ML16069A139

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NRR E-mail Capture - Catawba Nuclear Station, 1 and 2- Tec Review Checklist Supporting Implementation of NTTF Recom 2.1, Seismic, Related to the Fukushima DAI-ICHI Nuclear Power Plant Accident
ML16069A139
Person / Time
Site: Catawba  Duke energy icon.png
Issue date: 03/09/2016
From: Michael Mccoppin
Office of New Reactors
To: Mohamed Shams
Japan Lessons-Learned Division
References
MF5233, MF5234
Download: ML16069A139 (12)
v • d • e


Text

NRR-PMDAPEm Resource From: McCoppin, Michael Sent: Wednesday, March 09, 2016 8:13 AM To: Shams, Mohamed; Wyman, Stephen Cc: DiFrancesco, Nicholas; Spence, Jane; Devlin-Gill, Stephanie; Patterson, Eric; Le, Tuan; Heeszel, David; Yee, On; Rivera-Lugo, Richard; Tseng, Ian; 50.54f_Seismic Resource; RidsNroDsea Resource; Andrukat, Dennis; Schleicher, Lisa

Subject:

Catawba ESEP Checklist Attachments: Catawba R2 1 ESEP Review Final IHT 030816_Revised.docx March 4, 2016 MEMORANDUM TO: Mohamed K. Shams, Chief Hazards Management Branch (JHMB)

Japan Lessons-Learned Division Office of Nuclear Reactor Regulation FROM: Michael McCoppin, Chief Geosciences and Geotechnical Engineering Branch 2 (RGS2)

Division of Site Safety and Environmental Analysis Office of New Reactors

SUBJECT:

CATAWBA NUCLEAR STATION, UNITS 1 AND 2- TECHNICAL REVIEW CHECKLIST RELATED TO INTERIM EXPEDITED SEISMIC EVALUATION PROCESS SUPPORTING IMPLEMENTATION OF NTTF RECOMMENDATION 2.1, SEISMIC, RELATED TO THE FUKUSHIMA DAI-ICHI NUCLEAR POWER PLANT ACCIDENT (TAC NO. MF5233, and MF5234)

The NRC technical staff working through the Geosciences and Geotechnical Engineering Branches 1 and 2 (RGS1 and RGS2) completed the Technical Review Checklist of the CATAWBA NUCLEAR STATION, UNITS 1 AND 2 response to Enclosure 1, Item (6) of the March 12, 2012, request for information letter issued per Title 10 of the Code of Federal Regulations, Subpart 50.54(f), to power reactor licensees and holders of construction permits requesting addressees to provide further information to support the NRC staffs evaluation of regulatory actions to be taken in response to Fukushima Near-Term Task Force (NTTF) Recommendation 2.1: Seismic which implements lessons learned from Japans March 11, 2011, Great Thoku Earthquake and subsequent tsunami. The addresses the staff review of the interim Expedited Seismic Evaluation Process (ESEP) report in response to Requested Item (6) of Enclosure 1, Recommendation 2.1: Seismic, of the 50.54(f) letter. Attached is a file containing the technical review checklist to prepare a response letter to the licensee.

The NRC staff reviewed the information provided and, as documented in the enclosed staff checklist, determined that sufficient information was provided to be responsive to this portion of the Enclosure 1 of the 50.54(f) letter. The application of this staff review is limited to the interim ESEP as part of NTTF R2.1: Seismic activities.

This electronic memo constitutes the DSEA concurrence provided that only editorial changes are made to the staff assessment that would not affect the technical conclusions or technical context of the assessment.

This concludes the NRCs efforts associated with TAC NO. MF5233 and MF5234 for the review of the interim ESEP report for the CATAWBA NUCLEAR STATION, UNITS 1 AND 2.

1

Docket No: 50-413 and 50-414 CONTACT: Stephanie Devlin-Gill Office of New Reactors 301-415-5301 Copy: Nicholas DiFrancesco, Steve Wyman, Jane Spence, Stephanie Devlin-Gill, Dennis Andrukat, On Yee, George Wang, Ian Tseng, Lisa Schleicher, Richard, Rivera-Lugo, Nikolaos Simos, (NRC Consultant) , 50.54f Seismic Resource, RidsNroDsea Resource Mike McCoppin, MBA, PMP Branch Chief, Radiation Protection &

Accident Consequences (RPAC)

Office of New Reactors United States Nuclear Regulatory Commission Mail Stop: T7-F03 Office: T7-F18 Ph: 301.415.6533 Cell: 202.731.1423 FAX: 301.415.5399 Email:michael.mccoppin@nrc.gov CONFIDENTIALITY NOTICE: This electronic message is intended to be viewed only by the individual or entity to whom it is addressed. It may contain information that is privileged, confidential and exempt from disclosure under applicable law. Any dissemination, distribution or copying of this communication is strictly prohibited without prior permission. If the reader of this message is not the intended recipient, or the employee or agent responsible for delivering the message to the intended recipient, or if you have received this communication in error, please notify me immediately by return e-mail and delete the original message and any copies of it from your computer system.

