ML14113A555

Draft Staff Assessment of Seismic Walkdown Report Near-term Task Force Recommendation 2.3 Related to the Fukushima DAI-ICHI Nuclear Power Plant Accident; PPL Susquehanna, LLC; Susquehanna Steam Electric Station, Unit 1. Docket No. 50-387

ML14113A555
Person / Time
Site:	Susquehanna
Issue date:	04/23/2014
From:	Jeffrey Whited Plant Licensing Branch 1
To:
Whited J, NRR/DORL/LPLI-2
References
Download: ML14113A555 (18)

Text

OFFICIAL USE ONLY SECURITY RELATED INFORMATION ~~I'(

DRAFT STAFF ASSESSMENT OF SEISMIC WALKDOWN REPORT NEAR-TERM TASK FORCE RECOMMENDATION 2.3 RELATED TO THE FUKUSHIMA DAI-ICHI NUCLEAR POWER PLANT ACCIDENT PPL SUSQUEHANNA, LLC SUSQUEHANNA STEAM ELECTRIC STATION UNIT 1 DOCKET NO. 50-387

1.0 INTRODUCTION

~n Mar~h 12, 20~2, 1 the U.S. Nuclear Regulatory C '*\;~:~ion (NRC) isstl\e~~ request for mformat1on per T1tle 10 of the Code of Federal Re . ns, Subpart 50.54(f) (~.54(f) letter) to all power reactor licensees and holders of cons~n permits iQ. active or defe~ status. The request was part of the implementation of lesson

• ned fro. **

• accident at thei'ftJkushima Dai-ichi nuclear power plant. Enclosure 3, "Recom* . ati  : Seismic," 2 to the 50.54(f) letter requested licensees to conduct seismic walkdov.~R$,fpli,dentify and address degraded, nonconforming, or unanalyzed conditi~~ing the corre action program (CAP), verify the adequacy of monitoring and maintena~~ures, and' rt the results to the NRC. of the 50.54(f) letter requesteH*ucen~~~*.provid:*:~following:

a. Information c9 .* e plant~~ hazard licensing bases and a description of the protecijprtllnd mitig *. n featur¥:tonsidered in the licensing basis evaluation.

b. Information .related to -~';im~lementatiM of the walkdown process.

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c. A list of plant-spe<;ifjc vulnerabilities .;.:*('identified by the IPEEE [Individual Plant Examinationof EXtern~ I Events] and a description of the actions taken to eliminate or reduce then'L ..

d. Results of the wii_l~down including key findings and identified degraded, nonconforming, dti':inanalyzed conditions ...

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e. Any planned ot~ly installed protection and mitigation features.

f. Results and any subsequent actions taken in response to the peer review.

In accordance with the 50.54(f) letter, Enclosure 3, Required Response Item 2, licensees were required to submit a response within 180 days of the NRC's endorsement of the seismic walkdown process. By letter dated May 29, 2012, 3 the Nuclear Energy Institute (NEI) staff submitted Electric Power Research Institute (EPRI) document 1025286, "Seismic Walkdown 1 Agencywide Documents Access and Management System (ADAMS) Accession No. ML12053A340.

2 ADAMS Accession No. ML12056A049.

3 ADAMS Package Accession No. ML121640872.

Enclosure 1 DRAFT OFFICIAL USE ONLY SECURITY RELATED INFORMATION G'Aw

OFFICIAL USE ONLY SECURITY RELATED INFORMATION Guidance for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Seismic,"

(walkdown guidance) for the NRC staff to consider for endorsement. By letter dated May 31, 2012, 4 the NRC staff endorsed the walkdown guidance.

By letter dated November 26, 2012, 5 PPL Susquehanna, LLC (PPL, or the licensee) provided a response to Enclosure 3 of the 50.54(f) letter Required Response Item 2, for Susquehanna Steam Electric Station Unit 1 (SSES-1 ). The NRC staff reviewed the walkdown report and determined that additional supplemental information would assist the staff in completing its review. In a letter dated November 1, 2013, 6 the NRC requested ad

• I information to gain a better understanding of the processes and procedures used by in conducting the walkdowns and walk-bys. The licensee responded to the NRC by letter dated November 27, 2013. 7 The NRC staff evaluated the licensee's submittals to d *on provided in the walkdown report met the intent of the walkdown guid ponded appropriately to Enclosure 3 of the 50.54(f) letter.

2.0 REGULATORY EVALUATION

The structures, systems, and components (SSCs) in operating nuclear power plants are designed either in with, e intent of Appendix A to 10 CFR Part 50, "General Design nts," Criterion 2: "Design bases for protection against natural ph ... nn,rn ... l CFR Part 100, "Reactor Site Criteria." Criterion 2 states that SSCs i r plants shall be designed to withstand the of natu uakes, tornadoes, hurricanes, floods, tsun hes to perform their safety functions.

For initial licensing, op and maintain design bases that, as defined by 10 CFR that an sse of a facility must perform, and the specific values r controlling parameters as reference bounds for the d~n.

