater nozzle): 37.6 Celsius (sounds like an error on equipment)
Core temperature(bottom head): 106.1 Celsius
Dose rate within containment:  36.1 Sv/hour

Due to my error with containment pressure in the last update I withdraw my speculation that its hard to control the pressure in number 1. Rather it seems like the situation is fairly stable. Otherwise not much new information.

The US Department of Energy has done some arial surveys around Fukushima Daiichi and released the data. I have one pictures from it below(hats of to http://neutroneconomy.blogspot.com/ where I found the pictures). The dose rate unit used on the picture is millirad. 1 millirad=10 microgray =* 10 microsievert
*that equality between gray and sievert is only valid for gamma radiation. Gray measures the energy deposited while sievert is weighted in such a way that it expresses a cancer risk.  For gamma the weighting factor is 1.

Update 12:00(UTC)/13:00(CET)/21:00(JST)

No NISA updates have been released yet today, JAIF has released their update as usual(one hour old as of writing this).

Reactor 1:
Water level in the core: 1.65  meters below the top of fuel assemblies
Core pressure: 476 kPa
Containment pressure: 370 kPa
Core temperature(feedwater nozzle): no new data
Core temperature(bottom head) no new data
Dose rate within containment:  no new data

Reactor 2:
Water level in the core: 1.1  meters below the top of fuel assemblies
Core pressure: unknown
Containment pressure: 116 kPa
Core temperature(feedwater nozzle): no new data
Core temperature(bottom head) no new data
Dose rate within containment:  no new data

Reactor 3:
Water level in the core: 2.3  meters below the top of fuel assemblies
Core pressure: 202 kPa
Containment pressure: 106.6 kPa
Core temperature(feedwater nozzle): no new data
Core temperature(bottom head) no new data
Dose rate within containment:  no new data

All 3 reactors are now cooled with freshwater instead of sea water. It seems hard for them to get the pressure in the number one reactor under complete control. In JAIF's written update they say lights are on in all control rooms now. Levels of radioactive materials in the seawater around the plant is climbing. TEPCO is releasing updates on activity in both sea and air, I have attached levels as pictures in the bottom of this update.

The ground deposits of I-131 the prefectures around Fukushima ranges from less than 1 to 16 kBq per square meter. The cesium ground deposits ranges from less than 0.1 to 1.9 kBq per square meter(here are the last 3 MEXT updates on ground deposts link 1link 2link 3). The data form the worst effected prefectures are however omitted, we hope MEXT will make those figures available asap! As a comparison the ground deposits of cesium due to Chernobyl ranged from a couple of hundreds to a couple of thousand kBq per square meter.

 

Update, March 26, 12:00 (UTC) / 13:00 (CET) / 21:00 (JST)

Not much to add today. The radiation levels in the sea outside Fukushima I are sky-high. The long term effects are hard to predict now since a sea contamination is entirly different from a land contamination, where land is basicly a 2D area, which leads to a thin and high concentration on the surface, and where rains soon concentrate the contamination to "hotspots".  The sea on the other hand is a 3D volume where currents quickly dilute any contaminant by dispersing them over very wide areas.

The JAIF updates from 10:00, 16:00 and 21:00 (JST) for March 26 are pretty much uniform. The big news is that freshwater injection to the cores of 1, 2 and 3 has started as opposed to using salty sea water. Apart from that nothing new. The radiation readings at the main gate (1 km out) has stayed at 170 μSv/h all day. The west gate read 147 μSv/h at 13:30.

NISA has not said anything new since last night.

 

Links(english):
BBC We should stop running away from radiation
Hufftington post US brings fresh water to japan nuclear plant
NY Times Japan presses nuclear plant repair as more damage is found
Rod Adams Shaken, flooded, stressed by power outages, Fukushima Daiichi moves into second place
The Independent Fear and devastation on the road to Japan's nuclear disaster zone

Links(swedish):
Röda berget
Dr Angels blog
DN Radioaktivt jod tusen gånger tillåten nivå i havet
Aftonbladet Strålningen ökar runt Fukushima
SvD Radioaktivt vatten i reaktorer
Tänkvärt? Eller inte!
Grön horizont