2

Hearing Identifier: NRR_PMDA Email Number: 2695 Mail Envelope Properties (7e0f4063a5584db5a518613429409292)

Subject:

Catawba ESEP Checklist Sent Date: 3/9/2016 8:12:30 AM Received Date: 3/9/2016 8:12:31 AM From: McCoppin, Michael Created By: Michael.McCoppin@nrc.gov Recipients:

"DiFrancesco, Nicholas" <Nicholas.DiFrancesco@nrc.gov>

Tracking Status: None "Spence, Jane" <Jane.Spence@nrc.gov>

Tracking Status: None "Devlin-Gill, Stephanie" <Stephanie.Devlin-Gill@nrc.gov>

Tracking Status: None "Patterson, Eric" <Eric.Patterson@nrc.gov>

Tracking Status: None "Le, Tuan" <Tuan.Le@nrc.gov>

Tracking Status: None "Heeszel, David" <David.Heeszel@nrc.gov>

Tracking Status: None "Yee, On" <On.Yee@nrc.gov>

Tracking Status: None "Rivera-Lugo, Richard" <Richard.Rivera-Lugo@nrc.gov>

Tracking Status: None "Tseng, Ian" <Ian.Tseng@nrc.gov>

Tracking Status: None "50.54f_Seismic Resource" <50.54f_Seismic.Resource@nrc.gov>

Tracking Status: None "RidsNroDsea Resource" <RidsNroDsea.Resource@nrc.gov>

Tracking Status: None "Andrukat, Dennis" <Dennis.Andrukat@nrc.gov>

Tracking Status: None "Schleicher, Lisa" <Lisa.Schleicher@nrc.gov>

Tracking Status: None "Shams, Mohamed" <Mohamed.Shams@nrc.gov>

Tracking Status: None "Wyman, Stephen" <Stephen.Wyman@nrc.gov>

Tracking Status: None Post Office: HQPWMSMRS07.nrc.gov Files Size Date & Time MESSAGE 3726 3/9/2016 8:12:31 AM Catawba R2 1 ESEP Review Final IHT 030816_Revised.docx 58579 Options Priority: Standard Return Notification: No Reply Requested: No

Sensitivity: Normal Expiration Date:

Recipients Received:

TECHNICAL REVIEW CHECKLIST BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO EXPEDITED SEISMIC EVALUATION PROCESS INTERIM EVALUATION IMPLEMENTING NTTF RECOMMENDATION 2.1 SEISMIC CATAWBA NUCLEAR STATION, UNITS 1 AND 2 DOCKET NOS. 50-413 AND 50-414 By letter dated March 12, 2012 (USNRC, 2012a), the U.S. Nuclear Regulatory Commission (NRC) issued a request for information to all power reactor licensees and holders of construction permits in active or deferred status, pursuant to Title 10 of the Code of Federal Regulations (10 CFR), Section 50.54(f) Conditions of License (hereafter referred to as the 50.54(f) letter). Enclosure 1 of the 50.54(f) letter requests addressees to reevaluate the seismic hazard at their site using present-day methods and guidance for licensing new nuclear power plants, and identify actions to address or modify, as necessary, plant components affected with the reevaluated seismic hazards. Requested Information Item (6) in Enclosure 1 to the 50.54(f) letter requests addressees to provide an interim evaluation and actions taken or planned to address a higher seismic hazard relative to the design basis, as appropriate, prior to completion and submission of the seismic risk evaluation.

Additionally, by letter dated April 12, 20131, the Electric Power Research Institute (EPRI) staff submitted EPRI TR 3002000704 Seismic Evaluation Guidance: Augmented Approach for the Resolution of Fukushima Near-Term Task Force (NTTF) Recommendation 2.1: Seismic (hereafter referred to as the guidance). The Augmented Approach proposed that licensees would use an Expedited Seismic Evaluation Process (ESEP) to address the interim actions as requested by Information Item (6) in the 50.54(f) letter. The ESEP is a simplified seismic capacity evaluation with a focused scope of certain key installed Mitigating Strategies equipment that is used for core cooling and containment functions to cope with scenarios that involve a loss of all AC power and loss of access to the ultimate heat sink to withstand the Review Level Ground Motion, which is up to two times the safe shutdown earthquake (SSE).

Due to the expedited and interim nature of the ESEP, the assessment does not include many considerations that are part of a normal risk evaluation. These deferred items, include but are not limited to, structures, piping, non-seismic failures, and operator actions, as well scenarios such as addressing loss of coolant accidents. By letter dated May 7, 20132, the NRC staff endorsed the guidance. Central and eastern United States licensees with a reevaluated seismic hazard exceeding the SSE submitted an ESEP interim evaluation in December 2014.

Consistent with the interim nature of this activity, the staff performed the review of the licensees submittal to assess whether the intent of the guidance was implemented. A multi-disciplined team checked whether the identified methods were consistent with the guidance. A senior expert panel reviewed the teams questions, if any, and checklist for consistency and scope.

New or updated parameters (e.g., In-Structure Response Spectra, High Confidence of Low Probability of Failure calculations) presented by the licensees were assessed only based on licensee statements for acceptability for the Item (6) response. The application of this staff review is limited to the ESEP interim evaluation as part of NTTF R2.1: Seismic activities.

1 ADAMS Accession No. ML13102A142 2 ADAMS Accession No. ML13106A331

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2 By letter dated December 31, 2014,3 Duke Energy Carolina, LLC (the licensee) provided an Expedited Seismic Evaluation Process (ESEP) report in a response to Enclosure 1, Requested Information Item (6) of the 50.54(f) letter, for the Catawba Nuclear Station, Units 1 and 2 (Catawba).

I. Review Level Ground Motion The licensee:

  • described the determination of the review level ground motion Yes (RLGM) using one of the means acceptable by the guidance (see Note 1) Yes
  • identified location of the control point and is consistent with March 2014 Seismic Hazard and Screening Report4 submittal Yes
  • compared the site ground motion response spectra used to select the ESEP RLGM to the SSE.

Catawba used a scaled SSE at a ratio of 1.91 at 10 Hz Notes from the Reviewer:

1. The licensee did not provide the SSE with all of the values used to calculate the RLGM. However, using the information in Figure 4-3, the staff was able to generally reproduce the licensees RLGM when using the SSE information digitized from Figure 4-3 rather than the information in Table 4-1 of the ESEP. This is acceptable for the purposes of this interim evaluation.

Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies were identified.