The design bases for the bases alscueflect sufficie time in which the historical d.

phenomena that have oet:Ul'.~JCJI::>It;;,r rgin for the limited accuracy, quantity, and period of have been accumulated.

The current licensing basis is the set of NRC requirements applicable to a specific plant, including the licensee's docketed commitments for ensuring compliance with, and operation within, applicable NRC requirements and the plant-specific design basis, including all modifications and additions to such commitments over the life of the facility operating license.

4 ADAMS Accession No. ML12145A529.

5 ADAMS Accession No. ML13002A339.

6 ADAMS Accession No. ML133048418.

7 ADAMS Accession No. ML133318490.

OFFICIAL USE ONLY SECURITY RELATED INFORMATION

OFFICIAL USE ONLY SECURITY RELATED INFORMATION

3.0 TECHNICAL EVALUATION

3.1 Seismic Licensing Basis Information The licensee provided information on the plant-specific licensing basis for the Seismic Category I SSCs for SSES-1 in Section 2.0, Seismic Licensing Basis, of its walkdown report. Consistent with the walkdown guidance, the NRC staff noted that the report includes a summary of the Safe Shutdown Earthquake and a description of the codes, standards, and methods that were used in the design of the Seismic Category I SSCs for meeting the c seismic licensing basis requirements.

Based on its review, the NRC staff concludes that the """'"""'" information on the plant-specific seismic licensing basis and a description of and mitigation features considered in the licensing bases evaluation consistent ittal Report, of the walkdown guidance.

3.2 Section 2, Personnel Qualifications; Section 3, Walkdowns and Area Walk-Bys; and Section 5, walkdown guidance (EPRI Document implementation of an appropriate seis ize the walkdown he walkdown report dated guidance. The NRC staff walkdown report meets the The NRC staff lkdown methodology implementation

• Development(){ the

• lmplementation.of the Process

• Licensing Basis Evaluations and Results 3.2.1 PersonneiQualification~

Section 2, Personnel Qualifications, of the walkdown guidance provides licensees with qualification information for personnel involved in the conduct of the seismic walkdowns and area walk-bys.

The NRC staff reviewed the information provided in Section 3.0, Personnel Qualifications, of the walkdown report, which includes information on the walkdown personnel and their qualifications.

Specifically, the NRC staff reviewed the summary of the background, experience, and level of involvement for the following personnel involved in the seismic walkdown activities: equipment 8 ADAMS Accession No. ML12200A069.

OFFICIAL USE ONLY SECURITY RELATED INFORMATION

OFFICIAL USE ONLY SECURITY RELATED INFORMATION selection personnel, seismic walkdown engineers (SWEs), licensing basis reviewers, IPEEE reviewers, peer review team, and operations staff.

Based on the review of the licensee's submittals, the NRC staff concludes that those involved in the seismic walkdown activities have the appropriate seismic background, knowledge and experience, as specified in Section 2 of the walkdown guidance.

3.2.2 Development of the SWELs Section 3, Selection of SSCs, of the walkdown guidance provides i to licensees for selecting the SSCs that should be placed on the SWELs, so be walked down by qualified personnel.

The NRC staff reviewed the overall process used by the the SSES-1 base list, SWEL 1 (sample list of designated safety functi 2 (sample list of spent fuel pool (SFP) related equipment). The I components common to both, SSES-1 and SS were included as part of the SWEL 2. The screening process shown in Figures 1-1 and 1-2 of the walkdown report, SSES-1 walkdown guidance. Specifically, the ng selection:

• A variety of systems, equip

• IPEEE equipme

• As stated above, the re included as part of the SWEL 2. The licensee explained, in of the walkdown report, that the piping, valves, ~nd equi ciated ormal SFP cooling functions are classified as Seismic Categorfttfor Therefore, no SPF equipment satisfied Screen #1 described in Figure 1-2 of the watkdown . Further, the NRC staff also noted that a rapid drain-down list was not includedas SWEL 2, as described in Section 3 of the guidance. In Section 4.3 of the walkdown report, icensee stated that SSES-1 does not have any SFP penetrations below 10 feet apove the top of the fuel assemblies. After reviewing the information provided in this section, the Nee staff concludes that the licensee provided sufficient information to justify that t~are no items to be included as part of the SWEL 2 for SSES-1.

Due to individual plant~gurations and the walkdown guidance screening process followed to select the final SWEL equipment, it is possible that some classes of equipment will not be represented on the SWEL. The walkdown guidance recognizes this is due to the equipment not being present in the plant (e.g., some plants generate direct current power using inverters and therefore do not have motor generators) or the equipment being screened out during the screening process (the screening process is described in Section 3 of the walkdown guidance).

Based on the information provided, the NRC staff noted that a detailed explanation was provided justifying cases where specific classes of equipment were not included as part of the SWEL, and concludes that these exclusions are acceptable.

