ML14034A050

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Summary of Audit Conducted 1/28-29/2014, License Amendment Request to Adopt National Fire Protection Agency (NFPA) 805, Performance-Based Standard for Fire Protection for LWR Electric Generating Plants
ML14034A050
Person / Time
Site: Cooper Entergy icon.png
Issue date: 02/06/2014
From: Joseph Sebrosky
Plant Licensing Branch IV
To:
Nebraska Public Power District (NPPD)
Sebrosky J
References
TAC ME8551
Download: ML14034A050 (7)


Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 February 6, 2014 LICENSEE: Nebraska Public Power District FACILITY: Cooper Nuclear Station

SUBJECT:

SUMMARY

OF COOPER NUCLEAR STATION JANUARY 28 AND 29, 2014, AUDIT ASSOCIATED WITH LICENSE AMENDMENT REQUEST TO TRANSITION TO NATIONAL FIRE PROTECTION ASSOCIATION 805 STANDARDS (TAC NO. ME8551)

The purpose of this summary is to document the results of an audit performed at Cooper Nuclear Station (CNS) associated with a National Fire Protection Association 805 (NFPA-805) license amendment request (LAR) dated April 24, 2012 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML121220216). The audit was in the area of the probabilistic risk assessment (PRA) portion of the LAR.

The audit plan is documented in a U.S. Nuclear Regulatory Commission (NRC) staff e-mail dated January 13, 2014 (ADAMS Accession No. ML14015A336). Below is a summary of the audit.

Audit Location and Dates The audit was held at the CNS site in Brownville, Nebraska on January 28, and 29, 2014.

Attendees The following NRC staff from the Office of Nuclear Reactor Regulation (NRR), Division of Risk Assessment (ORA), PRA Licensing Branch (APLA) participated in the audit: Hossein Hamzehee, Steve Dinsmore, and Dan O'Neal Nebraska Public Power District (NPPD, the licensee) personnel that participated in substantive discussions included the following:

Ole Olson NPPD Steve Nelson NPPD Steve Meyer Scientech Manuel Saadallah EPM Todd Stevens NPPD James Blum EPM Thomas Shudak NPPD Jim Chapman Scientech Bill Victor NPPD

Information Reviewed During the Audit As discussed in the January 13, 2014, audit plan, the NRC staff discussed PRA-related information associated with NPPD's April 24, 2012, NFPA-805 LAR. During the audit, the NRC staff discussed request for additional information {RAI) responses provided by NPPD by letters dated December 12, 2013, and January 17, 2014 (ADAMS Accession Nos. ML13353A073 and ML14027A425, respectively). As needed, the LAR and previous RAis were discussed.

Supplemental information that would support completion of the NRC staff's review was discussed and provided in Enclosure 1. In addition, the licensee drafted a summary of the PRA discussions and provided it to the NRC staff for reference in the audit trip report. The licensee's summary is provided as Enclosure 2.

Docket No. 50-298

Enclosures:

1. NRC staff Notes on January 28 and 29, 2014, NRC Audit Requests
2. NPPD's Notes on January 28 and and 29, 2014, NRC Audit Requests cc w/encls: Distribution via Listserv

NRC Staff Notes on January 28 and 29, 2014, NRC Audit Requests Aside from the changes or additions discussed below, the NRC staff stated that further probabilistic risk assessment (PRA)-related information to complete the review was not needed at this time although additional information may be identified as the safety evaluation is finalized. The following supplementary information or modifications to the request for additional information (RAI) responses were discussed with the licensee during the audit.

PRA RAI-02b The response to the RAI 02b discussed reduced damage temperatures and additional ignition sources. The staff expressed concern regarding the lack of a clear summary of the integrated final methodology for modelling Kerite cables. The licensee agreed to provide a summary of how Kerite cables were evaluated either as a table entry (in the table to be referenced in the implementation items) or a RAI response that can be referenced in the table.

PRA RAI35 The response to the RAI stated that an updated Table G-1 (of the license amendment request (LAR)) will be provided in a future submittal. After some discussion, the NRC staff stated that an updated Table G-1 is not needed to complete the review and the statement could be retracted.

PRA RAI 14.01 The response to this RAI provided a description and results of the main control room (MCR) re-analysis. The response describes a methodology that uses a single conditional core damage probability (CCDP) of about 0.1 for all MCR abandonment scenarios. The NRC staff questioned the use of a single, relatively low, CCDP for all MCR abandonment scenarios and noted that plant-specific and shutdown capability characteristics were not described sufficiently in the current RAI response before the review could be completed. The licensee agreed to provide additional information to support its proposed use of a single CCDP.

The licensee also agreed to provide additional information including 1) a brief explanation on how the incipient detection scenarios are included in the MCR abandonment risk calculations, and 2) some discussion of the impact of using the single CCDP on the transition change in risk estimate.

PRA RAI40 The response to RAI 40 was discussed extensively. The response includes a Table 1 that indicates how the PRA has been changed or will be changed with a reference to the RAI responses that describe the change. The discussion centered on identifying 1) changes that had been made to the PRA in support of the transition risk estimate, and 2) other changes that have not yet been made but should be made before the licensee uses the PRAto calculate affected changes in risk for post-transition changes as part of the self-approval process. The NRC staff requested that the licensee clarify the status of all the changes. In particular, the Enclosure 1

NRC staff requested the licensee provide a record of the changes and to indicate any planned changes and when these changes will be made. For example, if a link to the RAI response describing each issue/method that was or will be changed was included, the use of fire PRA methods acceptable to the NRC staff should be documented. Subsequent changes to fire PRA methods to alternative acceptable methods may be made using the post-transition change process.

