ML15281A004

NRR E-mail Capture - Callaway Plant - Technical Review Checklist Related to Interim ESEP Supporting Implementation of NTTF R2.1, Seismic

ML15281A004
Person / Time
Site:	Callaway
Issue date:	10/01/2015
From:	Diane Jackson Office of New Reactors
To:	Mohamed Shams Japan Lessons-Learned Division
References
TAC MF5230
Download: ML15281A004 (12)

Text

NRR-PMDAPEm Resource From: Jackson, Diane Sent: Thursday, October 01, 2015 2:53 PM To: Shams, Mohamed Cc: DiFrancesco, Nicholas; Spence, Jane; Devlin-Gill, Stephanie; Roche, Kevin; Yee, On; Stirewalt, Gerry; Lyons, Sara; Basavaraju, Chakrapani; Graizer, Vladimir; Wyman, Stephen; 50.54f_Seismic Resource; RidsNroDsea Resource

Subject:

CALLAWAY PLANT - TECHNICAL REVIEW CHECKLIST RELATED TO INTERIM ESEP SUPPORTING IMPLEMENTATION OF NTTF R2.1, SEISMIC (TAC NO. MF5230)

Attachments: Callaway R2.1 Seismic ESEP NRC review.docx October 1, 2015 MEMORANDUM TO: Mohamed K. Shams, Chief Hazards Management Branch (JHMB)

Japan Lessons-Learned Division Office of Nuclear Reactor Regulation FROM: Diane T. Jackson, Chief Geosciences and Geotechnical Engineering Branch 2 (RGS2)

Division of Site Safety and Environmental Analysis Office of New Reactors

SUBJECT:

CALLAWAY NUCLEAR STATION - 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. MF5230)

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 CALLAWAY PLANT 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. MF5230 for the review of the interim ESEP report for the CALLAWAY PLANT.

Docket No: 50-483 CONTACT: Stephanie Devlin-Gill Office of New Reactors 301-415-5301 1

Copy: Nicholas DiFrancesco, Steve Wyman, Jane Spence, Stephanie Devlin-Gill, Kevin Roche, On Yee, Gerry Stirewalt, Sara Lyons, BP Jain, Basavaraju Chakrapani, Vladimir Graizer, 50.54f Seismic Resource, RidsNroDsea Resource 2

Hearing Identifier: NRR_PMDA Email Number: 2438 Mail Envelope Properties (1dfe7f1851924ac18c5de196a745c81b)

Subject:

CALLAWAY PLANT - TECHNICAL REVIEW CHECKLIST RELATED TO INTERIM ESEP SUPPORTING IMPLEMENTATION OF NTTF R2.1, SEISMIC (TAC NO. MF5230)

Sent Date: 10/1/2015 2:52:49 PM Received Date: 10/1/2015 2:52:51 PM From: Jackson, Diane Created By: Diane.Jackson@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 "Roche, Kevin" <Kevin.Roche@nrc.gov>

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

Tracking Status: None "Stirewalt, Gerry" <Gerry.Stirewalt@nrc.gov>

Tracking Status: None "Lyons, Sara" <Sara.Lyons@nrc.gov>

Tracking Status: None "Basavaraju, Chakrapani" <Chakrapani.Basavaraju@nrc.gov>

Tracking Status: None "Graizer, Vladimir" <Vladimir.Graizer@nrc.gov>

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

Tracking Status: None Post Office: HQPWMSMRS07.nrc.gov Files Size Date & Time MESSAGE 3014 10/1/2015 2:52:51 PM Callaway R2.1 Seismic ESEP NRC review.docx 53504 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 CALLAWAY PLANT UNIT 1 DOCKET NO. 50-483 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 the Callaway Plant, Unit 1 By letter dated December 22, 2014,3 Ameren Missouri (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 Union Electric Company Callaway Plant, Unit 1 (Callaway).

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

• identified location of the control point and is consistent with March Yes 2014 Seismic Hazard and Screening Report submittal

• compared the site ground motion response spectra used to select Yes the ESEP RLGM to the SSE Callaway used 2 x SSE.