OFFICIAL USE ONLY SECURITY RELATED INFORMATION

OfFICIAl USE ONlY SECURITY RElATED INfORMATION After reviewing SWELs 1 and 2, the NRC staff concludes that the sample of SSCs represents diversity of component types and assures inclusion of components from critical systems and functions, thereby meeting the intent of the walkdown guidance. In addition, the staff notes that the equipment selection personnel were appropriately supported by plant operations staff as described in the walkdown guidance.

3.2.3 Implementation of the Walkdown Process Section 4, Seismic Walkdowns and Area Walk-Bys, of the walkdown information to licensees regarding the conduct of the seismic wa each site.

The NRC staff reviewed Section 5.0, Seismic Walkdowns of the walkdown report, which summarizes the results of the seismic wa k-bys, including an overview of the number of items walked down and by. The walkdown report states that a team, which co UU'vLCU the seismic walkdowns and area walk-bys. Accordi (SWCs) and area walk-by checklists (AWCs),

October 26, 2012.

observations and judgments reed on the results of their of their review. Attachment report provides the of equipment on SWEL 1 checklists provided in As stated above, potentially adverse seismic conditions (PASCs) in the ent 8, Summary of Potentially Adverse Seismic Conditions an walkdown report list the PASCs identified during the seismic wal the area The table describes how each condition was adctre.ssed (e.g.,.,flkace the CAP), its resolution and current status. Based on the initial review of the che~ts, staff was unable to confirm that all the PASCs identified during the walkdowns w~r~in *stable. As such, by letter dated November 1, 2013, the NRC staff issued two qtii&tions request for additional information (RAI) in order to obtain additional clarification'ffgarding the process followed by the licensee when evaluating conditions identified in the fiEiWduring the walkdowns and walk-bys. Specifically, in RAI 1, the staff requested the licens~,~~>provide further explanation regarding how a field observation was determined to be PASC~,*ifto ensure that the basis for determination was addressed using normal plant processes and documented in the walkdown report. In response to RAI 1, the licensee detailed the step-by-step approach that was adapted by the SWE team during the seismic walkdown for equipment items considered not to be PASCs (no CAP entry needed) and for those found to be PASCs (entered into the CAP). The licensee confirmed that observations that could not be readily judged to be acceptable during the walkdown, were properly documented in the SWCs and AWCs. Observations determined to be PASCs were entered into the CAP by creating a condition report (CR). A Licensing Basis Evaluation (LBE) was performed for those observations that could not be evaluated by existing documentation, engineering judgment, or simple analysis. LBEs were performed within the CAP and documented therein. The licensee referred to Attachment 8 of the walkdown report which OFFICIAl USE ONlY SECURITY RElATED INFORMATION

OfFICIAl US~! ONlY SI!CURITY Rl!lATI!D INFORMATION includes a description of all these items. Furthermore, the licensee generated CR-2013-03407 to further confirm the adequacy of the process followed by the SWEs when dispositioning field observations. The licensee stated that this effort verified that the basis for any status change (Yes/No/Unknown) in the SWC and AWC for an equipment item between the field and final documentations was properly documented. The licensee also confirmed that no new conditions were identified that warranted a change in the PASCs listed in Attachment 8 of the walkdown report.

After reviewing the licensee's response and Attachment 8 of the 'A'""'"'"r report, the NRC staff concludes that the licensee responded appropriately to RAI 1, properly identified and documented, and the summary table in Attachment 8 is co complete.

In addition to the information provided above, the NRC rage configurations were verified to be consistent with existing plant docum 50 percent of the SWEL items, in accordance with Section 4 of the Section 5.3, Summary of Seismic Walkdowns, were opened to ensure that visibly accessible i Additional walkdowns will be conducted during inspections of selected cabinets that were not com the initial walkdowns.

The equipment and areas that were period are listed in , Inaccessible Equipment, list of inaccessible items also includes the condition caused A limited number of SWEL components (total of 25) sible I walkdowns. The licensee stated that nine of th but to be reinspected to verify the internal co The other SWEL components could not be walked-down of high radiation or safety risks were involved during pi were performed in the immediate area surrou ponents. The walkdowns for the inaccessible items were to be d by the end of the next scheduled refueling outage (spring 2014}. The I committed to provide a supplemental submittal with the results of these walkdown ite 60 days after the completion of the spring 2014 outage.

Based on the information pf'o;y~ded licensee's submittals, the NRC staff concludes that the licensee's implementation offhe walkdown process meets the intent of the walkdown guidance.

3.2.4 Licensing Basis Evakiations and Results Section 5, Seismic Ueensfng Basis Evaluations, of the walkdown guidance provides information to licensees regarding the conduct of licensing basis evaluations for items identified during the seismic walkdowns as degraded, nonconforming, or unanalyzed that might have potential seismic significance.