Two fire PRA changes that were in previous RAI response but were not in the current table were identified: PRA RAI 06 (regarding non-suppression probabilities) and PRA RAI 02.h.01 (regarding including the impact of state of knowledge correlations on the risk estimates). The licensee agreed to partially reformat and clarify the entries in the current table, to add the two missing entries, and to identify when the entry has or will be completed. The revised table could then be referenced by an entry in one of the Attachment S tables and incorporated by reference into the license condition. The licensee agreed to consider developing a new Attachment S implementation item that would reference the revised table.

PRA RAI 16.02 The NRC staff indicated that the response to 16.02 did not clearly state that all failures associated with fire induced cable failure were included in the risk evaluations. The licensee agreed to provide a more concise description of how the risk of variance from deterministic requirements (VFDRs) are calculated that would include this information.

Nebraska Public Power District's Notes on January 28 and 29, 2014, NRC Audit Requests PRA RAI 02.h.01 Concern: Wording of S-3.30 does not address what to do if Regulatory Guide (RG) 1.205 couldn't be met (i.e. if NRC approval is necessary).

Resolution: No change required, consistent with Callaway Implementation Item.

Concern: S-3.30 should include updating the model with correlations to state-of-knowledge/

uncertainty.

Resolution: Licensee will include in Supplement to RAI 40. New Implementation item S-3.19 will update the fire probabilistic risk assessment (FPRA) model as described in RAI 40 Supplement (self-approval).

PRA RAI 19.01 Concern: Check on including S-3 Table in scope of Licensing Condition.

Resolution: License Condition 2.C(4) will be reviewed to include both the S-2 and S-3 tables.

However, wording will be included that following implementation of these activities, future changes to these Implementation Items will be made under the change management provisions of this License Condition. (Reference DC Cook, Duane Arnold Energy Center, Callaway)

Concern: Provide a consolidated S-2 and S-3 Table.

Resolution: Licensee will provide updated tables in Supplement.

PRA RAI35 Concern: Clarify Part c that no G-1 Table update is needed.

Resolution: Licensee will provide RAI 35 supplement that no update to G-1 Table is needed for the current plant configuration.

PRA RAI 03.01 Concern: May need clarification to main control room (MCR) abandonment. Refer to RAI 14.01 for methodology revision for incipient detection.

Resolution: Incorporate language in RAI 40 Supplement that details that RAI 14.01 methodology is also used for incipient detection.

Concern: Ensure use of .1 08 in fire PRA update. Include in S-3.30.

Enclosure 2

Resolution: The licensee plans to create S-3.31 to reference RAI 40 table that discusses model update with 108.

PRA RAI 14.01 Concern: Clarify .1 08 is appropriate for MCR abandonment.

Resolution: The licensee will supplement RAI response with additional justification. The licensee will include application with habitability, and loss of control. The licensee will address delta risk changes with increases in 0.1 08.

PRA RAI40 Concern: Need Implementation Item to update fire model and methodologies going forward.

Resolution: The licensee will provide Implementation Item S-3.31 providing this with reference to RAI 40. The licensee will also ensure 02.h.01 recognizes S 3.30 vs. S 3.31.

Concern: Clarify RAI 40 for 02.f(i). 01.

Resolution: This is subconcern from above.

Concern: Convert appropriate "No's" to "Yes's", with appropriate justification.

Resolution: The licensee will include in RAI 40 Supplement.

PRA RAI16.02 Concern: Look at response to see if clarification is needed on how cable damage is considered in variance from deterministic requirements (VFDRs).

Resolution: The licensee will supplement RAI with additional information.

PRA RAI 06 Concern: Add NSP s 1E-3 to response.

Resolution: The licensee will add row to PRA RAI 40 table.

ML13353A073 and ML14027A425, respectively). As needed, the LAR and previous RAis were discussed.

Supplemental information that would support completion of the NRC staff's review was discussed and provided in Enclosure 1. In addition, the licensee drafted a summary of the PRA discussions and provided it to the NRC staff for reference in the audit trip report. The licensee's summary is provided as Enclosure 2.

Please direct any inquiries to me at 301-415-1132 or at Joseph.Sebrosky@nrc.gov.

IRA/

Joseph M. Sebrosky, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-298

Enclosures:

1. NRC staff Notes on January 28 and 29, 2014, NRC Audit Requests
2. NPPD's Notes on January 28 and and 29, 2014, NRC Audit Requests cc w/encls: Distribution via Listserv DISTRIBUTION:

PUBLIC DONeal, NRR LPL4-1 Reading SDinsmore, NRR RidsNrrDorllpl4-1 Resource HHamzehee, NRR RidsNrrLAJBurkhardt Resource LFields, NRR RidsNrrPMCooper Resource JRobinson, NRR ADAMS Accession No. ML14034A050 OFFICE NRR/DORLILPL4-1 /PM NRR/DORLILPL4-1/LA NRR/DRA/APLA/BC NAME JSebrosky JBurkhardt HHamzehee DATE 2/6/14 2/5/14 2/6/14 OFFICE NRR/DORL/LPL4-1 /BC NRR/DORLILPL4-1/PM NAME MMarkley JSebrosky DATE 2/6/14 2/6/14