Notes from reviewer:

• The licensee used the maximum ratio of two times the SSE because the GMRS from the March 2014 Seismic Hazard and Screening report (SHSR)4 was greater than two times the SSE for the site, except for three surface mounted items that used the GMRS.

Deviation(s) or Deficiency(ies)s 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

• considered installed FLEX Phase 2 and/or 3 equipment Yes Notes from reviewer: None Deviation(s) or Deficiency(ies)s and Resolution:

• No deviations or deficiencies were identified 3 ADAMS Accession No. ML14363A311 4 ADAMS Accession No. ML14090A448 2

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for the Callaway Plant, Unit 1 The NRC staff concludes that:

• the selected success path is reasonable for use in the interim Yes evaluation

• the licensee considered installed Phase 2 and 3 connections or Yes equipment in the interim evaluation 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 reviewer:

1. In the initial submittal, the licensee did not include many of the components that were needed in the ESEL per the ESEP guidance. However, in the RAI response, the components, including atmospheric relief valves, accumulators, accumulation isolation valves, reactor head vent or pressurizer power operated relief valve, were added to the ESEL per a letter from the licensee dated September 9, 2015 (ML15259A322 and ML15259A323). The staff finds this acceptable for the purpose of this interim evaluation.

2. The licensee committed to installing a new hardened condensate storage tank (HCST), but did not include the HCST in the ESEL. The licensee did not address changes in the flow path resulting from the new HCST. This was a concern to the extent that the new flow path may include components that would fall within the scope of the ESEL. Therefore, the staff requested confirmation whether the HCST and associated SSCs will achieve a HCLPF capacity at the level of the RLGM. In the response dated June 3, 2015 (ML15155A459), the licensee stated that the HCST will achieve a HCLPF capacity at the level of the RLGM and that the air operated valve in the new flow path will be seismically analyzed to meet ESEP requirements. The staff finds this acceptable for the purpose of this interim evaluation.

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

• No deviations or deficiencies were identified.

PWR Plants ONLY The licensee included indicators / instrumentation for the following functions:

Yes level, pressure, temperature, that would be indicative of (but not explicitly identified to specific instruments): water level of the steam generator (SG),

pressure of SG, containment, and RCS; and temperature of the RCS.

BWR Plants ONLY The licensee considered indicators for the following functions: level, pressure, temperature that would be indicative of, but not explicitly identified N/A with, specific instruments: Temperature of suppression pool, RCS, containment; pressure of suppression pool, RCS, and drywell; water level of the suppression pool.

3

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for the Callaway Plant, Unit 1 Notes from reviewer:

1. In the initial submittal, all necessary instrumentation did not appear to be included in ESEL. The staff asked the licensee to confirm that instrumentation for the following SSCs are included in, or will be added to, the ESEL: (a) SG water level, (b) SG pressure, (c) containment pressure, (d) RCS pressure, (e) RCS temperature. In a letter response dated September 9, 2015 (ML15259A322 and ML15259A323), the licensee added all necessary instrumentation to the ESEL and included a regulatory commitment to perform associated walkdowns, HCLPF updates, report required modifications, and report this information to the NRC. The staff finds that the responses adequately addressed the question and met the intent of the guidance for this interim evaluation.

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

• No deviations or deficiencies were identified.

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 ESEL as evidenced by inclusion of SSCs on the success path and of Yes 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 No personnel Notes from reviewer:

1. The licensee did not initially indicate that seismic walkdown personnel were trained in seismic walkdown procedures. The staff requested confirmation that the walkdowns were conducted by personnel who had successfully completed training specific for seismic walkdown procedures. In an email response dated June 3, 2015 (ML15155A459), the licensee confirmed that walkdown personnel were properly trained in seismic walkdown procedures. The staff finds that the response adequately addressed the question and met the intent of the guidance for this interim evaluation.

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

• No deviations or deficiencies were identified.

4

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for the Callaway Plant, Unit 1 The licensee:

• described adverse material condition of the equipment No (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 reviewer:

1. The licensee did not describe adverse material condition of any equipment because no adverse material conditions were found during the walkdown, so this item is no.

The staff finds this acceptable for the purpose of this interim evaluation.