The NRC staff reviewed Section 6.0, Licensing Basis Evaluations, of the SSES-1 walkdown report, which discusses the process for conducting the seismic LBEs of the PASCs identified during the seismic walkdowns and area walk-bys. The licensee stated that it performed its LBEs for five of the identified PASCs. These LBEs were performed for all observations that could not be evaluated by existing documentation, engineering judgment, or simple analysis OffiCIAl US~! ONlY SI!CURITY Rl!lATI!O INfORMATION

OFFICIAl USE ONlY SECURITY RElATED INFORMATION within the CAP. Section 6.3, Licensing Basis Evaluation Summaries, of the walkdown report provides summaries of the performed LBEs. These summaries describe the actions taken or planned to address these conditions, including the current status of each of the items the licensee entered into the CAP.

The NRC staff reviewed the LBEs and CAP entries and the description of the actions taken or planned to address deficiencies. The staff concludes that the licensee appropriately identified potentially degraded, nonconforming, or unanalyzed conditions and entered them into the CAP, which meets the intent of the walkdown guidance.

3.2.5 Conclusion Based on the discussion above, the NRC staff concludes 's implementation of seismic walkdown methodology meets the intent of the for personnel qualifications, development of the SWELs, impleme u~.oc;;:,;:,, and seismic licensing basis evaluations.

3.3 Peer Review Section 6, Peer Review, of the walkdown guidance

• regarding the conduct of peer reviews e activities walkdowns. Page 6-1 of the wa1Ka1:Jwr conducted during the peer review

• Review a sample walkdowns and area walk-bys

• Review the li

• Review the

• Review the in the walkdown report The NRC staff revievi/ed,;the i n provided in Section 8.0, Peer Review, of the SSES-1 walkdown report which uct of the peer review. In addition, the NRC staff reviewed the response to~ 2. 2, the NRC staff requested the licensee to provide additional information on the~verall r review process that was followed as part of the walkdown activities. SpecifiGafty, the NRC staff requested the licensee to confirm that the activities identified in page ~ttOf the walkdown guidance were assessed and documented in the report. The Hcensee ~:also requested to confirm that any individual involved in performing any given ~own activity was not a peer reviewer for that same activity. In response to RAI 2, the licensee confirmed that all the activities identified on page 6-1 of the walkdown guidance were included as part of the peer review process and referred to the summary of the peer review activities provided in Section 8 and Attachments 11 through 13 of the walkdown report. In addition, the licensee provided additional clarification on the responsibilities of those involved in the peer review activities and stated that none of the peer reviewers were involved in the seismic walkdown inspection process in order to further demonstrate the independence of the peer review process.

OFFICIAl USE ONlY SECURITY RELATED INFORMATION

OFfiCIAl USE ONlY SECURITY RElATED INfORMATION The NRC staff reviewed the licensee's summary of each of these activities, which included the peer review team members' level of involvement, the peer review findings, and resolution of peer review comments. After reviewing the licensee's submittals, the NRC staff concludes that the licensee sufficiently documented the results of the peer review activities and how these reviews affected the work described in the walkdown report.

Based on the discussion above, the NRC staff concludes that the licensee's results of the peer review and subsequent actions taken in response to the peer review meets the intent of Section 6 of the walkdown guidance.

3.4 IPEEE Information Section 7, IPEEE Vulnerabilities, of the walkdown guid *nrrn<=>T*nn to licensees regarding the reporting of the evaluations conducted an .,..C::Innrl<::"" to SeismiC vulnerabilities identified during the IPEEE program. and Generic Letter 88-20, "Individual Plant Examination for 10 CFR 50.54(f)," dated November 23, 1988,9 1icensees examination to identify any plant-specific vuln The licensee provided background information reg EE program. The licensee stated that there were two classes of bilities d in the IPEEE report: (1) As-found installation did not conform to design  ; and ic margin earthquake outliers.

A summary of these identified vulne

• of the conditions and their subsequent resolutions, was provided in lities, of the walkdown report.

Based on the NRC wal report, the NRC staff concludes that the licensee's erabilities (including anomalies, outliers and other findings)

• II as actions taken to eliminate or reduce them, meets the 3.5 The li~nsee did not identify ned or newly installed protection and mitigation features in the walkdown report.

3.6 NRC Oversight 3.6.1 lndepe~dent Verificatf~n by Resident Inspectors

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On July 6, 2012, 10 th&'JiPC issued Temporary Instruction (TI) 2515/188, "Inspection of Near-Term Task Force Recommendation 2.3 Seismic Walkdowns." In accordance with the Tl, NRC inspectors independently verified that the licensee implemented the seismic walkdowns in accordance with the walkdown guidance for SSES-1. Additionally, the inspectors independently performed walkdowns of a sample of seismic protection features. The inspection report dated 9 ADAMS Accession No. ML031150465.

10 ADAMS Accession No. ML12156A052.

OffiCIAl USE ONlY SECURITY RElATED INFORMATION

OFFICIAL USI5 ONLY SI5CURITY RI5LATI5D INFORMATION February 13, 2013, 11 documents the results of this inspection and states that no findings were identified.

