[ RadSafe ] Re: Fw: Someone just responded to your comment

[Gv1 at aol.com]

I don't think the issue of reduced exposure is that work is being put off in 
a careless manner, it's more related to the fact that we are finally running 
power plants >97% capacity over the fuel cycle like we were supposed to.  What 
happened at Davis Besse was not driven by money, but by not interpreting the 
symptoms they were presented correctly and not digging deeper.  Had their 
motive truly been just about money, they clearly would have shut down to save the 
expensive reactor head and to prevent the plant for being down many months 
while a new head was created.

I believe the component and system surveillance requirements are the same as 
they have always been, but more time has been put into predictive maintenance 
templates.  As an example, when plants used to trip every 150 days or so, we 
used to go into components arbitrarily, not because there was a risk.  Now, the 
decision would be based upon the ultimate surveillance requirements and 
performance-based monitioring.

One thing that is interesting is that now that we're running these plants as 
long as were are supposed to, some components are having difficulty making it 
the full cycle.  This creates short-term increases in costs to replace 
components with more durable ones to make the entire cycle.

When looking at collective rad exposure it is also necessary to understand 
the plant design.  For example, Turkey Point is an older PWR with relatively few 
components to fail compared to some later model BWR units.  Remember in the 
70's when car makers went from the simple V-8 and carburetor to the smog 
engines with all of the "extra" stuff.  Those later, improved engines, actually had 
worse reliability and increased maintenance because of the greater number of 
components available for failure.  Now, both cars and power plants are being 
redesigned in a more efficienct manner instead of just adding additional 
components.  Newer designs have fewer overall components, so the overall mean time 
before failure should be longer.

The reduction in outage duration is driven purely by economic reasons such as 
the threat of being competetive with other energy sources in a deregulated 
environment.  This means the correct amount of maintenance has to be done to 
maximize reliability.  It has forced utilities to better understand what they do 
and why they do it.  Mods done to the plant to make more money are also the 
ones that increase reliability and safety.  This really has been a win-win 
situation for reducing collective rad exposure and utilities working to make 
nuclear power "too cheap to meter".

Glen Vickers
Nuclear Power