Summary of the Crisis
The earthquake on March 11, 2011, off the east coast of Honshu, Japan’s largest island, reportedly caused an automatic shutdown (called a “scram”) of eleven of Japan’s fifty-five operating nuclear power plants. Most of the shutdowns proceeded without incident. The plants closest to the epicenter, Fukushima and Onagawa, were damaged by the earthquake and resulting tsunami.
TEPCO immediately began to experience problems with the Daiichi units, as temperatures began to rise in the reactors. With the primary and secondary cooling systems for the Daiichi reactors offline, TEPCO began trying to cool the reactor cores with seawater. Boron6 has been added to the seawater to help slow down the nuclear reactions and cool down the reactor cores. Pressure began building in Daiichi reactor 1, resulting in an explosion on March 13, 2011, and radiation leak possibly from a build-up of hydrogen gas. Falling water levels in the reactor core are thought to have exposed fuel rods, leading to oxidation of the zirconium cladding resulting in the formation of hydrogen gas.
An explosion was reported at reactor 3 on March 14, 2011, with an associated release of radiation. At this time, while the containment structures at reactors 1 and 3 were breached, the reactor vessels themselves were thought to be undamaged. Falling water levels in reactor 2 and increasing pressure eventually led to another explosion on March 15, 2011, resulting in damage to the roof of the building above the reactor vessel and a release of radiation. It was unclear at that time whether the reactor vessel itself was damaged in the explosion. Fires were also reported at reactor 4, with the loss of water levels in the spent fuel pool. Elevated radiation levels measured around reactor 4 caused the temporary suspension of reactor control room operations on March 16, 2011. The spent fuel pool of reactor 3 was also reported to be boiling, with the reported release of radioactive steam. Water is also being introduced to the non-operational reactors 5 and 6 at the Daiichi station. The Japanese military may be enlisted to pump water into reactor 3 and the spent fuel pool in reactor 4.
- March 15th, 2011 – Congressional Research Service – Fukushima Nuclear Crisis (enformable.com)
- March 29th, 2011 – Has TEPCO-NISA determined extent of damage to floors around spent fuel pool? (enformable.com)
- March 30th, 2011 – Using Catawba and Browns Ferry MOX safety evaluation reports (enformable.com)
- March 14th, 2011 – Indications of Breach of Containment at Reactor 2 (enformable.com)
- March 15th, 2011 – DORL Looking at licensing actions with sensitivity to potential considerations from the ‘Japanese situation’ (enformable.com)
- April 2011 – Risk versus Concern – Public Health Messaging of the Fukushima Daiichi Nuclear Power Plant Incident (enformable.com)
- March 15th, 2011 – ANS Propaganda Marketing – Urgent Need For Media Contacts To Help Correct Inaccurate & Misleading News Reports (enformable.com)
- March 11th, 2011 – Fukushima Daini Information (enformable.com)
- March 15th, 2011 – Core Exposed at #2 Fukushima Daiichi (enformable.com)
- March 31st, 2011 – We may get inquiries after recent stories of radioactive traces in milk – direct to links (enformable.com)
- March 30th, 2011 – Do we have someone who can address technical comments? (enformable.com)
- March 23rd, 2011 – Regarding the NRC “Screening Process” – Never hurts to reinforce what’s already been stated (enformable.com)
- March 30th, 2011 – Now that you’ve returned from Japan, would you meet with us? (enformable.com)