Quote: (Originally Posted by
MarkZ)
Alex,
The incident at Three Mile Island was caused by a faulty valve leading to a series of events that up to that point in history was never seen before or anticipated. Regardless of the speculation after it happened not one person on earth provided input to anybody in any country as to the possibility beforehand. The most remarkable thing is beyond the incident it is probably the only major event in this country that was not followed by scores of conspiricy theories afterward. The greatest minds in the world felt these plants were as safe as they reasonably could be.
To add to this, Fermi I (my next door neighbor at the time was a physicist at the plant) nearly blew its stack as a consequence of a design change which was made
to guard against a potential failure that could have led to a failure of the containment under very unlikely, but possible, circumstances.
Unfortunately, that act of "anticipating" a potential risk and attempting to mitigate it (via these very same sorts of formal FMECA procedures)
introduced a second risk which was not anticipated, and what's worse, detecting that this second fault HAD occurred was missed due to an omission in the design that was ONLY significant with the first unanticipated risk in the system. NOBODY anticipated that second potential failure or its impact, and it was thus not modelled or controlled for.
The only reason this second fault was caught and disaster averted was the keen eye of a physicist on duty at the time who noted a reading that was out of the ordinary compared to what he had seen before. It was not a reading that was in and of itself dangerous, but he didn't understand what he was seeing. He initiated a scram.
Had he not done so
when he did Monroe to Detroit (including my home, natch) would have been blanketed in a nice covering of radioactivity, and it is very likely that I (along with a whole lot of other people) would not be here.
You think Chernobyl was bad? You have no idea.....