4.0 INACCESSIBLE ITEMS The equipment and areas that were inaccessible during the 180-day period are listed in of the walkdown report. The list of inaccessible items also includes the condition which caused the delay of the walkdown. As discussed above, a limited number of SWEL components (total of 25) were inaccessible at the time of the initial owns. The walkdowns for all of the remaining inaccessible items were committed to be by the end of the next scheduled refueling outage (spring 2014). The licensee to provide a supplemental submittal with the results of these walkdown ite 60 days of the next scheduled refueling outage.

5.0 CONCLUSION

The NRC staff concludes that the licensee's im meets the intent of the walkdown guidance. T implementation of the walkdown guidance a and procedures, the licensee verified the plant basis; addressed degraded, ""'"""'"1'"

adequacy of monitoring and mainten staff notes that no immediate safety supplemental letter will be provided with (spring 2014) addressing commitment. The NRC information was p 11 ADAMS Accession No. ML13044A599.

OFFICIAL USI5 ONLY SI5CURITY RI5LATI5D INFORMATION

OFFICIAl USE ONLY SECURITY RELATED INFORMATION DRAFT STAFF ASSESSMENT OF SEISMIC WALKDOWN REPORT NEAR-TERM TASK FORCE RECOMMENDATION 2.3 RELATED TO THE FUKUSHIMA DAI-ICHI NUCLEAR POWER PLANT ACCIDENT PPL SUSQUEHANNA. LLC SUSQUEHANNA STEAM ELECTRIC STATION UNIT 2 DOCKET NO. 50-388

1.0 INTRODUCTION

On March 12, 2012, 1 the U.S. Nuclear Regulatory ~ission (NRC) issu' equest for information per Title 10 of the Code of Federal R~1ions, Subpart 50. 54(f) .~4(f) letter) to all power reactor licensees and holders of cons~ion permits iftactive or defeifedjistatus. The re~~es! was part of the implementation of lessonslij' d ~~'llrthe a~cid~nt at the Fukushima Da1-1ch1 nuclear power plant. Enclosure 3, "Recomme a~12'.3: Se1sm1c," 2 to the 50.54(f) letter requested licensees to conduct ~mic walkdow entify and address degraded, nonconforming, or unanalyzed conditi~,-the corre ,, action program (CAP), verify the adequacy of monitoring and maintenan

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No+ ' es, and r~,the results to the NRC.

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a. Information ~r~~~~g'the plant-s hazard licensing bases and a description of the proteptionand mitigati;yl featur ,, , nsidered in the licensing basis evaluation.

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c. A list of plant-specific vulnerabilities ... identified by the IPEEE [Individual Plant Examination of Extemi~I.Events] and a description of the actions taken to eliminate or reduce them . ; '

d. Results of the wali'down including key findings and identified degraded,

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nonconforming, o,t:1i:fnanalyzed conditions ...

e. Any planned or newly installed protection and mitigation features.

f. Results and any subsequent actions taken in response to the peer review.

In accordance with the 50.54(f) letter, Enclosure 3, Required Response Item 2, licensees were required to submit a response within 180 days of the NRC's endorsement of the seismic walkdown process. By letter dated May 29, 2012, 3 the Nuclear Energy Institute (NEI) staff 1 Agencywide Documents Access and Management System (ADAMS) Accession No. ML12053A340.

2 ADAMS Accession No. ML12056A049.

3 ADAMS Package Accession No. ML121640872.

Enclosure 2 DRAFT OFFICIAl USE ONLY SECURITY RELATED INFORMATION

OffiCIAl USE ONlY SECURITY RElATED INFORMATION submitted Electric Power Research Institute (EPRI) document 1025286, "Seismic Walkdown Guidance for Resolution of Fukushima Near-Term Task Force Recommendation 2.3: Seismic,"

(walkdown guidance) to the NRC staff to consider for endorsement. By letter dated May 31, 2012, 4 the NRC staff endorsed the walkdown guidance.

By letter dated November 26, 2012, 5 PPL Susquehanna, LLC (PPL or the licensee) provided a response to Enclosure 3 of the 50.54(f) letter Required Response Item 2, for Susquehanna Steam Electric Station Unit 2 (SSES-2). In addition to the aforementi letter, the licensee, by letter dated July 26, 2013, 6 provided an updated submittal to seismic walkdown report. The purpose of the latter submittal was to update and inaccessible components not completed in the first submittal.

The NRC staff reviewed the walkdown report and n~1*~rrn1 supplemental information would assist the staff in completing its mber 1, 2013, 7 the NRC requested additional information to gain a uv*::;:,;:,.:;;:, and procedures used by the licensee in conducting responded to the NRC staff request by letter d The NRC staff evaluated the licensee's submittals the information provided in the walkdown report met the intent of the guid the licensee responded appropriately to Enclosure 3 of the 2.0 The structures, systems, in operating nuclear power plants are d , or meet intent of Appendix A to 10 CFR Part 50, Power Plants," Criterion 2: "Design bases for protection aga ndix A to 10 CFR Part 100, "Reactor Site Criteria." Criterion 2 at nuclear power plants shall be designed to withstand such as earthquakes, tornadoes, hurricanes, fl()o.;:*Pun of capability to perform their safety functions. * * *

• For initi.at licensing, each an see ired to develop and maintain design bases that, as defined by 10 CFR 50.2, ideri:tify the functions that an SSC of a facility must perform, and the specific values or ranges of values chosen for controlling parameters as reference bounds for the design.

