On Thursday, March 17, 2011 2:14:54 PM UTC-4, dpb wrote:
On 3/17/2011 9:28 AM, Eric S. Smith: Left-Field Marshal wrote:
On Wednesday, March 16, 2011 9:37:11 PM UTC-4, dpb wrote:

I prefer to look at the _OPERATING_ reactors and their collective
output.

In doing so, don't you risk cherry-picking, though?...

Not in realistically assessing risk, no, not really.

Those that have been decommissioned aren't going to be a future problem
since they're not in the population at risk.

This sidesteps an important assessment that someone outside of the industry in question is going to want to make, though: are these people as smart as they claim to be? In order to make *that* assessment, I think it's reasonable to look at past screw-ups. One might see an encouraging pattern of learning from mistakes; one might see the same damned error over and over again.

Of the existing population, all are similar vintage LWRs and virtually
every one has seen an improvement in overall availability and reduction
in events over the years.

"Availability" doesn't really tell us much about safety. Isn't that a bit like claiming that "Space shuttles aren't vulnerable to ice strikes; why, we've launched more this year than last year!"

Certainly continued vigilance is important and those in particularly
prone areas should evaluate their readiness and design basis events in
view of the current events but there's no reason to panic.

In view of current events, we're now painfully aware of various reactor designs' complete reliance on active removal of decay heat. Would nuke-boosters ever have brought this up of their own accord? "It scrams in seconds," the line goes, "and then the problem's over." One does not hear the implied caveat: "...as long as electrical power is reliably available for about a week afterward." There've been at least two epic regional blackouts in North America that I can think of, and anyone who works in IT has heard UPS horror stories. With that base so blatantly uncovered, one's skepticism is raised to what is, in retrospect, a more appropriate level.

--Eric Smith

On 3/17/2011 3:58 PM, Eric S. Smith: Left-Field Marshal wrote:
....

In view of current events, we're now painfully aware of various
reactor designs' complete reliance on active removal of decay heat.
Would nuke-boosters ever have brought this up of their own accord?...

If it weren't "brought up" to use your words, there wouldn't be decay
heat systems.

Read a FSAR sometime to see what (and how many) safety systems exist and
the level of redundancy and the design bases.

You'd be surprised I'd warrant...

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