How much difference would it make to design a nuclear reactor’s containment vessel, which appears to be the last line of defense in a nuclear power plant’s malfunction, that would sit over a well at least 500ft. to a 1,000ft in depth? Wouldn’t that make it easier for a last resort effort such as dropping the vessel down a well to consider it sealed and, therefore, much safer for the World? Just one option…………
Interesting idea.
You’d have to design the well to avoid groundwater contamination. So basically you’d be trying to design a nuclear waste repository silo, then sitting the reactor on top.
It seems to be incredibly difficult politically to site these repositories, which is one reason why spent fuel is accumulating in cooling ponds instead of being shipped off to permanent storage.
The Fukushima designs are 40 years old and they did the best they could at the time, including detailed risk analysis. The risk of pond failure was estimated at 1/million reactor-years in an earthquake zone, allowing for personnel being distracted by an earthquake. Guess they didn’t figure in the tsunami.
Some later designs have an explicit concrete meltdown catcher, designed to dissipate heat by conduction but still inside the containment building.
January 23rd, 2012 at 1:00 am
Interesting idea.
You’d have to design the well to avoid groundwater contamination. So basically you’d be trying to design a nuclear waste repository silo, then sitting the reactor on top.
It seems to be incredibly difficult politically to site these repositories, which is one reason why spent fuel is accumulating in cooling ponds instead of being shipped off to permanent storage.
The Fukushima designs are 40 years old and they did the best they could at the time, including detailed risk analysis. The risk of pond failure was estimated at 1/million reactor-years in an earthquake zone, allowing for personnel being distracted by an earthquake. Guess they didn’t figure in the tsunami.
Some later designs have an explicit concrete meltdown catcher, designed to dissipate heat by conduction but still inside the containment building.
References :
something I read at nrc.gov
January 23rd, 2012 at 1:07 am
Absolutely, they sould ALL have been built underground but for a much simpler reason. It would have allowed natural circulation of cooling water by allowing hot water to rise and cooler water into the reactor. In a worst-case scenario, they simply could have been flooded.
Present designs REQUIRE circulation pumps which, in turn, require power. No power? Melt down.
Fail-safe design against non-fail-safe design. Duh?
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References :