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The design bases for tt}~SSCs reflect appropriate consideration of the most severe natural phenomena that have been historically reported for the site and surrounding area. The design bases also reflect sufficient margin to account for the limited accuracy, quantity, and period of time in which the historical data have been accumulated.

4 ADAMS Accession No. ML12145A529.

5 ADAMS Accession No. ML13002A339.

6 ADAMS Accession No. ML13211A348.

7 ADAMS Accession No. ML133048418.

8 ADAMS Accession No. ML133318490.

OffiCIAl USE ONlY SECURITY RElATED INFORMATION

OFFICIAl USE ONlY SECURITY RElATED INFORMATION The current licensing basis is the set of NRC requirements applicable to a specific plant, including the licensee's docketed commitments for ensuring compliance with, and operation within, applicable NRC requirements and the plant-specific design basis, including all modifications and additions to such commitments over the life of the facility operating license.

3.0 TECHNICAL EVALUATION

3.1 Seismic Licensing Basis Information The licensee provided information on the plant-specific licens* r the Seismic Category I SSCs for SSES-2 in Section 2.0, Seismic Licensing Basis, report. Consistent with the walkdown guidance, the NRC staff noted that the a summary of the Safe Shutdown Earthquake (SSE) and a description of and methods that were used in the design of the Seismic Category I licensing basis requirements.

Based on its review, the NRC staff concludes on the plant-specific seismic licensing basis and a de considered in the licensing bases evaluation consi walkdown guidance.

3.2 4, Seismic Basis Evaluations, of the des to licensees regarding the methodology. By letter dated July 10, walkdown guidance in the performance of The walkd~rep~,lil 26, supplemented by letter dated July 26, 2013, did not i4entify deqy "", walkdown guidance. The NRC staff reviewed the procedure and methodology and' the walkdown report meets the intent of the walkdown guidance.

The NRC staff reviewed th~~~owing sections of the walkdown methodology implementation provided in the walkdown reij)ft:

• Perso~l Qtliltfrcations

• Develop- ~f the Seismic Walkdown Equipment Lists (SWELs)

• Implementation of the Walkdown Process

• Licensing Basis Evaluations and Results 9 ADAMS Accession No. ML12200A069.

OffiCIAl USE ONlY SECURITY RElATED INfORMATION

OffiCIAl USE ONLY SECURITY RELATED INFORMATION 3.2.1 Personnel Qualifications Section 2, Personnel Qualifications, of the walkdown guidance provides licensees with qualification information for personnel involved in the conduct of the seismic walkdowns and area walk-bys.

The NRC staff reviewed the information provided in Section 3.0, Personnel Qualifications, of the walkdown report, which includes information on the walkdown pers and their qualifications.

Specifically, the NRC staff reviewed the summary of the backgrou rience, and level of involvement for the following personnel involved in the seismic activities: equipment selection personnel, seismic walkdown engineers (SWEs), li reviewers, IPEEE reviewers, peer review team, and operations staff.

Based on the review of the licensee's submittals, the the seismic walkdown activities have the appropri experience, as specified in Section 2 of the wal 3.2.2 Development of the SWELs Section 3, Selection of SSCs, of the information to licensees for selecting the SSCs that should be pi they can be walked down by qualified personnel.

The NRC staff reviewed the lop the SSES-2 base list, SWEL 1 (sample list , and SWEL 2 (sample list of spent fuel pool (SFP) no items were included as part of the SWEL 2. n process followed the screening process shown in Figures 1 . Based on Attachment 1 of the walkdown report, n requirements of the walkdown guidance.

Specifically, the followi the sample selection:

• ,A vade'ty

• • IPEEE equ*c.........-JnT

• Major new or

• Risk consid""""t'"-

The NRC staff ~ed that ms were included as part of the SWEL 2. The licensee explained, in Secti~ 4. L 2 Development, of the walkdown report, that the piping, valves, and equipment ass c *

• with the normal (SFP) cooling functions are classified as Seismic Category II for SSES. Therefore, there were no SPF equipment that satisfied Screen #1 described in Figure 1-2 of the walkdown guidance. The NRC staff also noted that a rapid drain-down list was not included as part of the SWEL 2, as described in Section 3 of the guidance. In Section 4.3 of the walkdown report, the licensee stated that SSES-2 does not have any SFP penetrations below 10 feet above the top of the fuel assemblies. After reviewing the information provided in this section, the NRC staff concludes that the licensee provided sufficient information to justify that there are no items to be included as part of the SWEL 2 list for SSES-2.

