[ RadSafe ] More on San Onofre - Engineer's input needed

Stewart Farber SAFarber at optonline.net
Sun Apr 8 15:21:16 CDT 2012

The two SG at San Onofre have about 10,000 individual tubes in total.
Depending on whether all tubes have a manufacturing defect and are likely to
keep failing regularly, I know in the past it was a routine procedure for a
plant to weld defective  SG tubes shut so that nothing from the primary side
can get carried over to the secondary loop. Back some time, Prairie Island
for example had to plug about 600 SG tubes and continued operations. It's a
question of how many tubes get welded shut and how much efficiency lost is
acceptable as a fraction of the approx. 5000 tubes in each SG.

I would think it all comes down to how many plugs are defective or are
likely to fail soon and can be repaired before the plant goes back on-line.
The grid operators, and regulatory agencies involved,  are likely to give
alternatives like welding defective tubes closed serious consideration when
they think about the consequences of a shortage of generating capacity by
taking San Onofre offline. 

Of course the NRC, may just torpedo the whole idea of SG repair and keep the
plant offline in their pursuit of what they state is the need for zero risk.
I guess operating old coal and gas plants with the significant environmental
and health effects to be realized with certainty is OK with zealous forces
against nuclear electric generation.

Stewart Farber
SAFarber at optonline.net

-----Original Message-----
From: radsafe-bounces at health.phys.iit.edu
[mailto:radsafe-bounces at health.phys.iit.edu] On Behalf Of Joel C.
Sent: Sunday, April 08, 2012 1:35 PM
To: radsafe at health.phys.iit.edu
Subject: [ RadSafe ] More on San Onofre - Engineer's input needed

It sounds like SCE spent $670 million on defective steam gennies.  I'd like
to hear from a knowledgable engineer about that.

Joel Cehn
joelc at alum.wpi.edu 
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