ML12052A317
ML12052A317 | |
Person / Time | |
---|---|
Site: | North Anna |
Issue date: | 09/14/2011 |
From: | Roger Rihm NRC/EDO/AO |
To: | Martin R, Gerald Mccoy Plant Licensing Branch II, NRC/RGN-II/DRP/RPB5 |
References | |
FOIA/PA-2011-0357 | |
Download: ML12052A317 (5) | |
Text
Boyleý Patrick From: Rihm, Roger d.v Sent: Wednesday, September 14, 2011 1:42 PM To: Martin, Robert; McCoy, Gerald Cc: Kulesa, Gloria; Boyle, Patrick; OBrien, Margaret; Williamson, Edward; Howe, Allen; Hiland, Patrick; Khanna, Meena
Subject:
RE: Per my voice mail message Thanks. Regarding your comment in red, I was saying that based on Dominion's slide #46. Perhaps I could say INITIAL analysis. Regarding the one-pager, the congressman has requested any analysis and it is entitled "as of August 24," so doesn't claim to be current. I'm not sure we have much of a leg to stand on for not providing it to him.
I had sent this off to Gerry McCoy earlier today.
From: Martin, Robert Sent: Wednesday, September 14, 2011 1:32 PM To: McCoy, Gerald Cc: Kulesa, Gloria; Boyle, Patrick; Rihm, Roger; OBrien, Margaret; Williamson, Edward; Howe, Allen; Hiland, Patrick; Khanna, Meena
Subject:
FW: Per my voice mail message Importance: High Gerry, any comments on the Markey response?
Roger, the current facility operating license is issued to Virginia Electric and Power Company. Dominion is said to be a parent company. Based on what is on the license, I suggest referring to VEPCO as the licensee.
First paragraph: Is it true that collection and analysis of seismic data is complete? Collection may be complete but I'm reasonably sure that there is much analysis ahead of us by NRC staff of the seismic data.
Last paragraph: I suggest "... demonstrates to the NRC an acceptable basis for operation." There is some view within OGC that the Part 100, Appendix A words cited in the current version of the reply may only apply as a reactor siting criterion and not to operation. For now, I would simplify it to the above words. I presume this letter will go through OGC before issuance.
I would not recommend releasing the 1-pager to Congress. It contains many acronyms that aren't spelled out.
I believe it contains some outdated information. And it contains a lot of information that needs to be expanded in order to be intelligible to stakeholders outside the NRC.
From: Rihm, Roger Sent: Wednesday, September 14, 2011 8:58 AM To: Khanna, Meena; Martin, Robert
Subject:
FW: Per my voice mail message Importance: High FYI, I've been working with Kamal on this, but it occurred to me that perhaps you two should have a chance to look at this. Ifyou have comments, please discuss with Kamal/Pat and provide me with one NRR-approved version. Thanks.
From: Manoly, Kamal Sent: Tuesday, Septerhber 13, 2011 11:16 AM To: Hiland, Patrick Cc: Rihm, Roger Lýzý,-
-7
Subject:
FW: Per my voice mail message Importance: High
- Pat, I gave input to Roger Rihm to respond to congressman Markey and am very comfortable with the response. He likes to receive your okay as well. Please let him know.
Kamal From: Rihm, Roger Sent: Tuesday, September 13, 2011 9:24 AM To: Manoly, Kamal
Subject:
Per my voice mail message Importance: High Here is the revised draft letter. Can I get any comments and Pat's OK in the next day or so?
Cliff just sent me his enclosure and indicates in his email that he thinks I should get Pat's OK on that too. I've also attached Cliff's email. Please pursue that with Pat as well.
2
Boyle, Patrick From: Munson, Clifford Sent: Tuesday, September 13, 2011 9:19 AM To: Rihm, Roger Cc: Hiland, Patrick; Grobe, Jack; Flanders, Scott; Wilson, George; Khanna, Meena; Manoly, Kamal
Subject:
1 Pager for Chairman Jaczko on North Anna Earthquake Issue updated 9-1-1 l.docx Attachments: 1 Pager for Chairman Jaczko on North Anna Earthquake Issue updated 9-1-11 .docx You may want to check with NRR management to see if it is ok to release this -I would feel more comfortable after getting the ok from Jack Grobe and Pat Hiland.