The NRC staff concludes:

  • the licensees RLGM meets the intent of the guidance Yes
  • the RLGM is reasonable for use in the interim evaluation. Yes II. Selection of the Success Path The licensee:
  • described the success path Yes
  • described normal and desired state of the equipment for the Yes success path
  • ensured that the success path is consistent with the plants overall Yes mitigating strategies approach or provided a justification for an alternate path
  • stated that the selection process was in accordance with the Yes guidance or meets the intent of the guidance
  • used installed FLEX Phase 1 equipment as part of the success Yes path
  • included FLEX Phase 2 and/or 3 connections Yes

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2 Notes from the Reviewer:

None Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies identified.

The NRC staff concludes that:

  • the selected success path is reasonable for use in the interim evaluation Yes
  • the licensee considered installed Phase 2 and 3 connections or equipment in the interim evaluation. Yes III. Selection of the Equipment List The licensee:
  • developed and provided the ESEL by applying the ESEP Yes
  • identified equipment considering the following functions:

o Core cooling (with focus on Mode 1) function Yes o Available, sustainable water source Yes o Containment function and integrity Yes Notes from the Reviewer:

None Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies identified.

For PWR Plants ONLY The licensee included indicators / instrumentation for the following functions: level, pressure, temperature, that would be indicative of (but not Yes explicitly identified to specific instruments): water level of the steam generator (SG), pressure of SG, containment, and reactor coolant system (RCS); and temperature of the RCS.

For BWR Plants ONLY The licensee considered indicators for the following functions:

level, pressure, temperature that would be indicative of (but not explicitly N/A identified to specific instruments): Temperature of suppression pool, RCS, containment); Pressure of suppression pool, RCS, and drywell; water level of the suppression pool.

Notes from the Reviewer:

None Deviation(s) or Deficiency(ies), and Consequence(s):

No deviations or deficiencies identified.

3

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2 Through a sampling of the ESEP key components, the NRC staff concludes that:

  • the licensees process to develop the ESEL meets the intent of the Yes guidance for the interim evaluation
  • the desired equipment state for the success path were identified Yes
  • the licensee considered the support equipment for the ESEL Yes
  • both front-line and support systems appeared to be included in the Yes ESEL as evidenced by inclusion of SSCs on the success path and of support systems (e.g., batteries, motor control centers, inverters).

IV. Walkdown Approach The licensee:

  • described the walkdown screening approach, including walkbys Yes and walkdowns performed exclusively for the ESEP, in accordance with the guidance
  • credited previous walkdown results, including a description of Yes current action(s) to verify the present equipment condition and/or configuration (e.g., walk-bys), in accordance with the guidance
  • stated that the walkdown was performed by seismically trained Yes personnel Notes from the Reviewer:
1. The licensee stated that credit was given to the previous walkdowns since these walkdowns were performed by qualified Seismic Review Teams, but they do not state the qualifications of the ESEP Seismic Review Team. The licensee was requested to provide more information on the qualification of the personnel that performed the plant seismic walkdowns. In its response, dated June 23, 2015 (ML15175A457), the licensee provided information on the ESEP Seismic Review Team members, which sufficiently demonstrates their training and qualification levels.

Deviation(s) or Deficiency(ies), and Resolution:

The reviewer did not find any deviations or deficiencies.

The licensee:

  • described, as needed, adverse material condition of the equipment Yes (see note 1)

(e.g. material degradation)

  • credited previous walkdown results, included a description of Yes current action(s) to verify the present equipment condition (e.g.,

walk-bys), meeting the intent of the guidance The licensee:

  • described the conditions of structural items considered for the interim evaluation, including:

o spatial interactions (i.e. interaction between block walls and Yes other items/components) o anchorage Yes o piping connected to tanks (i.e. differential movement Yes between pipes and tanks at connections)

Notes from the Reviewer:

1. The ESEP report does not specifically describe any adverse material condition as a result of the walkdowns and walk-bys. The licensee was requested to describe if and 4

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2 how the material degradation conditions were considered and evaluated for the ESEP.

In its response dated June 23, 2015 (ML15175A457), the licensee clarified that two material degradation conditions were found, namely two similar electrical terminal boxes mounted to short, structural racks that had some rust. The licensee notes that the evaluation and reported HCLPF for these components and their anchorage were based on their unrepaired rusted condition. Furthermore, work orders were already in place to correct the problem. Based on the sufficient reported HCLPF for these components, the staff finds this condition acceptable for the purposes of this interim evaluation.

Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies were identified.

The licensee reported deviations for Catawba Nuclear Station. No If deviations were identified, there is a discussion of how the deficiencies N/A were or will be addressed in the ESEP submittal report.

The NRC staff concludes that:

  • the licensee described the performed walkdown approach, Yes including any credited previous efforts (e.g., Individual Plant Examination of External Events (IPEEE)) consistent with the guidance N/A
  • the licensee addressed identified deviations consistent with the guidance, if any V. Capacity Screening Approach and HCLPF Calculation Results The licensee:
  • described the capacity screening process for the ESEL items, Yes (see notes consistent with the guidance (e.g., use of EPRI NP-6041 screening 1 and 2) table).
  • presented the results of the screened-out ESEL items in the ESEP Yes report
  • described the development of in-structure response spectra (ISRS) Yes based on scaling
  • described the development of ISRS based on new analysis N/A consistent with the guidance
  • described the method for estimating HCLPF capacity of screened- Yes in ESEL items, including both structural and functional failure modes consistent with the guidance:

o use of Conservative Deterministic Failure Margin (CDFM) Yes o use of fragility analysis (FA) N/A o use of experience data or generic information N/A

  • credited IPEEE spectral shape for HCLPF capacity estimates is Yes similar to or envelopes the RLGM, and anchored at the same control point
  • presented the results of HCLPF capacities including associated Yes failure modes for screened-in ESEL items Yes
  • reviewed the ESEL items with the lowest HCLPF values to ensure that their capacities are equal or greater than the RLGM Notes from the Reviewer:

