NRC-2018-0050, Response to Request for Additional Information Regarding License Amendment Request 288, Request to Extend Containment Leakages Rate Test Frequency
| ML18320A062 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 11/16/2018 |
| From: | Craven R Point Beach |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| EPID L-2018-LLA-0097, NRC-2018-0050 | |
| Download: ML18320A062 (6) | |
Text
November 16, 2018 ATIN: Document Control Desk U.S. Nuclear Regulatoq Commission Washington, DC 20555-0001 Point Beach Nuclear Plant, Units 1 and 2 Dockets 50-266 and 50-301 NRC 2018-0050 10 CFR 50.90
Subject:
Response to Request for Additional Information Regarding License Amendment Request 288, Request to Extend Containment Leakage Rate Test Frequency
References:
- 1. N extEra Energy Point Beach, LLC letter NRC 2018-0018 "License Amendment Request 288, Request to Extend Containment Leakage Rate Test Frequency," March 30, 2018 (ML18092A239)
- 2. NRC e-mail "Final Request for Additional Information - License Amendment Request 288 to Extend Containment Leakage Rate Test Frequency for Point Beach Nuclear Plants, Units 1 and 2-EPID L-2018-LLA-0097," October 15, 2018 In Reference 1, NextEra Energy Point Beach, LLC (NextEra) submitted a license amendment request (LAR) for the Point Beach Nuclear Plant, Units 1 and 2. The proposed change would revise TS 5.5.15, "Containment Leakage Rate Testing Program," to require a program in accordance with Nuclear Energy Institute (NEI) topical report NEI 94-01, Revision 3-A, "Industry Guideline for Implementing Performance-Based Option of 10 CFR Part 50, Appendi"XJ."
In Reference 2, the NRC staff requested additional information to support its review of the LAR.
The enclosure to this letter provides the requested information.
This response does not alter the conclusions in Reference 1 that the proposed change does not involve a significant hazards consideration pursuant to 10 CFR 50.92, and there are no significant environmental impacts associated with the change.
This letter contains no new or revised regulat01y commitments.
Should you have any questions regarding this submittal, please contact Mr. Eric Schultz, Licensing Manager, at 920-755-7854.
NextEra Energy Point Beach, LLC 6610 Nuclear Road, Two Rivers, WI 54214
I declare under penalty of perjmy that the foregoing is hue and correct.
Executed on NoJ IS"', 2018 Sincerely, Robert Craven Site Director NextEra Energy Point Beach, LLC Enclosure cc:
Administrator, Region III, USNRC Project Manager, Point Beach Nuclear Plant, USNRC.
Resident Inspector, Point Beach Nuclear Plant, USNRC Public Service Commission of Wisconsin NRC 2018-0050 Page 2 of2
Enclosure Response to Request for Additional Information PRA RAI 01 - Addition of FLEX into the PRA Models NRC 2018-0050 Enclosure Page 1 of 4 In order to meet certain NRC regulations and orders (such as NRC Order EA-12-049, "Issuance of Order to Modify Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events," issued after the Fukushima Dai-ichi accident),
licensees have developed and integrated mitigating strategies into plant operations including Diverse and Flexible Coping Strategies (FLEX). As these changes are implemented, licensees are starting to inc01porate these new strategies into their PRA models.
The Staff has identified several challenges to inco1porating these new strategies into PRA models. The NRC memorandum dated May 30, 2017, "Assessment of the Nuclear Energy Institute 16-06, 'Crediting Mitigating Strategies in Risk-Informed Decision Making,' Guidance for Risk-Informed Changes to Plants Licensing Basis" (ADAMS Accession No. Iv1L17031A269),
provides the NRC's staff assessment of challenges to inc01porating FLEX equipment and strategies into a PRA model in support of risk-informed decision making in accordance with the guidance of RG 1.200.
In order for the staff to complete it's review, please provide the following information:
- 1. Clarify whether mitigating strategies (i.e., FLEX) ate incorporated into the PRA models (e.g., internal events PRA, fire PRA, etc.) that are used in this LAR. If so,
- a. Confirm that plant-specific data is used to develop the failure probabilities.
- b. Describe the human reliability analysis (HRA) methods used.
NextEra Response The referenced letter (ML17031A269) is concerned with crediting FLEX mitigating strategies for pmposes other than those for which they were designed, primarily using portable equipment that was implemented specifically for FLEX. No portable FLEX mitigating strategies are inco1porated into the Point Beach PRA models used in this LAR. The only FLEX equipment that is included in the PRA models is permanendy installed plant equipment, specifically the reactor coolant pump seals and the auxiliaty feedwater ctosstie capability. These permanent plant modifications were already credited in Amendments 256 and 260, Transition to a Risk-Informed, Performance Based I:"ire Protection Program :!n Accordance with 10 CfR 50.48(c). Crediting a~ditional FLEX mitigating strategies would increase capabilities to restore or maintain core cooling, containment, and spent fuel pool cooling in the event of beyond-design-basis events. By not crediting additional FLEX mitigating strategies, the PRA models used in the LAR 288 risk assessment, and the CDF and LERF values upon which the conclusions ate based, are conservative with respect to the current plant configuration.
