271. FUKUSHIMA CRISIS: UNMONITORED RELEASES Preliminary Assessment of Accident Sequences and Potential Atmospheric Radiation Releases
- Author:
- David Albright, Paul Brannan, and Christina Walrond
- Publication Date:
- 03-2011
- Content Type:
- Special Report
- Institution:
- Institute for Science and International Security
- Abstract:
- instances of unmonitored radiation releases to the atmosphere from the Fukushima Daiichi nuclear reactors. The radiation readings and ground level wind directions are from the TEPCO web site. ISIS could not validate TEPCO’s information, but the data appear adequate to conduct some scoping analysis of the releases. Using this information, ISIS has sought to understand the fate of the releases and determine whether radiation monitoring stations intersected the plume of released radioactive material. We welcome any input. Since March 11, reactor units 1-4 at the Fukushima Daiichi nuclear plant have experienced hydrogen explosions, fires, partial melting of irradiated or “spent” fuel in the reactors, the uncovering and possible burning of irradiated fuel in spent fuel ponds at reactor 4 and perhaps other reactors. Table 1 lists several known accidents that occurred through March 18. These accidents, and perhaps ones that were not noticed or reported, released significant amounts of radiation into the atmosphere that the winds spread widely. They all require greater scrutiny. From an analysis of the limited data on atmospheric releases, ISIS has developed several key findings. The first is that the limited radiation detection capabilities at the Fukushima Daiichi plant following the earthquake and tsunami eliminated the ability to detect, characterize, or track a release of radiation. Many releases went partially or completely undetected by on-site monitoring. None of the releases from accidents were monitored as to their radioactive contents. Although the amount and type of radionuclides in these releases cannot be estimated from the existing on-site monitoring data, the existing data support that the potential for significant radiation doses to off-site population exists, particularly in sectors northwest and southwest of the reactors.
- Topic:
- Natural Disasters, Nuclear Power, Nuclear Safety, Disaster Management, Fukushima Disaster, and Earthquake
- Political Geography:
- Japan and Asia