5

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2

1. The ESEP report does not specifically address screening criteria for ESEL items mounted more than 40 ft above grade, nor did the report explicitly establish the elevation of the effective grade, or its relation to the components. The licensee was requested to provide clarification regarding how these items were screened, and a clarification of the defined grade level. In a presentation from the licensee on June 9, 2015, which was attached to the report for the subsequent audit on September 15, 2015 (ML15344A183), the licensee provided clarification that effective grade was defined at the base of the building. All components above the foundation level, whether above or below 40 ft above grade, were screened using guidance typically used only for components mounted above 40 ft above grade. This screening criteria uses 1.5 times the EPRI 6041 basic screening levels (0.8g/1.2g) for comparison to ISRS. This alternate approach for elevations below 40 ft above grade is described EPRI 6041, and is acceptable to the staff for the purposes of this interim evaluation on the basis that the licensees screening results for elevations below 40 ft above grade are consistent with screening results that would be obtained following the EPRI ESEP guidance for screening below 40 ft above grade.
2. Through a series of clarifying questions and responses, the staff also identified that raw narrow-banded ISRS were used in lieu of the design-basis broadened ISRS, that the peaks were clipped, and that the North-South and East-West clipped peaks were averaged. The reduction effect of peak clipping on narrow-banded ISRS is significantly greater than the effect on broadened ISRS; and averaging the ISRS peak accelerations further reduces the numerical value that is used for screening. In a presentation by the licensee on June 9, 2015, which was attached to the report for the subsequent audit on September 15, 2015 (ML15344A183), the licensee presented examples that demonstrated to the staff that the conclusions reached by using the licensees methodology are equivalent to the conclusions that would be reached using the EPRI evaluation guidance. The staff finds that the licensee has sufficiently demonstrated the acceptability of their screening results for the purposes of this interim evaluation.

Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies were identified The NRC staff concludes that:

  • the licensee described the implementation of the capacity Yes screening process consistent with the intent of the guidance
  • the licensee presented capacity screening and calculation results, Yes as appropriate, in the ESEP report
  • the method used to develop the ISRS is consistent with guidance Yes for use in the ESEP
  • for HCLPF calculations, the licensee used HCLPF calculation Yes methods as endorsed in the guidance
  • no anomalies were noted in the reported HCLPF Yes VI. Inaccessible Items The licensee:
  • provided a list of inaccessible items Yes
  • provided a schedule of the planned walkdown and evaluation for all Yes inaccessible items 6

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2

  • provided Regulatory Commitment to complete walkdowns. Yes Catawba will provide results or complete walkdown by:

Within 60 days of the completion of ESEP activities, expected no later than the end of the second refueling outage after December 31, 2014.

Notes from the Reviewer:

1. Three inaccessible hydrogen igniters inside Unit 1 were judged seismically adequate based on similarity with other ones that were accessible for walkdowns.
2. Due to inaccessibility, 38 components of Unit 2 have yet to be evaluated with walkdowns and walkbys. The licensee scheduled to review these items in March 2015.

Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies were identified.

The NRC staff concludes that the licensee:

  • listed inaccessible items Yes
  • committed to provide the results (e.g. walkdowns, walkbys, etc) of Yes the remaining inaccessible items consistent with the guidance
  • substitutions, if needed, were appropriately justified Yes VII. Modifications to Plant Equipment The licensee:
  • identified modifications for ESEL items necessary to achieve Yes HCLPF values that bound the RLGM (excluding mitigative strategies equipment (FLEX)), as specified in the guidance
  • provided a schedule to implement such modifications (if any), Yes consistent with the intent of the guidance
  • provided Regulatory Commitment to complete modifications Yes
  • provided Regulatory Commitment to report completion of Yes modifications.

Catawba will:

  • complete modifications by no later than the end of the second planned refueling outage for each unit after December 31, 2014.
  • report completion of modifications within 60 days following completion of ESEP activities.

Notes from the Reviewer:

None Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies were identified.

The NRC staff concludes that the licensee:

  • identified plant modifications necessary to achieve the target Yes seismic capacity
  • provided a schedule to implement the modifications (if any) Yes consistent with the guidance 7

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2 VIII. General

Conclusions:

The NRC staff assessed the licensees implementation of the ESEP guidance. Due to the interim applicability of the ESEP evaluations, use of the information for another application would require a separate NRC review and approval. Based on its review, the NRC staff concludes that the licensees implementation of the interim evaluation meets the intent of the guidance. The staff concludes that, through the implementation of the ESEP guidance, the licensee identified and evaluated the seismic capacity of certain key installed Mitigating Strategies equipment that is used for core cooling and containment functions to cope with scenarios that involve a loss of all AC power and loss of access to the ultimate heat sink to withstand a seismic event up to the Review Level Ground Motion (RLGM) and thus, provides additional assurance while the plant seismic risk evaluation is being conducted. In the case of Catawba , the RLGM was set at a ratio of 1.91 times the SSE in accordance with the guidance.

The staff did not identify deviations or exceptions taken from the guidance. The application of this staff review is limited to the ESEP interim evaluation as part of NTTF R2.1: Seismic activities. The licensee identified safety enhancing modifications based on the evaluation and committed to complete modifications by within two planned refueling outages after December 31, 2014 and report the completion of modifications within 60 days following completion of ESEP activities. In accordance with the guidance, modifications are expected to be completed no later than December 2016, if the modifications do not require a plant shutdown to access equipment.

In summary, the licensee, by implementing the ESEP interim evaluation, has demonstrated additional assurance which supports continued plant safety while the longer-term seismic evaluation is completed to support regulatory decision making. The NRC staff concludes that the licensee responded appropriately to Enclosure 1, Item (6) of the 50.54(f) letter, dated March 12, 2012, for Catawba Nuclear Station, Units 1 and 2.

