One important landmark in the process of dealing with the disastrous accident at the Fukushima No. 1 nuclear power plant has come into sight.
In the latest progress schedule for the work to bring the nuclear crisis under control, the government and Tokyo Electric Power Co., which operates the plant, clearly stated that the crippled reactors will be brought to a stable state known as “cold shutdown” by the end of the year.
But what exactly does cold shutdown mean?
Before the March 11 earthquake and tsunami, cold shutdown generally referred to a stable condition that is realized by shutting down, cooling the reactor and containing radiation when a potentially dangerous situation arises. But the reactors at the Fukushima plant are not in normal conditions.
It is likely that some of the fuel in the reactors has melted and their pressure vessels are damaged. It is impossible to gain accurate information about the conditions of the reactors as in normal times.
The current emergency situation where exposed nuclear fuel is presumably lying in damaged reactors is likely to continue.
Another cause for worry is continued aftershocks that rock various parts of eastern Japan from time to time. There are concerns about what kind of effect a major earthquake would have on the fuel inside the reactors.
There are still high hurdles to overcome before the government can safely declare the reactors to be in cold shutdown.
- Cold Shutdown by January? – Reactor Temperatures Still Trouble Workers At Fukushima Daiichi (enformable.com)
- Hosono pledges to achieve mysterious “cold shutdown” by year-end (enformable.com)
- NISA releases safety plan for Fukushima plant after cold shutdown – Concern that ‘Cold Shutdown’ Tepco Boasts is Temporary and Unstable (enformable.com)
- Japanese Reactor Research Educator – “What’s the point of cold shutdown now we know fuel is no longer sound?” (enformable.com)
- Expert urges checks of reactor interiors – TEPCO Should Ensure Cooling Methods Are Effective & No More Criticality In Fuel (enformable.com)
- Cold Shutdown: Facade of communication minimizing the disaster – Corium is the taboo word after Fukushima (enformable.com)
- All 6 Fukushima Daiichi Reactors and Fukushima Daini nuclear power plant’s likely to be decomissioned (enformable.com)
- Japanese Minister Hosono in charge of Fukushima asks United States and France to aid scrapping reactors (enformable.com)