ML15175A071
| ML15175A071 | |
| Person / Time | |
|---|---|
| Site: | Catawba  |
| Issue date: | 07/02/2015 |
| From: | Martin R Plant Licensing Branch II |
| To: | Henderson K Duke Energy Carolinas |
| Martin R | |
| References | |
| TAC MF2936, TAC MF2937 | |
| Download: ML15175A071 (7) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION Mr. K. Henderson Site Vice President
- Catawba Nuclear Station.
Duke Energy Carolinas, LLC 4800 Concord Road York, NC 297 45 WASHINGTON, D.C. 20555*0001 July 2, 2015
SUBJECT:
CATAWBA NUCLEAR STATION, UNITS 1AND2: REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST TO IMPLEMENT A RISK-INFORMED, PERFORMANCE-BASED FIRE PROTECTION PROGRAM (TAC NOS. MF2936 AND MF2937)
Dear Mr. Henderson:
By letter dated September 25, 2013 (Agencywide Documents Access.and Management System (ADAMS) Accession No. ML13276A503), Duke Energy Carolinas, LLC (Duke) submitted a license amendment request to change its fire protection program to one based on the National Fire Protection Association (NFPA) Standard-805, "Performance-Based Standard for Fire Protection for Light Water Reactor Electric Generating Plants," 2001 Edition.
On April 28, 2015, Duke submitted a response to requests for additional information. The U.S.
Nuclear Regulatory Commission staff has determined that follow-up requests for information are necessary, as provided in the enclosure.
Docket Nos. 50-413 and 50-414
Enclosure:
As stated cc w/encl: Distribution via Listserv Sincerely,
/J6bMt>~f~
(~?b Martin, Senior Project Manager Plant Licensing Branch 11-1 Division of Operating Reactor Licensing*
Office of Nuclear Reactor Regulation
- REQUEST FOR ADDITIONAL INFORMATION (RAI)
ADOPTION OF NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)
STANDARD 805 FOR FIRE PROTECTION DUKE ENERGY CAROLINAS, LLC (DUKE)
CATAWBA NUCLEAR STATION, UNITS 1 AND 2 DOCKET NOS. 50-413, 50-414 By letter dated September 25, 2013 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13276A503), Duke Energy Carolinas, LLC (Duke) submitted a license amendment request (LAR) to change its fire protection program to one based on the National Fire Protection Association (NFPA) Standard-805, "Performance-Based Standard for Fire Protection for Light Water Reactor Electric Generating Plants," 2001 Edition.
On April 28, 2015, Duke submitted a response to requests for additional information (RAI). The U.S. Nuclear Regulatory Commission (NRC) staff has determined that follow-up requests for information are necessary, as provided in the enclosure.
Follow-up to April 28, 2015 Response to PRA RAI 03 Probabilistic Risk Assessment (PRA) RAI 05.01 The response to probabilistic risk assessment (PRA) RAI 05 provides the results of an uncertainty analysis on the total fire core damage frequency. (CDF) and large early release frequency (LERF), that includes accounting for state of knowledge correlations, but no corresponding results are provided for delta risk. Provide the results of the uncertainty analysis impact on the mean delta risk results and discuss if the Regulatory Guide 1.17 4 risk guidelines are met using the mean results.
PRA RAI 03.b.01 The response to PRA RAI 03.b states that an updated Fire PRA (FPRA) niodel was created to incorporate the changes made to as described in the following RAI responses. The response further states that this model wilL become the self-approval post-transition model.
PRA RAI 01.b.i PRA RAI 05 PRA RAI 09 PRA RAI 14 o
PRA RAI 15 PRA RAI 17.a, 17.b, and 17.c PRA RAI 20 FM RAI 01.a through 01.f FM RAI 04 The response to PRA RAI 03.d states that analysis refinements that only required clarification or additional justification have been addressed in respons.e to specific RAls listed below and t_he original methods will be retained in the Fire PRA and will be used to estimate the change in risk of post-transition changes with no fUrther adjustments or sensitivities to account for their use.
PRA RAI 02.a, 02.b, 02.c PRA RAI 08 PRA RAI 10 PRA RAI 11 PRA RAI 12 PRA RAI 18 PRA RAI 19 PRA RAI 21 FM RAI 01.i FM RAI 01.1 The NRC staff's interpretation of the response to some of the individual issues (i.e., RAls) in the above response to PRA RAI 03.b is summarized in the table below. Please confirm or correct the Status of Resolution entries for both the transition aggregate PRA and the post transition PRA model in the following table.
Licensee Response Status of Resolution Transition aggregate PRA/post-transition PRA PRA RAI 01.b regarding the The January 13, 2015 response to RAI Unclear if multiplier method is Fire PRA HRA 04.b on safety margins stated that the no longer used. Confirm that multiplier approach is used. The the NUREG-1921 methodology January 28, 2015 response to RAI 01.b has been followed in applying states that the NUREG-1921 HEP and JHEP values and the methodology has been reviewed and an impact has been assessed in application of this method with response to PRA RAI 03.
screening or detailed HRA, as appropriate, will be included in the updated risk results as part of the PRA RAI 03 response.
PRA RAI 05 regarding In support of the Catawba RAI PRA 03 Summarize actions taken in application of SOKC response, the uncertainty analysis is response to PRA RAI 05.01 being updated to account for SOKCs for regarding the results of the circuit failure likelihood, hot short uncertainty analysis impact on duration, severity factors, and non-the mean delta risk results suppression probabilities. SOKC would only need to be addressed for SFs and NSPs if there is more than one NSP or SF in a cut set.
