This post is from April 2011. Facts and links may have changed since. See more from that month

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FEPC Info Sheet 4/5

I have nothing clever to say.  The full-text of the latest FEPC Info Sheet is after the jump.

Update to Information Sheet Regarding the Tohoku Earthquake

The Federation of Electric Power Companies of Japan (FEPC) Washington DC Office

As of 11:30AM (EST), April 5, 2011

  • Radiation Levels

o      The concentration of radioactive nuclides from the seawater sampled at the screen device (installed to remove waste before the intake of seawater) of Unit 2 of Fukushima Daiichi Nuclear Station was as follows:

The details of this report are available at:

http://www.tepco.co.jp/en/press/corp-com/release/11040506-e.html

 

Nuclides

(half-life)

Concentration (Unit : Bq/cm3)
Sampled at 11:50AM on April 2 Sampled at 6:25PM on April 3 Sampled at 9:00AM on April 4 Maximum Permissible Water Concentration
I-131

(8 days)

3.0 x 105 7.9 x 104 2.0 x 105 4.0 x 10-2
Cs-134

(2 years)

1.2 x 105 3.5 x 104 9.6 x 104 6.0 x 10-2
Cs-137

(30 years)

1.2 x 105 3.6 x 104 9.6 x 104 9.0 x 10-2

 

o      At 6:00PM on April 5, radiation level at main gate (approximately 3,281 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 112 micro Sv/hour.

o      At 6:00PM on April 5, radiation level at west gate (approximately 3,609 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 67.4 micro Sv/hour.

o      Measurement results of environmental radioactivity level around Fukushima Nuclear Power Station announced at 7:00PM on April 5 are shown in the attached PDF file. English version is available at:    http://www.mext.go.jp/english/radioactivity_level/detail/1304082.htm

o      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

o      At 6:00AM on April 5, pressure inside the reactor core: 0.308MPa.

o      At 6:00AM on April 5, water level inside the reactor core: 1.7 meters below the top of the fuel rods.

o      At 6:00AM on April 5, pressure inside the primary containment vessel: 0.15MPaabs.

o      At 6:00AM on April 5, the temperature of the reactor vessel measured at the water supply nozzle: 452.3 degrees Fahrenheit.

o      At 7:20AM on April 5, the temperature directly above the spent fuel pool by thermography measurement: 64.4 degrees Fahrenheit.

o      At 7:20AM on April 5, the temperature directly above the primary containment vessel by thermography measurement: 78.8 degrees Fahrenheit.

o      As of 7:00PM on April 5, the injection of freshwater into the reactor core continues.

o      As of 7:00PM on April 5, preparation to recover and transfer the accumulated water at the turbine building continues.

  • Fukushima Daiichi Unit 2 reactor

o      At 6:00AM on April 5, pressure inside the reactor core: -0.018MPa.

o      At 6:00AM on April 5, water level inside the reactor core: 1.5 meters below the top of the fuel rods.

o      At 6:00AM on April 5, pressure inside the primary containment vessel: 0.10MPaabs.

o      At 6:00AM on April 5, the temperature of the reactor vessel measured at the water supply nozzle: 287.1 degrees Fahrenheit.

o      At 6:00AM on April 5, the temperature of the spent fuel pool: 159.8 degrees Fahrenheit.

o      At 7:20AM on April 5, the temperature directly above the second containment building by thermography measurement: 82.4 degrees Fahrenheit.

o      At 2:15PM on April 5, TEPCO announced that the tracer (white colored dye) was observed entering the ocean through a crack on the lateral surface of the pit (a vertical portion of an underground structure for housing electric cables) near the seawater intake.

o      At 3:07PM on April 5, TEPCO began injecting coagulator into the soil around the pit in an attempt to stop the discharge of water.

o      As of 7:00PM on April 5, the injection of freshwater into the reactor core continues.

o      As of 7:00PM on April 5, preparation to recover and transfer the accumulated water at the turbine building continues.

  • Fukushima Daiichi Unit 3 reactor

o      At 7:20AM on April 5, the temperature directly above the spent fuel pool by thermography measurement: 132.8 degrees Fahrenheit.

o      At 7:20AM on April 5, the temperature directly above the primary containment vessel by thermography measurement: 64.4 degrees Fahrenheit.

o      At 10:20AM on April 5, pressure inside the reactor core: 0.005MPa.

o      At 10:20AM on April 5, water level inside the reactor core: 1.85 meters below the top of the fuel rods.

o      At 10:20AM on April 5, pressure inside the primary containment vessel: 0.1071MPaabs.

o      At 10:20AM on April 5, the temperature of the reactor vessel measured at the water supply nozzle: 184.5 degrees Fahrenheit. (This figure is under investigation.)

o      As of 1:30PM on April 5, approximately 4,978 tons of water in total has been shot into the spent fuel storage pool.

o      As of 7:00PM on April 5, the injection of freshwater into the reactor core continues.

o      As of 7:00PM on April 5, preparation to recover and transfer the accumulated water at the turbine building continues.

  • Fukushima Daiichi Unit 4 reactor

o      At 7:20AM on April 5, the temperature directly above the spent fuel pool by thermography measurement: 122 degrees Fahrenheit.

o      At 5:35PM on April 5, TEPCO began to shoot freshwater aimed at the spent fuel pool, with a specialized vehicle normally used for pumping concrete, until 6:22PM.

  • Fukushima Daiichi Unit 5 reactor

o      At 1:00PM on April 5, the temperature of the spent fuel pool: 94.6 degrees Fahrenheit.

  • Fukushima Daiichi Unit 6 reactor

o      At 1:00PM on April 5, the temperature of the spent fuel pool: 81.5 degrees Fahrenheit.

  • Fukushima Daiichi Common Spent Fuel Pool

o      At 7:10AM on April 5, the temperature of the spent fuel pool: 84.2 degrees Fahrenheit.

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)

Jeffrey Lewis

Writing on ACW 2004–2026

Dr. Jeffrey Lewis is the founding publisher of Arms Control Wonk.com. He is the Director of the East Asia Nonproliferation Program at the James Martin Center for Nonproliferation Studies at the Middlebury Institute of International Studies at Monterey. His also a non-resident affiliate at Stanford's Center for Security and International Cooperation and a Contributing Editor to Survival.

All posts by Jeffrey Lewis