Principal Contributors: Dennis Andrukat, On Yee, George Wang, Ian Tseng, Lisa Schleicher, Richard, Rivera-Lugo, Nikolaos Simos (NRC Consultant) 8

NRR-PMDAPEm Resource From: McCoppin, Michael Sent: Wednesday, March 09, 2016 8:13 AM To: Shams, Mohamed; Wyman, Stephen Cc: DiFrancesco, Nicholas; Spence, Jane; Devlin-Gill, Stephanie; Patterson, Eric; Le, Tuan; Heeszel, David; Yee, On; Rivera-Lugo, Richard; Tseng, Ian; 50.54f_Seismic Resource; RidsNroDsea Resource; Andrukat, Dennis; Schleicher, Lisa

Subject:

Catawba ESEP Checklist Attachments: Catawba R2 1 ESEP Review Final IHT 030816_Revised.docx March 4, 2016 MEMORANDUM TO: Mohamed K. Shams, Chief Hazards Management Branch (JHMB)

Japan Lessons-Learned Division Office of Nuclear Reactor Regulation FROM: Michael McCoppin, Chief Geosciences and Geotechnical Engineering Branch 2 (RGS2)

Division of Site Safety and Environmental Analysis Office of New Reactors

SUBJECT:

CATAWBA NUCLEAR STATION, UNITS 1 AND 2- TECHNICAL REVIEW CHECKLIST RELATED TO INTERIM EXPEDITED SEISMIC EVALUATION PROCESS SUPPORTING IMPLEMENTATION OF NTTF RECOMMENDATION 2.1, SEISMIC, RELATED TO THE FUKUSHIMA DAI-ICHI NUCLEAR POWER PLANT ACCIDENT (TAC NO. MF5233, and MF5234)

The NRC technical staff working through the Geosciences and Geotechnical Engineering Branches 1 and 2 (RGS1 and RGS2) completed the Technical Review Checklist of the CATAWBA NUCLEAR STATION, UNITS 1 AND 2 response to Enclosure 1, Item (6) of the March 12, 2012, request for information letter issued per Title 10 of the Code of Federal Regulations, Subpart 50.54(f), to power reactor licensees and holders of construction permits requesting addressees to provide further information to support the NRC staffs evaluation of regulatory actions to be taken in response to Fukushima Near-Term Task Force (NTTF) Recommendation 2.1: Seismic which implements lessons learned from Japans March 11, 2011, Great Thoku Earthquake and subsequent tsunami. The addresses the staff review of the interim Expedited Seismic Evaluation Process (ESEP) report in response to Requested Item (6) of Enclosure 1, Recommendation 2.1: Seismic, of the 50.54(f) letter. Attached is a file containing the technical review checklist to prepare a response letter to the licensee.

The NRC staff reviewed the information provided and, as documented in the enclosed staff checklist, determined that sufficient information was provided to be responsive to this portion of the Enclosure 1 of the 50.54(f) letter. The application of this staff review is limited to the interim ESEP as part of NTTF R2.1: Seismic activities.

This electronic memo constitutes the DSEA concurrence provided that only editorial changes are made to the staff assessment that would not affect the technical conclusions or technical context of the assessment.

This concludes the NRCs efforts associated with TAC NO. MF5233 and MF5234 for the review of the interim ESEP report for the CATAWBA NUCLEAR STATION, UNITS 1 AND 2.

1

Docket No: 50-413 and 50-414 CONTACT: Stephanie Devlin-Gill Office of New Reactors 301-415-5301 Copy: Nicholas DiFrancesco, Steve Wyman, Jane Spence, Stephanie Devlin-Gill, Dennis Andrukat, On Yee, George Wang, Ian Tseng, Lisa Schleicher, Richard, Rivera-Lugo, Nikolaos Simos, (NRC Consultant) , 50.54f Seismic Resource, RidsNroDsea Resource Mike McCoppin, MBA, PMP Branch Chief, Radiation Protection &

Accident Consequences (RPAC)

Office of New Reactors United States Nuclear Regulatory Commission Mail Stop: T7-F03 Office: T7-F18 Ph: 301.415.6533 Cell: 202.731.1423 FAX: 301.415.5399 Email:michael.mccoppin@nrc.gov CONFIDENTIALITY NOTICE: This electronic message is intended to be viewed only by the individual or entity to whom it is addressed. It may contain information that is privileged, confidential and exempt from disclosure under applicable law. Any dissemination, distribution or copying of this communication is strictly prohibited without prior permission. If the reader of this message is not the intended recipient, or the employee or agent responsible for delivering the message to the intended recipient, or if you have received this communication in error, please notify me immediately by return e-mail and delete the original message and any copies of it from your computer system.

2

Hearing Identifier: NRR_PMDA Email Number: 2695 Mail Envelope Properties (7e0f4063a5584db5a518613429409292)

Subject:

Catawba ESEP Checklist Sent Date: 3/9/2016 8:12:30 AM Received Date: 3/9/2016 8:12:31 AM From: McCoppin, Michael Created By: Michael.McCoppin@nrc.gov Recipients:

"DiFrancesco, Nicholas" <Nicholas.DiFrancesco@nrc.gov>

Tracking Status: None "Spence, Jane" <Jane.Spence@nrc.gov>

Tracking Status: None "Devlin-Gill, Stephanie" <Stephanie.Devlin-Gill@nrc.gov>

Tracking Status: None "Patterson, Eric" <Eric.Patterson@nrc.gov>

Tracking Status: None "Le, Tuan" <Tuan.Le@nrc.gov>

Tracking Status: None "Heeszel, David" <David.Heeszel@nrc.gov>

Tracking Status: None "Yee, On" <On.Yee@nrc.gov>

Tracking Status: None "Rivera-Lugo, Richard" <Richard.Rivera-Lugo@nrc.gov>

Tracking Status: None "Tseng, Ian" <Ian.Tseng@nrc.gov>

Tracking Status: None "50.54f_Seismic Resource" <50.54f_Seismic.Resource@nrc.gov>