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

No deviations or deficiencies were identified The licensee reported no deviations for Callaway 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

• the licensee addressed identified deviations consistent with the guidance, if any Yes V. Capacity Screening Approach and HCLPF Calculation Results The licensee:

• described the capacity screening process for the ESEL items, Yes consistent with the guidance (e.g., use of EPRI NP-6041 screening table). Yes

• presented the results of the screened-out ESEL items in the ESEP report. Yes

• described the development of in-structure response spectra (ISRS) 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-in ESEL items, including both structural and functional failure modes Yes consistent with the guidance:

o use of Conservative Deterministic Failure Margin (CDFM) Yes (CDFM) o use of fragility analysis (FA) N/A 5

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for the Callaway Plant, Unit 1 o use of experience data or generic information N/A

• credited IPEEE spectral shape for HCLPF capacity estimates is similar to or envelopes the RLGM, and anchored at the same control N/A point

• presented the results of HCLPF capacities including associated Yes failure modes for screened-in ESEL items

• reviewed the ESEL items with the lowest HCLPF values to ensure that their capacities are equal or greater than the RLGM Yes Notes from reviewer: None 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 screening Yes process consistent with the intent of the guidance

• the licensee presented capacity screening and calculation results, as Yes appropriate, in the ESEP report

• the method used to develop the ISRS is consistent with guidance for Yes 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

• provided Regulatory Commitment to complete walkdowns Yes Callaway will complete walkdowns and evaluations and provide results by no later than 60 days following completion of Refueling Outage 21, Spring 2016.

6

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for the Callaway Plant, Unit 1 Notes from reviewer:

1. In the original ESEP Section 7.1, the licensee stated that sufficient access was provided for all ESEL items and no additional walkdowns are planned. By letter dated September 9, 2015 (ML15259A322 and ML15259A323), the licensee provided a list of additional ESEL items, a schedule to walkdown the items and perform HCLPF table updates, report any required modifications with proposed completion dates, and to provide a letter with this supplemental information to the NRC no later than 60 days following completion of Refueling Outage 21, Spring 2016.

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

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

• listed inaccessible items N/A

• committed to provide the results (e.g., walkdowns, walkbys, etc.) of N/A the remaining inaccessible items consistent with the guidance

• substitutions, if needed, were appropriately justified N/A VII. Modifications to Plant Equipment The licensee:

• identified modifications for ESEL items necessary to achieve HCLPF Yes 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 Callaway will

• Complete modifications by: December 31, 2016 for modifications not requiring a planned refueling outage, and within two planned refueling outages after December 31, 2016 for modifications requiring a refueling outage.

• Report completion of all ESEP modifications by: Not later than 60 days following completion of any required modifications, and not later than 60 days following completion of Refueling Outage 22, Fall 2017.

Notes from 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 seismic Yes capacity

• provided a schedule to implement the modifications (if any) consistent with the guidance Yes 7

NTTF Recommendation 2.1 Expedited Seismic Evaluation Process Technical Review Checklist for the Callaway Plant, Unit 1 VIII. 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 Callaway, the RLGM was set at the maximum ratio of two times the SSE in accordance with the guidance because the GMRS is above two times the SSE, except for three surface mounted items that used the GMRS. The application of this staff review is limited to the ESEP interim evaluation as part of NTTF R2.1: Seismic activities. As noted in the review checklist, the staff did not identify deviations or exceptions were taken from the guidance. The licensee will complete currently identified modifications by December 31, 2016, for modifications not requiring a planned refueling outage. The licensee committed to provide a letter with supplemental information regarding the evaluation results of the additional ESEL items to the NRC no later than 60 days following completion of Refueling Outage 21, Spring 2016.

Modifications requiring a refueling outage will be completed within two planned refueling outages after December 31 2016. The licensee committed to report completion of all ESEP modifications not later than 60 days following completion of the modifications, and not later than 60 days following completion of Refueling Outage 22, Fall 2017.

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 Callaway Plant, Unit 1.

Principal Contributors: Vladimir Graizer, Kevin Roche, Sara Lyons, Jinsuo Nie, B.P. Jain, Basavaraju Chakrapani, Kaihwa Hsu, Gerry Stirewalt, Carl Costantino (NRC Consultant) 8