NRC 2018-0050 Enclosure Page 2 of 4 SCPB RAI-1 REGULATORY BASIS.
10 CFR SO, Appendix J, Option B,Section V.B.3, requires that the RG or other implementation document used by a licensee to develop a performance-based leakage-testing program be included, by general reference, in the plant TSs.
Point Beach Nuclear Plant, Units 1 and 2 Technical Specification S.S.15, "Containment Leakage Rate Testing Program," currently invokes as its implementation documents both:
Regulat01y Guide 1.163, "Performance-Based Containment Leak Test Program,"
dated September 199S NEI 94-01, Rev. 0, Industry Guidance for Implementing Performance Based Option of 10 CFR SO, Appendi'{ J ISSUE LAR Section 3.1.2, "Type B and Type C Testing," states, in part:
For Type B testing, S penetrations for Unit 1 and 6 penetrations for Unit 2 are currently on extended frequency. For both Units 1 and 2, two penetrations (each) are tested when the penetrations are opened. If these penetrations ate not opened for multiple outages, the penetrations are eligible for extended frequency testing. Measured leakage for these penetrations has not changed significantly over 120 months.
"Table 1 - Extended Frequency Percentages" of LAR Section 3.1.2 indicates that there are 13 total Type B Penetrations for Unit 1 and 14 total Type B Penetrations for Unit 2.
From the information and data available in the LAR and PBNP UFSAR, the staff cannot accurately interpret the "% Extended" (i.e., 38.S% Unit 1; 42.9% Unit 2) data contained in Table 1. In particular, for Unit 1 ate there six (i.e., 13 - S - 2) containment Type B penetrations not on an extended test intervals because of: (a) Type B test failures or (b) these six penetrations are opened each refueling outage and therefore not eligible for extended test intervals. Similarly, for Unit 2 are there six (i.e., 14 2) containment Type B penetrations not on an extended test intervals because of: (a) Type B test failures or (b) these six penetrations are opened each refueling outage and therefore not eligible for extended test intervals.
REQUEST For an established Appendix J, Option B, LLRT program with a sufficient historical base, the percentage of Type B or Type C components on repetitive frequencies can indicate the quality of the maintenance pr?gram and corrective a~tion process.
Provide the following information for PBNP Units 1 and 2:
(a) The total number (i.e., population) and percentage of the total number of eligible PBNP Type B tested components currently on a 120-month extended performance-based test interval (b) The total population of electrical penetrations each in Unit 1 and in Unit 2.
N extEra R esp onse NRC 2018-0050 Enclosure Page 3 of 4 NextEra discussed SCPB RAI-1 with NRC staff during a clarification call on October 10, 2018.
NextEra agreed to provide additional information for type B penetrations, and the NRC staff agreed that providing the total population of electrical penetrations (other than type B) in each Unit was unnecessary.
Unit 1 Type B Penetration Sum mary:
The total population of penetrations that requite Type B testing for PBNP Unit 1 is 13. None of the eligible penetrations ate on a 120-month extended performance based test frequency. None of the eligible penetrations have failed to meet their administrative limits or have adverse maintenance history. NextEra has conservatively elected to test the eligible penetrations more often as an early detection and preventative maintenance technique.
Five of the 13 penetrations ate electrical penetrations currently on a 3R (refueling) extended test frequency. These penetrations have an excellent test/ maintenance histoty and ate eligible for testing on a 120-month extended test frequency in the future. The higher test frequency is considered an Appendix ] program conservatism.
There ate four Unit 1 mechanical penetrations that are eligible for testing on an extended test frequency. Three of the four penetrations are opened each outage and will remain on a 1R frequency. The remaining penetration is the equipment hatch flange seal, which is currently scheduled on a 1R frequency and is eligible for a 120-month frequency. However, since the flange is periodically opened during refueling outages it is not likely to teach a 120-month test frequency.
Testing of the equipment hatch flange seal will continue to be performed at a test frequency not to exceed 120 months and whenever the hatch has been removed during refueling outages.
There ate four Unit 1 mechanical penetrations that ate considered not eligible for an extended test frequency. These include the equipment airlock, personnel airlock, and the purge exhaust and supply flanges. These penetrations ate tested on a 1R frequency.
Unit 1 - Type B Penetrations Eligible Currently CURRENT FUTURE Item Penetration Penetration Description Outage Use for On TEST FREQUENCY No.