OFfiCIAl USE ONLY SECURITY RELATED INFORMATION

OFFICIAL USE ONLY SECURITY RELATED INFORMATION Due to individual plant configurations and the walkdown guidance screening process followed to select the final SWEL equipment, it is possible that some classes of equipment will not be represented on the SWEL. The walkdown guidance recognizes this is due to the equipment not being present in the plant (e.g., some plants generate direct current power using inverters and therefore do not have motor generators) or the equipment being screened out during the screening process (the screening process is described in Section 3 of the walkdown guidance).

Based on the information provided, the NRC staff noted that a detailed explanation was provided justifying cases where specific classes of equipment were n included as part of the SWEL, and concludes that these exclusions are acceptable.

After reviewing SWELs 1 and 2, the NRC staff concludes le of SSCs represents diversity of component types and assures inclusion of com critical systems and functions, thereby meeting the intent of the walkdown g * , the staff notes that the equipment selection personnel were appropriate ns staff as described in the walkdown guidance.

own guidance provides alkdowns and area walk-bys for The NRC staff reviewed Section 5.0, Se k-Bys, of the walkdown report, which summarizes th Its of walk-bys, including an overview of the number ked areas walked-by. The walkdown report ich of two qu ed SWEs, conducted the seismic walkdowns to the signed seismic walkdown checklists (SWCs) and area activities were conducted during July 10, to October 26, 2012. I kdowns were performed during April 25, to May 3, 2013, as purpose of the last activity was to complete a numf:Jer Qf during the initial walkdowns.

The walkdown report* the SWEs discussed their observations and judgments with each other during ditionally, the SWEs agreed on the results of their seismic wall<downs and ar

• a reporting the results of their review. Attachment 6, Seismic Walkdown and Are lk-By Checklists, of the walkdown report and Attachment 18, Seismic Walkdown and Area,". lk-By Checklists for Inaccessible Equipment Item Seismic Walkdowns, of the supple~tal report, provide the completed SWCs and AWCs, documenting the results for each *item*oh~quipment on SWEL 1 and each area containing SWEL equipment.

The licensee used the cpecklists provided in Appendix C of the walkdown guidance report without modification.

The licensee documented cases of potentially adverse seismic conditions (PASCs) in the checklists for further evaluation. Attachment 8, Summary of Potentially Adverse Seismic Conditions and Minor Issues/Concerns, of the initial walkdown report and Attachment 20, Summary of Potentially Adverse Seismic Conditions and Minor Issues/Concerns, of the supplemental report list the PASCs and issues/concerns identified during the seismic walkdowns and the area walk-bys. The table describes how each condition was addressed (e.g., placement in the CAP), its resolution and current status. Based on the initial review of the OFFICIAL USE ONLY SECURITY RELATED INfORMATION

OffiCIAl USE ONlY SECURITY REbATED INFORMATION checklists, the NRC staff was unable to confirm that all the PASCs identified during the walkdowns were included in this table. As such, by letter dated November 1, 2013, the NRC staff issued two questions in a request for additional information (RAI) in order to obtain additional clarification regarding the process followed by the licensee when evaluating conditions identified in the field during the walkdowns and walk-bys. Specifically, in RAI 1, the staff requested the licensee to provide further explanation regarding how a field observation was determined to be PASC, and to ensure that the basis for determination was addressed using normal plant processes and documented in the walkdown report. In to RAI 1, the licensee detailed the step-by-step approach that was adapted by team during the seismic walkdown for equipment items considered not to be CAP entry needed) and for those found to be PASCs (entered into the CAP). The I irmed that observations that could not be readily judged to be acceptable during re properly documented in the SWCs and AWCs. Observations were entered into the CAP by creating a condition report (CR). A E) was performed for those observations that could not be ntation, engineering judgment, or simple analysis. LBEs documented therein. The licensee referred to 0 of the supplemental report which Furthermore, the licensee generated CR-2013-034 process followed by the SWEs when ning this effort verified that the basis for for an equipment item between the The licensee also confirmed that no the PASCs listed in Attachm 8 of the After reviewing the li nt 8 of initial walkdown report and 0 of staff concludes that the licensee responded appropriately to and documented and the summary tables in Attachment of the supplemental report were considered complete.

In addition to the information ed above, the NRC staff notes that anchorage configurations were verified to be consistent v*co 1"n" plant documentation for at least 50 percent of the SWEL items, in accordanee,with 4 of the walkdown guidance.

Section 5.3, Summary of Sei~ic Walkdowns, of the walkdown report confirms that cabinets were opened to, ensure that v~bly accessible internal component mountings were adequate.

Additional walkdowns wer~,oonducted, as described in the supplemental report, to perform internal inspections,Qf s ed cabinets that were not completely inspected or were not opened during the initial walkd s.

Based on the information provided in the licensee's submittals, the NRC staff concludes that the licensee's implementation of the walkdown process meets the intent of the walkdown guidance.

3.2.4 Licensing Basis Evaluations and Results Section 5, Seismic Licensing Basis Evaluations, of the walkdown guidance provides information to licensees regarding the conduct of licensing basis evaluations for items identified during the OffiCIAl USE ONlY SECURITY RElATED INFORMATION

OFFICIAL USE ONLY SECURITY RELATED INFORMATION seismic walkdowns as degraded, nonconforming, or unanalyzed that might have potential seismic significance.

