ML030870298
| ML030870298 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 09/20/2002 |
| From: | Long S Office of Nuclear Reactor Regulation |
| To: | Horner D McGraw-Hill |
| References | |
| FOIA/PA-2003-0018 | |
| Download: ML030870298 (3) | |
Text
SSteven Long - Re: 2nd attempt at getting it right
' - ri el1 From:
To:
Date:
Subject:
Steven Long ta danielhorner@platts corn 9/20/02 10.18AM Re: 2nd attempt at getting it right
- Dan, Officially, I'm a "senior reliability and risk analyst" but you can call me "risk analyst" for short.
Steve
>>> <danielhorner@platts com> 09/20/02 09:55AM >>>
Thanks, Steve.
Todd Schneider is FENOC's spokesman. I'll readily admit to not knowing enough to have pressed him on it, but I believe what's in the story is pretty much exactly (and all) what he said If it's a confused or bogus explanation, I'll want to pursue that, once we finish putting this issue to bed.
Also, one more small item. I could have sworn we talked about what title to use for you, but I couldn't find it in my notes Can you give it to me again7 Thanks for everything. Until next time, DH "I "Steven Long" <SML@nrc.gdv> on 09/20/2002 08:19"17 AM To:
Daniel Horner/ST/FIS@FIS cc:
Subject. Re: 2nd attempt at getting it right
- Dan, tI4(
Page 2 q i 'nn
- Rp 9nrl ttmnt t aettina it riaht What you wrote about the cracking rates is accurate I'm a little mystified by the preceding paragraph, particularly the quote from "Schneider." I don't know who he Is, but the statement attributed to him seems to be confused. There are TWO sets of cracks that were discovered. One set is on top, about the middle of the exposed stainless steel clad area That area is was NOT dye penetrant tested on-site, to the best of my knowledge The second set of cracks in on the bottom surface of the Alloy 600 weld material that connected the clad (and the low alloy steel above it) to the Alloy 600 nozzle, forming part of the inner surface of the reactor head THAT is the area that Framatome thought was dye penetrant tested on-site. If it was tested, the question is why weren't the cracks found by that test? That same area around nozzles in other plants is being tested by dye penetrant to check for cracks that would need to be repaired before the plants return to power operation We want to know if that test failed to detect cracks around nozzle 3 at Davis-Besse because a detection failure could have implications for the adequacy of the past and future inspection done at other plants. Schneider's quoted statement that the test was done but it was from underneath indicates that the area of Alloy 600 weld material with the cracks WAS tested, which is imortant to us But, the rest of the quote about the cracks being on top seems to inidcate that Schneider (or your) don't understand the issue clearly enough to be a reliable source of info for us on exactly what was tested Steve
\\>>> <daniel horner@platts com> 09120/02 12:30AM >>>
- Steve, By time you get this, the issue already will be laid out And so if you e-mail it (rather than faxing or phoning), please indicate clearly where your changes are.
Many thanks, DH According to the report, dated Sept 7, "'It is believed that this weld area was dye penetrant tested under Work Order 02-001917-000, step 13, while on site.
This [condtion report] should determine whether this test was actually performed and if so, why it did not detect the crack indication." Schneider said the test had been conducted, but since it was from underneath, it did not detect the crack on top.
Steve Long of NRC's Office of Nuclear Reactor Regulation (NRR) said an important question raised by the finding concerns the "'heat," or batch, of alloy used in nozzle 3. The batch number of this heat is known, but the cracking rate of the batch is not known, he said If it turned out that that the crack rate was significantly better than that of some other measured batches, there would be potential concerns about the likelihood of cracking in other reactors. If, on the other hand, the crack rate of the batch from which the Davis-Besse nozzle came proved to be significantly worse than the worst known batches, there would be questions about how well the data describe-or bound-the reactors now in service.
Qtavion I nn - Re: 2nd atte nt at getting it rioht I
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.StevenLong Re: 2nd attempt at getting it right PPage 3 The third possibility, he said is that the cracking rate of the Davis-Besse nozzle's batch would be "about as bad" as the rate in the worst previously known batch. That would be somewhat -reassuring." he said, since such an outcome would not call into question the laboratory data.
Daniel Homer McGraw-Hill Nuclear Publications Phone. 202 383-2164 Fax-202 383-2125 eMail daniel horneraplatts com