No.
Extended Extended Freq Frequency FREQ CHANGE 1
PSS Cap B (filler colic soarel and Blank Fiance Used Each Oula!le Yes Nil 1R No 2
PC-1 C-1 EquiJ!'ment Airlock Used Each Outag:e Nil Nc*
1R No 3
PC-2 C-2 Pers c M el Airlock Used Each Oula!lle No
- No 1R No 4
P0-58 Electrical penetration Not Used Y es Yes 3R Yes-120 Months 5
P0-21 Electrical !lenetration Not Used Yes Yes
~R Yes -120 Months 6
P0-22 Electrical penetration Not Used Y es Yes
- lR Yes-120 Months 7
P0-28 Electrical penetration Not Used Y es Y es 3R Y es-120 Months 8
P0-54 Electrical penetration Not Used Y es Yes 3R Yes-120 Months 9
PC-3 Fuel Transfer Tube Penetration Used Each Outa!le Yes Nil 1R No 10
\\11 Puree Exhaust Flanne Used Each Outacre No t*f()
1R No 11
\\12 Pu rt:e Su ppl r Fla n ae Used Each Outa()e No
~I'D 1R Ho 12 C-3 Fuei Transfer Tube Closure Assembly Used Each Ou!Bg:e Yes t*f()
1R
~[O 13 C-1 E{!,uipment Hatch. Flange Seal Yes-120 Months J Typically Used Each. Outage Yes No lR Test if used.
Unit 2 Type B Penetration Summary:
NRC 2018-0050 Enclosure Page 4 of 4 The total population of penetrations that require Type B testing for PBNP Unit 2 is 14. One (7%)
of the eligible penetrations is on a 120-month extended performance based test frequency. None of the eligible penetrations have failed to meet their administrative limits or have adverse maintenance histoty. NextEra has conservatively elected to test the eligible penetrations more often as an early detection and preventative maintenance technique.
Five of the 14 penetrations are electrical penetrations cw:rendy on a 3R extended test frequency.
These penetrations have an excellent test/ maintenance histoty and are eligible for testing on a 120-month extended frequency in the future. The higher test frequency is considered an Appendi.'C J program conservatism.
There are five Unit 2 mechanical penetrations that are eligible for testing on an extended test frequency. One of the five penetrations, the eddy cw:rent test penetration is cw:rendy on a 120-month extended test frequency. Three of the five penetrations are opened each outage and will remain on a 1R frequency. The remaining penetration is the equipment hatch flange seal, which is cw:rently scheduled on a 1R frequency and is eligible for the 120-month frequency. However, since the flange seal is periodically opened during refueling outages, it is not likely to reach a 120-month test frequency. Testing of the equipment hatch flange seal will continue to be performed at an interval not to exceed 120 months and whenever the hatch has been removed dw:ing refueling outages There are fow: Unit 2 mechanical penetrations that are considered not eligible for an extended test interval. These include the equipment airlock, personnel airlock, and the pw:ge exhaust and supply flanges. These penetrations are tested on a 1R interval.
Unit 2-Type B Penetrations Eligible Currently CURRENT FUTURE Item Penetrati on Penetration Description Outage Use for On TEST FREQUENCY No.
No.
Extended Extended Freq Frequency FREQ CHANGE 1
PES Cap B (fiber optic spare) and Blank Flanqe Used Each Outaqe Yes
~f()
1R No 2
PC-1 C-1 Equipment Airlock Used Each Outa!le No No 1R No 3
PC-2 C-2 Personnel Airlock Used Each Outaqe No No 1R No 4
P0-58 Electrical penetration Not Used Yes Yes 3R Yes-120 lolonths 5
P0-20 Electrical penetration Net Used Yes Yes 3R Yes-120 lolonths 6
P0-22 Electricai i'Jenetralion Not Used Yes Yes 3R Yes - 120 Months 7
P0-1 Electrical penetration Not Used Yes Yes 3R Yes - 120 lolonths 8
P0-54 Electrical penetration Not Used Yes Yes 3R Yes - 120 lolonths 9
PC-3 Fuel Transfer Tube Penetration Used Each Outaqe Yes No 1R No 10 V1 Purge Exhaust Flange Used Each Outage No No 1R No 11 V2 Purg_e Supply_ Fiance Used Each Outaae No No 1R No 12 C-3 Fuel Transfer Tube Closure Assembly Used Each Outage Yes No 1R No 13 C-1 Equipm~nt Hatch Flange Seal Yes - 120 f,lonlhs I
- Typically Used Each Outage Yes Nc*
1R Test if ~ sed.
14 P07-2 Eddy Current Test Penetration Not used each cutaqe Yes Yes 120 Months No