The NRC staff reviewed Section 6.0, Licensing Basis Evaluations, of the SSES-2 walkdown report, which discusses the process for conducting the seismic licensing basis evaluations of the PASCs identified during the seismic walkdowns and area walk-bys. The licensee stated that no licensing basis evaluations were required. Issues identified during the walkdowns and area walk-bys were dispositioned through the plant's CAP.

The NRC staff reviewed the CAP entries and the description of s taken or planned to address deficiencies. The staff concludes that the licensee ly identified potentially degraded, nonconforming, or unanalyzed conditions and the CAP, which meets the intent of the walkdown guidance.

3.2.5 Conclusion Based on the discussion above, the NRC staff n of seismic walkdown methodology meets the intent qualifications, development of SWELs, impleme licensing basis evaluations.

3.3 Peer Review Section 6, Peer Review, of with information regarding the conduct of during the seismic walkdowns. Page 6-1 lowing activities to be conducted during

• Review the

• Review a sample the seismic walkdowns and area walk-bys

• Re¥ieWthe licensing

• Revtew the deCi$ions

• Review the walkd~ repo

• summarize the resu'~:,f the r review process in the walkdown report The NRC staff reviewed the iiJormation provided in Section 8, Peer Review, of the SSES-2 walkdown report Which d~es the conduct of the peer review. In addition, the NRC staff reviewed the respcmse.to;RAI 2. In RAI 2, the NRC staff requested the licensee to provide additional information ()llthe overall peer review process that was followed as part of the walkdown activities. Specifically, the staff requested the licensee to confirm that the activities identified in page 6-1 of the walkdown guidance were assessed and documented in the report.

The licensee was also requested to confirm that any individual involved in performing any given walkdown activity was not a peer reviewer for that same activity. In response to RAI 2, the licensee confirmed that all the activities identified on page 6-1 of the walkdown guidance were included as part of the peer review process and referred to the summary of the peer review activities provided in Section 8 and Attachments 11 through 13 of the walkdown report. In addition, the licensee provided additional clarification on the responsibilities of those involved in OFFICIAL USE ONLY SECURITY RELATED INFORMATION

OfFICIAl USE ONlY SECURITY RElATED INFORMATION the peer review activities and stated that none of the peer reviewers were involved in the seismic walkdown inspection process in order to further demonstrate the independence of the peer review process.

The NRC staff reviewed the licensee's summary of each of these activities, which included the peer review team members' level of involvement, the peer review findings, and resolution of peer review comments. After reviewing the licensee's submittals, the NRC staff concludes that the licensee sufficiently documented the results of the peer review and how these reviews affected the work described in the walkdown report.

Based on the discussion above, the NRC staff concludes 's results of the peer review and subsequent actions taken in response to the the intent of Section 6 of the walkdown guidance.

3.4 IPEEE Information Section 7, IPEEE Vulnerabilities, of the walkd nsees regarding the reporting of the evaluations cond vulnerabilities identified during the IPEEE program.

Letter 88-20, "Individual Plant Examin for Severe 50.54(f)," dated November 23, 1988,"

examination to identify any pia The licensee provided h!:!r*~t-nlrn program. The licensee stated that there were IPEEE report: (1) As-found installation did not (2) ic margin earthquake outliers.

A summary of ng a description of the conditions and their subsequentreso PEEE Vulnerabilities, of the walkdown report.

Based on the NRC ~taff's Section walkdown report, the staff concludes that the licensee's identification [-SIJec:mc vulnerabilities (including anomalies, outliers and other findings) identified;,b¥ the program, as well as actions taken to eliminate or reduce them, meets the intent of $ection e walkdown guidance.

10 ADAMS Accession No. ML031150465.

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OFFICIAl USE ONlY SECURITY RElATED INFORMATION 3.5 Planned Upgrades The licensee did not identify any planned or newly installed protection and mitigation features in the walkdown report.

3.6 NRC Oversight 3.6.1 Independent Verification by Resident Inspectors On July 6, 2012, 11 the NRC issued Temporary Instruction (TI) "Inspection of Near-Term Task Force Recommendation 2.3 Seismic Walkdowns." with the Tl, NRC inspectors independently verified that the SSES-2 licensee the seismic walkdowns in accordance with the walkdown guidance. Additiona ndently performed walkdowns of a sample of seismic protecti report dated February 13, 2013, 12 documents the results of this findings were identified.

4.0 CONCLUSION

The NRC staff concludes that the lice eismic walkdown methodology meets the intent of the walkdown g that, through the implementation of the walkdown g ance with plant processes and procedures, the licensee verified current seismic licensing basis; addressed degraded, nconformi nditions; and verified the adequacy of monitoring features. Furthermore, the staff notes that no i NRC staff reviewed the information pr'""'"n"*r to Enclosure 3 of 11 ADAMS Accession No. ML12156A052.

12 ADAMS Accession No. ML13044A599.

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