Bobby's blog, Optimal Prediction, examines the Mystery of the Extra Xenon - 133 not accounted for by the known reactor meltdowns at Fukshima Daiichi.
The study being examined by Optimal Prediction is "The total release of xenon-133 from the Fukushima Dai-ichi nuclear power plant accident" by Andreas Stohl, Petra Seibert, & Gerhard Wotawa http://zardoz.nilu.no/~andreas/publications/222.pdf
Majia here: Analysis by Optimal Prediction suggests that the fuel inventory from Fukushima alone could not have been responsible for the entirety of the xenon detection.
A separate study that was available here http://www.batan.go.id/inge2011/file/day1/1650_mcintyre.pdf (now removed from the internet) found radioxenon levels in the Pacific Northwest 450,000X normal for over a month.
Here is the citation for this second study:
Justin McIntyre, Steve Biegalski, Ted Bowyer, Matt Copper, Paul Eslinger, Jim Hayes, Derek Haas, Harry Miley, J.P. Rishel, Vincent Woods “US Particulate and Xenon Measurements Made Following the Fukushima Reactor Accident. Available http://www.batan.go.id/inge2011/file/day1/1650_mcintyre.pdf. (These findings were also published in peer reviewed scientific journals -- see bottom of this post for citations).
Undoubtedly, Fukushima Daiichi was not the only power plant to suffer severe damage after the earthquake.
Indeed, this report (below) documents damaged plants, although it doesn't specify the range of damages:
Kenichi Ohmae (BBT University President) “Lessons of Fukushima Dai-ichi” (2011, October 28): Full report index available here: http://pr.bbt757.com/eng/. Full report here http://pr.bbt757.com/eng/pdf/finalrepo_111225.pdf. In Japanese available here: http://pr.bbt757.com/2011/1028.html. Appendix of conditions at various plants around Japan http://pr.bbt757.com/eng/pdf/apdx_chronology_and_power-loss.pdf
Enenews ran a headline of a press conference based on this report: Fukushima Report Introduced by Top Official Hosono: “Other reactors are all in considerably severe condition” — 14 total; Dai-ni, Onagawa, Tokai — “Extreme situations, though not much has been broadcast” (VIDEO) http://enenews.com/must-see-report-introduced-by-top-govt-official-hosono-actually-other-reactors-are-all-in-considerably-severe-condition-besides-fukushima-daiichi-14-reactors-total-dai-ni-onagawa-tokai
MAJIA HERE: I recently posted a list of early media reports of damage in Japan immediately after the earthquake
Previously I posted about reported damage at Tokai and explained why that location is particularly significant because of its role in processing plutonium
I don't know how many reactors melted down and I don't ever expect that information to be disclosed for it would reveal how vulnerable we are to these insanely dangerous complexes whose risks and costs far outweigh benefits.
•S. Biegalski, et al., US Particulate and Xenon Measurements Made Following the Fukushima Reactor Accident, accepted for publication in Jour. of Envir Radioactivity, 2011
•T. Bowyer, et al., Elevated Radioxenon Detected Remotely Following the Fukushima Nuclear Accident. Jour. of Envir. •Radioactivity 102 (7):681-687. doi:10.1016/j.jenvrad.2011.04.009
•P. Eslinger, et al., Source Term Estimation of Radioxenon Released from the Fukushima Daiichi Nuclear Reactors Using Measured Air Concentrations and Atmospheric Transport Modeling, to be submitted in Jour. of Envir. Radioactivity, 2011