[Short entry] Proliferation of nuclear technology

Items of concern in today's NYT's article Taking a Risk With Nuclear Technology other then the obvious risks associated with proliferation of a power source which generates tons of waste, which cannot be disposed of for generations (isolation isn't disposal) include the issue related to "passive controls" that the Westinghouse reactors employ. These are control mechanisms usually associated with individual components of a reactor which respond without intervention from an electronic monitoring system and without intervention from a human operator. The response, obviously, of the component to an system imbalance which could tend to emergency is to reduce the possibility of that emergency. For example, a pressure-relief valve is a type of passive system. It requires no input from external control systems (electronic, human, or otherwise) to work. It simply responds in a threat-reduction manner by "the laws of physics."

There are several dangers associated with this notion. The most pronounced are based on the assumptions humans make in determining the behavior of the passive control. If the component, say the pressure-relief valve is faulty, "the laws of physics" will result in a different behavior of the valve.

Passive controls are also dangerous psychologically and socially because people (nuclear engineers, in particular) have been trained to believe that responses are likely to happen in certain ways. "Margin of error" factors are used to account for this, but these are only statistical measures.

Do you want finite, even if small, probabilities for a meltdown at the local reactor?