The Trojan experience with EDM was the same as San Onofre. Trojan used
EDM for an upflow modification requiring numerous 3" diameter holes in
the top core plate. The clean up system was woefully inadequate and we
had high activity corrision product hot particles for years after. The
clean up system is the most important. I recommend doing some mockup
testing of the clean up/filtration system to ensure it will actually
collect the debris.
Tom Meek
(Trojan RPM when it existed)
On 4/11/2012 8:23 AM, [email protected] wrote:
Hi Barbara, many, many moons ago, we (San Onofre) did EDM on the
fuel alignment plate. Not the same as your work on the alignment pins
but still EDM on highly activated material. The main thing I recall
was that in spite of all the efforts to ensure aggressive underwater
vacuuming for debris, there was significant material (discrete
particles) remaining on the cavity floor that presented contamination
control challenges when the work was complete and equipment was being
removed from the pool. And then again once drained down and
conducting final cavity cleaning. I don't recall any airborne issues
because the particles were "large." Hope that helps. Eric
Eric M. Goldin, CHP
Southern California Edison
<[email protected]>
From: BJ Thompson <[email protected]>
To: "[email protected]" <[email protected]>
Date: 04/10/2012 02:12 PM
Subject: Powernet: Underwater EDM on Primary Components (Quick Benchmark)
Sent by: [email protected]
------------------------------------------------------------------------
We are preparing to inspect and possible repair a bent alignment pin
on our Upper Internals package. Is there any OE you would like to
share on contamination controls, airborne radioactivity, high activity
particle generation, etc.
Thanks for your fast feedback!
Barbara J. Thompson
Supervisor of Exposure Control
Dominion - North Anna Power Station
Email: [email protected]_ <mailto:[email protected]>
Phone: 540-894-2605
Beeper: #3469
FAX: 540-894-2408
*CONFIDENTIALITY NOTICE:* This electronic message contains information
which may be legally confidential and/or privileged and does not in
any case represent a firm ENERGY COMMODITY bid or offer relating
thereto which binds the sender without an additional express written
confirmation to that effect. The information is intended solely for
the individual or entity named above and access by anyone else is
unauthorized. If you are not the intended recipient, any disclosure,
copying, distribution, or use of the contents of this information is
prohibited and may be unlawful. If you have received this electronic
transmission in error, please reply immediately to the sender that you
have received the message in error, and delete it. Thank you.
----------------------------------- Powernet - a service of the Health
Physics Society Power Reactor Section Powernet archives at
http://www.mail-archive.com/[email protected]/ Reply to:
[email protected] If Questions, contact Mike Russell, CHP at
[email protected]