Tracking Status: None "RidsNroDsea Resource" <RidsNroDsea.Resource@nrc.gov>

Tracking Status: None "Andrukat, Dennis" <Dennis.Andrukat@nrc.gov>

Tracking Status: None "Schleicher, Lisa" <Lisa.Schleicher@nrc.gov>

Tracking Status: None "Shams, Mohamed" <Mohamed.Shams@nrc.gov>

Tracking Status: None "Wyman, Stephen" <Stephen.Wyman@nrc.gov>

Tracking Status: None Post Office: HQPWMSMRS07.nrc.gov Files Size Date & Time MESSAGE 3726 3/9/2016 8:12:31 AM Catawba R2 1 ESEP Review Final IHT 030816_Revised.docx 58579 Options Priority: Standard Return Notification: No Reply Requested: No

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TECHNICAL REVIEW CHECKLIST BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO EXPEDITED SEISMIC EVALUATION PROCESS INTERIM EVALUATION IMPLEMENTING NTTF RECOMMENDATION 2.1 SEISMIC CATAWBA NUCLEAR STATION, UNITS 1 AND 2 DOCKET NOS. 50-413 AND 50-414 By letter dated March 12, 2012 (USNRC, 2012a), the U.S. Nuclear Regulatory Commission (NRC) issued a request for information to all power reactor licensees and holders of construction permits in active or deferred status, pursuant to Title 10 of the Code of Federal Regulations (10 CFR), Section 50.54(f) Conditions of License (hereafter referred to as the 50.54(f) letter). Enclosure 1 of the 50.54(f) letter requests addressees to reevaluate the seismic hazard at their site using present-day methods and guidance for licensing new nuclear power plants, and identify actions to address or modify, as necessary, plant components affected with the reevaluated seismic hazards. Requested Information Item (6) in Enclosure 1 to the 50.54(f) letter requests addressees to provide an interim evaluation and actions taken or planned to address a higher seismic hazard relative to the design basis, as appropriate, prior to completion and submission of the seismic risk evaluation.

Additionally, by letter dated April 12, 20131, the Electric Power Research Institute (EPRI) staff submitted EPRI TR 3002000704 Seismic Evaluation Guidance: Augmented Approach for the Resolution of Fukushima Near-Term Task Force (NTTF) Recommendation 2.1: Seismic (hereafter referred to as the guidance). The Augmented Approach proposed that licensees would use an Expedited Seismic Evaluation Process (ESEP) to address the interim actions as requested by Information Item (6) in the 50.54(f) letter. The ESEP is a simplified seismic capacity evaluation with a focused scope of certain key installed Mitigating Strategies equipment that is used for core cooling and containment functions to cope with scenarios that involve a loss of all AC power and loss of access to the ultimate heat sink to withstand the Review Level Ground Motion, which is up to two times the safe shutdown earthquake (SSE).

Due to the expedited and interim nature of the ESEP, the assessment does not include many considerations that are part of a normal risk evaluation. These deferred items, include but are not limited to, structures, piping, non-seismic failures, and operator actions, as well scenarios such as addressing loss of coolant accidents. By letter dated May 7, 20132, the NRC staff endorsed the guidance. Central and eastern United States licensees with a reevaluated seismic hazard exceeding the SSE submitted an ESEP interim evaluation in December 2014.

Consistent with the interim nature of this activity, the staff performed the review of the licensees submittal to assess whether the intent of the guidance was implemented. A multi-disciplined team checked whether the identified methods were consistent with the guidance. A senior expert panel reviewed the teams questions, if any, and checklist for consistency and scope.

New or updated parameters (e.g., In-Structure Response Spectra, High Confidence of Low Probability of Failure calculations) presented by the licensees were assessed only based on licensee statements for acceptability for the Item (6) response. The application of this staff review is limited to the ESEP interim evaluation as part of NTTF R2.1: Seismic activities.

1 ADAMS Accession No. ML13102A142 2 ADAMS Accession No. ML13106A331

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2 By letter dated December 31, 2014,3 Duke Energy Carolina, LLC (the licensee) provided an Expedited Seismic Evaluation Process (ESEP) report in a response to Enclosure 1, Requested Information Item (6) of the 50.54(f) letter, for the Catawba Nuclear Station, Units 1 and 2 (Catawba).

I. Review Level Ground Motion The licensee:

  • described the determination of the review level ground motion Yes (RLGM) using one of the means acceptable by the guidance (see Note 1) Yes
  • identified location of the control point and is consistent with March 2014 Seismic Hazard and Screening Report4 submittal Yes
  • compared the site ground motion response spectra used to select the ESEP RLGM to the SSE.

Catawba used a scaled SSE at a ratio of 1.91 at 10 Hz Notes from the Reviewer:

1. The licensee did not provide the SSE with all of the values used to calculate the RLGM. However, using the information in Figure 4-3, the staff was able to generally reproduce the licensees RLGM when using the SSE information digitized from Figure 4-3 rather than the information in Table 4-1 of the ESEP. This is acceptable for the purposes of this interim evaluation.

Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies were identified.

The NRC staff concludes:

  • the licensees RLGM meets the intent of the guidance Yes
  • the RLGM is reasonable for use in the interim evaluation. Yes II. Selection of the Success Path The licensee:
  • described the success path Yes
  • described normal and desired state of the equipment for the Yes success path
  • ensured that the success path is consistent with the plants overall Yes mitigating strategies approach or provided a justification for an alternate path
  • stated that the selection process was in accordance with the Yes guidance or meets the intent of the guidance
  • used installed FLEX Phase 1 equipment as part of the success Yes path
  • included FLEX Phase 2 and/or 3 connections Yes

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2 Notes from the Reviewer:

None Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies identified.