Cliff 1
Summary of Earthquake Information for the North Anna NPP as of August 24, 2011 The North Anna Nuclear Power Plant (NANPP) has two Safe Shutdown Earthquake (SSE) ground motions, one for structures, systems, and components (SSCs) located on top of rock, which is anchored at 0.12 g, and the other is for SSCs located on top of soil, which is anchored at 0.18 g. The NANPP has two corresponding Operating Basis Earthquake (OBE) ground motion spectra, anchored at 0.09 g for soil and 0.06 g for rock. The figure below shows a comparison between the SSE and OBE for Units 1 and 2, the Unit 3 Combined License (COL) application Ground Motion Response Spectrum (GMRS), the current best estimate of the August 24, 2011 earthquake ground motions from the USGS (ShakeCast version 7), and predicted median and standard deviation earthquake motions using the EPRI ground motion prediction equations. The IPEEE review ground motion (not shown) was anchored at 0.16 g with a similar spectrum as the SSE.
The recent earthquake occurred at a close distance (18 kin) to the plant with a magnitude of 5.8 at a relatively shallow depth (6 kin). USGS estimates of the maximum ground motion at the plant evolved as new data become available. The current best estimate of the Peak Ground Acceleration (PGA) for the NANPP site is 0.26g, which contains uncertainty and may be updated later. This estimate indicates that the ground motion likely exceeded the SSE response spectra for NANPP Units 1 and 2 (0.12g) over a considerable frequency range, as shown by the green and red points in the figure. The estimated ground motion from the earthquake was not a surprise based on the combined operating license application (COLA) ground motion response spectrum for NANPP Unit 3. This preliminary estimate appears to validate the NRC's current seismic hazard assessment approaches and models for new reactors, as well as the basis for GI-199 reviews.
The USGS ground motion estimate values for the plant site are developed based on two types of input. The principal input is from using ground motion prediction equations (also called attenuation relationships) that were specifically developed for the Central and Eastern United States. This prediction ground motion is then modified based on intensity information that comes from the USGS "Did You Feel It?" (DYFI) system. The DYFI system is a method for using large numbers of inputs from affected persons to develop intensity maps that are used as a "ground truth." Currently, the USGS has received nearly 123,000 submitted reports.
NRC staff performed an independent analysis using the best estimate of the earthquake location and magnitude together with the EPRI ground motion prediction equations. The median and +/-1 standard deviation curves are shown. It can be seen that the 8 4 th percentile ground motions calculated by the staff are close to the USGS predictions. This makes sense because the USGS theoretical values were increased due to the intensity information that came out of the DYFI system.
Currently, the licensee is retrieving its seismic instrumentation recordings from within the plant and processing the information. However, we do not yet know the type and quality of the recording data that will be available to the NRC. Information from the NANPP will be used to evaluate the USGS estimates of ground motion and will be compared against the FSAR design basis. The data will be used to inform the staff whether additional analysis is needed.
The licensee has indicated that it will perform plant walk downs in accordance with RG 1.167, "Restart of a Nuclear Power Plant Shutdown by a Seismic Event," which endorses EPRI's "Guidelines for Nuclear Plant Response to an Earthquake" with conditions. If the SSE is
exceeded at certain frequencies, the staff will assess the licensee's evaluation of SSCs that are most sensitive to ground motion in that frequency band.
2.0 NA Unit 1&2 Rock SSE (Newmark at 0.12g)
NA Unit 3 COL GMRS c-j 1.5-0 USGS (ShakeCast Report Version 7) i- \
EPRI GMPE(2004, 2006) MW5.8 at 19km /
median and_+/-1 sd I
W / N 1.0- I QO /
Cn
/
/
/
I.
I.
/
CD, 0.5 -
0.0 F. - t -4 0.1 1 10 100 frequency (Hz)