ML13066A328
| ML13066A328 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 04/08/2010 |
| From: | Galloway M Office of Nuclear Reactor Regulation |
| To: | Jeff Circle, Jeffrey Mitman Office of Nuclear Reactor Regulation |
| References | |
| FOIA/PA-2012-0325 | |
| Download: ML13066A328 (2) | |
Text
Mitman, Jeffrey From:
Galloway, Melanie \\
Sent:
Thursday, April 08, 2010 4:11 PM To:
Mitman, Jeffrey; Circle, Jeff Cc:
James, Lois
Subject:
RE: Status of the Delta Risk Comparison Analysis
- Jeff, I have no problem with your changes. The only thing that needs to be explained is the 1.5E-4--right now it has no context as the only value reflected in the text is the 2.0.
Mark had asked that the risk be reflected on a per modification basis. Was that able to be done to support the 10 am meeting?
Melanie From: Mitman, Jeffrey Sent: Thursday, April 08, '2 10 9:19 AM To: Galloway, Melanie; Circle, Jeff Cc: James, Lois
Subject:
RE: Status of the Delta Risk Comparison Analysis Melanie, my comments are below. I've also marked up you version of the draft to incorporate those comments.
Table 1 supplies the risk reduction from the proposed modifications. Thus the correct value for the risk reduction due to one possible modification to address the OFI is 1.5E-4 per year. The value of 2E-4 is the current risk level from the existing status quo. This modification will not eliminate the risk from a dam failure.
0 I recognize that this paper is addressing the risk reductions from the proposed modifications. However, there is another significant concern that I did not want ignored. This plant lacks the defense in depth required by our regulations. We can use the CCDF to illustrate that deficiency. However, even if Duke could prove (they can't) that the probability of failure of Jocassee is 2E-6 they would not meet the defense in depth requirements. Our 50.54(f) correspondence is perfectly aligned with this argument/concern. Duke has to have defense in depth and they need to have an acceptable CDF/LERF. They have neither. In my opinion, in our internal discussions we should make sure that NRC's concern is with both. We should not let this be characterized as only a risk issue. Hopefully, this concern comes through in the "additional considerations" discussion. I've tweaked this language a little.
Jeff From: Galloway, Melanie Sent: Thursday, April 08, 2010 6:32 AM To: Mitman, Jeffrey; Circle, Jeff Cc: James, Lois
Subject:
RE: Status of the Delta Risk Comparison Analysis Thanks, Jeff. I have softened the Issues discussion a bit and separated it into 3 paragraph and retitled it and added a sentence at the end of the last paragraph explaining that the other hazard's CCDPs will be less than 1 and thus their CCDF will be less than the values in the table. Review this sentence for accuracy.
1
I also didn't see why the flooding value in the table was 1.5 so I changed to 2.OE-4.
I will give this to Mark and let him know that you are looking first thing at my changes and will get back to him with any further mods to the writeup.
From: Mitman, Jeffrey Sent: Wednesday, April 07, 2010 5:29 PM To: Galloway, Melanie; Circle, Jeff Cc: James, Lois
Subject:
Status of the Delta Risk Comparison Analysis Attached is the subject description. It documents the conclusions, issues and status of the analysis.
Jeff 2