The NRC staff concludes that:

  • the selected success path is reasonable for use in the interim evaluation Yes
  • the licensee considered installed Phase 2 and 3 connections or equipment in the interim evaluation. Yes III. Selection of the Equipment List The licensee:
  • developed and provided the ESEL by applying the ESEP Yes
  • identified equipment considering the following functions:

o Core cooling (with focus on Mode 1) function Yes o Available, sustainable water source Yes o Containment function and integrity Yes Notes from the Reviewer:

None Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies identified.

For PWR Plants ONLY The licensee included indicators / instrumentation for the following functions: level, pressure, temperature, that would be indicative of (but not Yes explicitly identified to specific instruments): water level of the steam generator (SG), pressure of SG, containment, and reactor coolant system (RCS); and temperature of the RCS.

For BWR Plants ONLY The licensee considered indicators for the following functions:

level, pressure, temperature that would be indicative of (but not explicitly N/A identified to specific instruments): Temperature of suppression pool, RCS, containment); Pressure of suppression pool, RCS, and drywell; water level of the suppression pool.

Notes from the Reviewer:

None Deviation(s) or Deficiency(ies), and Consequence(s):

No deviations or deficiencies identified.

3

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2 Through a sampling of the ESEP key components, the NRC staff concludes that:

  • the licensees process to develop the ESEL meets the intent of the Yes guidance for the interim evaluation
  • the desired equipment state for the success path were identified Yes
  • the licensee considered the support equipment for the ESEL Yes
  • both front-line and support systems appeared to be included in the Yes ESEL as evidenced by inclusion of SSCs on the success path and of support systems (e.g., batteries, motor control centers, inverters).

IV. Walkdown Approach The licensee:

  • described the walkdown screening approach, including walkbys Yes and walkdowns performed exclusively for the ESEP, in accordance with the guidance
  • credited previous walkdown results, including a description of Yes current action(s) to verify the present equipment condition and/or configuration (e.g., walk-bys), in accordance with the guidance
  • stated that the walkdown was performed by seismically trained Yes personnel Notes from the Reviewer:
1. The licensee stated that credit was given to the previous walkdowns since these walkdowns were performed by qualified Seismic Review Teams, but they do not state the qualifications of the ESEP Seismic Review Team. The licensee was requested to provide more information on the qualification of the personnel that performed the plant seismic walkdowns. In its response, dated June 23, 2015 (ML15175A457), the licensee provided information on the ESEP Seismic Review Team members, which sufficiently demonstrates their training and qualification levels.

Deviation(s) or Deficiency(ies), and Resolution:

The reviewer did not find any deviations or deficiencies.

The licensee:

  • described, as needed, adverse material condition of the equipment Yes (see note 1)

(e.g. material degradation)

  • credited previous walkdown results, included a description of Yes current action(s) to verify the present equipment condition (e.g.,

walk-bys), meeting the intent of the guidance The licensee:

  • described the conditions of structural items considered for the interim evaluation, including:

o spatial interactions (i.e. interaction between block walls and Yes other items/components) o anchorage Yes o piping connected to tanks (i.e. differential movement Yes between pipes and tanks at connections)

Notes from the Reviewer:

1. The ESEP report does not specifically describe any adverse material condition as a result of the walkdowns and walk-bys. The licensee was requested to describe if and 4

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2 how the material degradation conditions were considered and evaluated for the ESEP.

In its response dated June 23, 2015 (ML15175A457), the licensee clarified that two material degradation conditions were found, namely two similar electrical terminal boxes mounted to short, structural racks that had some rust. The licensee notes that the evaluation and reported HCLPF for these components and their anchorage were based on their unrepaired rusted condition. Furthermore, work orders were already in place to correct the problem. Based on the sufficient reported HCLPF for these components, the staff finds this condition acceptable for the purposes of this interim evaluation.

Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies were identified.

The licensee reported deviations for Catawba Nuclear Station. No If deviations were identified, there is a discussion of how the deficiencies N/A were or will be addressed in the ESEP submittal report.

The NRC staff concludes that:

  • the licensee described the performed walkdown approach, Yes including any credited previous efforts (e.g., Individual Plant Examination of External Events (IPEEE)) consistent with the guidance N/A
  • the licensee addressed identified deviations consistent with the guidance, if any V. Capacity Screening Approach and HCLPF Calculation Results The licensee:
  • described the capacity screening process for the ESEL items, Yes (see notes consistent with the guidance (e.g., use of EPRI NP-6041 screening 1 and 2) table).
  • presented the results of the screened-out ESEL items in the ESEP Yes report
  • described the development of in-structure response spectra (ISRS) Yes based on scaling
  • described the development of ISRS based on new analysis N/A consistent with the guidance
  • described the method for estimating HCLPF capacity of screened- Yes in ESEL items, including both structural and functional failure modes consistent with the guidance:

o use of Conservative Deterministic Failure Margin (CDFM) Yes o use of fragility analysis (FA) N/A o use of experience data or generic information N/A

  • credited IPEEE spectral shape for HCLPF capacity estimates is Yes similar to or envelopes the RLGM, and anchored at the same control point
  • presented the results of HCLPF capacities including associated Yes failure modes for screened-in ESEL items Yes
  • reviewed the ESEL items with the lowest HCLPF values to ensure that their capacities are equal or greater than the RLGM Notes from the Reviewer:

