Some links on the Fukushima Daiichi #1 crisis

(This post is being updated without warning)

Very developing news:

• Explosion heard in vicinity of one of the Fukushima NPPs [19]
• Concrete walls collapse at NPP; unclear which building [20]
• White smoke observered [21] (attached video is not of NPP)

(earlier content follows)

The biggest crisis supposedly involves Fukushima-Daiichi unit #1 [ref 1]. According to IAEA's CNPP database [ref 2], this is a General Electric BWR/3 reactor [table, ref 3] (refuting wikipedia [ref 4], which incorrectly thinks it is a BWR/4). Nuclear Tourist [ref 5] says this reactor uses a Mark I containment (pictured below). An NRC introduction I found, "Reactor Concepts Manual | Boiling Water Reactor (BWR) Systems" [ref 6], gives a basic overview of the coolant systems which are in the news (RCIC, ECCS). Some more information is in an article by Madgi Ragheb (UIUC) [ref. 7]

There are ongoing press releases from TEPCO with details [11].

Brave New Climate has a very active discussion thread [17]

Developing news:

• Fuel failure suspected as cesium (volatile fission product) detected outside [8] [9]
• Report that fuel rods were uncovered [10]; not corroborated
• Containment building vented to atmosphere at Fukushima Daiichi #1 [8]; limited radiological release
• Dose rate reached 1,000x background in control room (~65 μSv/hr), 8x background on-site outdoors (~0.5 μSv/hr) [14] (cf. radiation sources [15])
• Reports claim Fukushima Daini nos. 1,2,4 control room temperatures exceed 100 °C [8][9]; probable mistranslation -- TEPCO says pressure suppression chambers exceeded 100 °C at exactly these reactors [12]
• (in the Mark I containment systems, that means the large torus on the diagrams below. Not sure if these reactors have torii)
• Some primary coolant pumps flooded with seawater, nonfunctional [9]
• TEPCO reports trapped worker seriously injured [12]
• TEPCO reports worker overirradiated (106.3 mSv = 10.63 rem) [13] (this is harmful but not acutely fatal)
• TEPCO reports more worker injuries [13]: one broken bone, one unconscious, one with possible heart problem
• Almost 51,000 evacuated over 10 km radius [16]

GE Mark I BWR containment [Magdi Ragheb, U. Illinois at Urbana-Champaign]

GE Mark I BWR containment [NRC]

[1] [WSJ] Nuclear Plants Release Radiation

[2] [IAEA] Country Nuclear Power Profiles 2010

[3] [IAEA CNPP] Reactors in Operation, 31 Dec. 2009

[4] [Wikipedia] List of boiling water reactors

[5] [Nuclear Tourist] Containment

[6] [NRC] Reactor Concepts Manual | Boiling Water Reactor (BWR) Systems

[7] [M. Ragheb] Containment Structures

[8] [BusinessWeek] Japan Reactor Rods May Have Started to Melt, Agency Says

[9] [Mainichi Shimbun] Meltdown feared at Fukushima nuclear plant after quake

[10] [Nikkei] Possible Meltdown At Tepco Reactor

[11] [TEPCO] Press Releases

[12] [TEPCO] Plant Status of Fukushima Daini Nuclear Power Station (as of 1PM March 12th)

[13] [TEPCO] Plant Status of Fukushima Daiichi Nuclear Power Station (as of 1PM March 12th)

[14] [Washington Post] Japanese nuclear reactors in peril, radiation surges after earthquake, tsunami

[15] [ANS] Radiation Dose Chart

[16] [MSNBC] Japan braces for meltdown at nuclear plant

[17] [Brave New Climate] Discussion Thread – Japanese nuclear reactors and the 11 March 2011 earthquake

[18] [NYT] Radioactive Element Detected Near Nuclear Plant

[19] [CNN] Report: Explosion near Japanese nuclear plant

[20] [LA Times] Meltdown fears rise as walls crumble at Japan nuclear site

[21] [Telegraph] Japan earthquake: nuclear disaster feared after power plant 'explosion'