PRA RAI 09 regarding a) The conditional hot short Summarize actions taken in reduced circuit failure probabilities have been either updated response to RAI 17.b.Ol probabilities to the appropriate circuit failure regarding including hot short probabilities for single break or double probabilities (referenced in RAI break control circuits or have been 09.f) confirmed to bound the NUREG/CR-7150 values, b) Option #2 of NU REG/CR-6850 was not used in the original Catawba FPRA for developing any of the conditional hot short probabilities, c) hot short duration probabilities have been updated to the new values of NUREG/CR-7150, d) the conditional hot r
short probabilities have been either updated to the appropriate aggregate circuit failure probabilities for single break or double break control circuits or have been confirmed to bound the NUREG/CR-7150 aggregate values, e) uncertainty values for circuit failure probabilities and spurious operation duration will be included into the updated SOKC analysis, and f) the conditional hot short probabilities for trunk cables and panel wiring have either been updated to the appropriate aggregate circuit failure probabilities or have been confirmed to bound the NUREG/CR-7150 values. Those updated values will be provided in response to RAI PRA 03.
PRA RAI 11.c regarding c) Stated that the timing considerations Summarize action taken in main control room (MCR) will be prepared consistent with response to PRA RAI 11.01.d abandonment on loss of McGuire and the event will be that this intended evaluation habitability quantified as part of RAI PRA 03.
has been completed.
PRA RAI 12 regarding A sensitivity study was performed to Summarize action taken in treatment of recovery review the scenarios in Fire Areas 1, 2, response to PRA RAI 12.01 actions. (Licensee to 3, 4, 9, 10, 11, 18, and 22 for modeled regarding identifying recovery replace with response to actions taken outside the MCR that actions.
12.02.)
might be recovery actions.
PRARAI 17.a regarding fire The impact on the total CDF/LERF and Summarize action taken in propagation from electrical delta CDF/LERF due to fire propagating response to PRA RAI 17.a.Ol cabinets and fire frequency outside of well-sealed and robustly regarding use of the method allocation/screening secured MCCs will be further assessed described in the final version in the integrated analysis performed in of FPRA FAQ 14-0009 response to RAI PRA 03, using the method outlined in Fire PRA FAQ 14-0009.
PRA RAI 17.b regarding The targets impacted. by the Summarize action taken in treatment of spurious propagating fire will be evaluated for response to PRA RAI 17.b.01 actuation for cabinet fires spurious operations using the aggregate regarding applying the
\\_
hot short probabilities.
guidance on conductor bundles within a cabinet in NU REG/CR-7150 PRA RAI 17.c regarding The impact of the per-cabinet Bin 15 Summarize action taken in well-sealed cabinets less fire frequency on the Fire PRA results response to PRA RAI 17.c.01 than 440V in the Bin 15 will be assessed in the integrated regarding the CDF and LERF count analysis performed in response to RAI associated with Bin 15 cabinet PRA 03. Appropriate electrical cabinets fires and the percentage of will be removed from Bin 15 by that CDF and LERF from following the guidance in NU REG/CR-cabinets that are less than 6850. This revised Bin 15 count, along 440V with the corresponding per-cabinet fire frequency, will be used in the final post-transition Fire PRA quantification.
PRA RAI 19 regarding An MSO expert panel will be held to Unclear if work has been modeling of multiple establish and document an official completed. Confirm that the spurious operations position regarding Fire PRA modeling MSO expert panel evaluation (MSOs) impacts of new MSO Scenarios 14, 52,
. has been completed and and 53. Any Fire PRA model impact, or explain whether PRA model justification of non-applicability as a was updated in response to RAI result of this further evaluation, will be PRA 03 following the panel included in response to RAI PRA 03.
evaluation.
FM RAI 01.i regarding fire Catawba specification CNS-1390.01 Summarize action taken in propagation from armored 0086 provides high confidence that any response to RAI 01.i.(i).Ol cable jacketed cable related to the Fire PRA analysis is very minimal. Armored cables similar to the types used at Duke Energy nuclear power generating stations exhibit flame propagation characteristics consistent with cable types considered non-propagating or IEEE-383 or equivalent "qualified".
FM RAI 01.I regarding non-The only non-cable intervening Summarize action taken in cable intervening combustible identified at Catawba with response to RAI 01.1.01 combustibles the potential to impact any fire scenario, is the installed above-ground high-density polyethylene (H DPE)
. piping. The existing HDPE piping was evaluated as not contributing to any Fire PRA scenarios.
PRA RAI 03.b.02 The responses to PRA RAI 03.a and 03.b do not identify PRA RAls 02.f.e and 22 which, according to their respective RAI responses, could result in changes to the PRA. Provide a summary of the disposition to PRA RAls 02.f.e and 22 in the aggregate PRA and the post-transition PRA.
ML15175A071 Sincerely,
/RAJ Bob Martin, Senior Project Manager Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation RidsNrrDorllpl2-1 Resource RidsNrrPMCatawba Resource RidsRgn2MailCenter Resource
- via E-mail OFFICE NRR/LPL2-1 /PM NRR/LPL2-1/LA NRR/DRA/AFPB NRR/LPL2-1/BC NRR/LPL2-1/PM NAME BMartin SFigueroa AKlein* (LFields for) RPascarelli BMartin DATE 07/02/15 06/30/15 06/17/15
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