5

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2

1. The ESEP report does not specifically address screening criteria for ESEL items mounted more than 40 ft above grade, nor did the report explicitly establish the elevation of the effective grade, or its relation to the components. The licensee was requested to provide clarification regarding how these items were screened, and a clarification of the defined grade level. In a presentation from the licensee on June 9, 2015, which was attached to the report for the subsequent audit on September 15, 2015 (ML15344A183), the licensee provided clarification that effective grade was defined at the base of the building. All components above the foundation level, whether above or below 40 ft above grade, were screened using guidance typically used only for components mounted above 40 ft above grade. This screening criteria uses 1.5 times the EPRI 6041 basic screening levels (0.8g/1.2g) for comparison to ISRS. This alternate approach for elevations below 40 ft above grade is described EPRI 6041, and is acceptable to the staff for the purposes of this interim evaluation on the basis that the licensees screening results for elevations below 40 ft above grade are consistent with screening results that would be obtained following the EPRI ESEP guidance for screening below 40 ft above grade.
2. Through a series of clarifying questions and responses, the staff also identified that raw narrow-banded ISRS were used in lieu of the design-basis broadened ISRS, that the peaks were clipped, and that the North-South and East-West clipped peaks were averaged. The reduction effect of peak clipping on narrow-banded ISRS is significantly greater than the effect on broadened ISRS; and averaging the ISRS peak accelerations further reduces the numerical value that is used for screening. In a presentation by the licensee on June 9, 2015, which was attached to the report for the subsequent audit on September 15, 2015 (ML15344A183), the licensee presented examples that demonstrated to the staff that the conclusions reached by using the licensees methodology are equivalent to the conclusions that would be reached using the EPRI evaluation guidance. The staff finds that the licensee has sufficiently demonstrated the acceptability of their screening results for the purposes of this interim evaluation.

Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies were identified The NRC staff concludes that:

  • the licensee described the implementation of the capacity Yes screening process consistent with the intent of the guidance
  • the licensee presented capacity screening and calculation results, Yes as appropriate, in the ESEP report
  • the method used to develop the ISRS is consistent with guidance Yes for use in the ESEP
  • for HCLPF calculations, the licensee used HCLPF calculation Yes methods as endorsed in the guidance
  • no anomalies were noted in the reported HCLPF Yes VI. Inaccessible Items The licensee:
  • provided a list of inaccessible items Yes
  • provided a schedule of the planned walkdown and evaluation for all Yes inaccessible items 6

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2

  • provided Regulatory Commitment to complete walkdowns. Yes Catawba will provide results or complete walkdown by:

Within 60 days of the completion of ESEP activities, expected no later than the end of the second refueling outage after December 31, 2014.

Notes from the Reviewer:

1. Three inaccessible hydrogen igniters inside Unit 1 were judged seismically adequate based on similarity with other ones that were accessible for walkdowns.
2. Due to inaccessibility, 38 components of Unit 2 have yet to be evaluated with walkdowns and walkbys. The licensee scheduled to review these items in March 2015.

Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies were identified.

The NRC staff concludes that the licensee:

  • listed inaccessible items Yes
  • committed to provide the results (e.g. walkdowns, walkbys, etc) of Yes the remaining inaccessible items consistent with the guidance
  • substitutions, if needed, were appropriately justified Yes VII. Modifications to Plant Equipment The licensee:
  • identified modifications for ESEL items necessary to achieve Yes HCLPF values that bound the RLGM (excluding mitigative strategies equipment (FLEX)), as specified in the guidance
  • provided a schedule to implement such modifications (if any), Yes consistent with the intent of the guidance
  • provided Regulatory Commitment to complete modifications Yes
  • provided Regulatory Commitment to report completion of Yes modifications.

Catawba will:

  • complete modifications by no later than the end of the second planned refueling outage for each unit after December 31, 2014.
  • report completion of modifications within 60 days following completion of ESEP activities.

Notes from the Reviewer:

None Deviation(s) or Deficiency(ies), and Resolution:

No deviations or deficiencies were identified.

The NRC staff concludes that the licensee:

  • identified plant modifications necessary to achieve the target Yes seismic capacity
  • provided a schedule to implement the modifications (if any) Yes consistent with the guidance 7

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for Catawba Nuclear Station, Units 1 and 2 VIII. General

Conclusions:

The NRC staff assessed the licensees implementation of the ESEP guidance. Due to the interim applicability of the ESEP evaluations, use of the information for another application would require a separate NRC review and approval. Based on its review, the NRC staff concludes that the licensees implementation of the interim evaluation meets the intent of the guidance. The staff concludes that, through the implementation of the ESEP guidance, the licensee identified and evaluated the seismic capacity of certain key installed Mitigating Strategies equipment that is used for core cooling and containment functions to cope with scenarios that involve a loss of all AC power and loss of access to the ultimate heat sink to withstand a seismic event up to the Review Level Ground Motion (RLGM) and thus, provides additional assurance while the plant seismic risk evaluation is being conducted. In the case of Catawba , the RLGM was set at a ratio of 1.91 times the SSE in accordance with the guidance.

The staff did not identify deviations or exceptions taken from the guidance. The application of this staff review is limited to the ESEP interim evaluation as part of NTTF R2.1: Seismic activities. The licensee identified safety enhancing modifications based on the evaluation and committed to complete modifications by within two planned refueling outages after December 31, 2014 and report the completion of modifications within 60 days following completion of ESEP activities. In accordance with the guidance, modifications are expected to be completed no later than December 2016, if the modifications do not require a plant shutdown to access equipment.

In summary, the licensee, by implementing the ESEP interim evaluation, has demonstrated additional assurance which supports continued plant safety while the longer-term seismic evaluation is completed to support regulatory decision making. The NRC staff concludes that the licensee responded appropriately to Enclosure 1, Item (6) of the 50.54(f) letter, dated March 12, 2012, for Catawba Nuclear Station, Units 1 and 2.

Principal Contributors: Dennis Andrukat, On Yee, George Wang, Ian Tseng, Lisa Schleicher, Richard, Rivera-Lugo, Nikolaos Simos (NRC Consultant) 8

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