ML14120A162

Staff Assessment of the Seismic Walkdown Report Supporting Implementation of Near-Term Task Force Recommendation 2.3 Related to the Fukushima Dai-Ichi Nuclear Power Plant Accident

ML14120A162
Person / Time
Site:	Prairie Island
Issue date:	05/09/2014
From:	Scott Wall Plant Licensing Branch III
To:	Davidson K Northern States Power Co, Xcel Energy
Wall S
References
TAC MF0163
Download: ML14120A162 (13)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 May 9, 2014 Mr. Kevin K. Davison Site Vice President Northern States Power Company - Minnesota Prairie Island Nuclear Generating Plant 1717 Wakonade Drive East Welch, MN 55089

SUBJECT:

PRAIRIE ISLAND NUCLEAR GENERATING PLANT, UNIT 1 -STAFF ASSESSMENT OF THE SEISMIC WALKDOWN REPORT SUPPORTING IMPLEMENTATION OF NEAR-TERM TASK FORCE RECOMMENDATION 2.3 RELATED TO THE FUKUSHIMA DAI-ICHI NUCLEAR POWER PLANT ACCIDENT (TAC NO. MF0163)

Dear Mr. Davison:

On March 12, 2012, the U.S. Nuclear Regulatory Commission (NRC) issued a request for information letter per Title 10 of the Code of Federal Regulations, Subpart 50.54(f) (50.54(f) letter). The 50.54(f) letter was issued to power reactor licensees and holders of construction permits requesting addressees to provide further information to support the NRC staff's evaluation of regulatory actions to be taken in response to lessons learned from Japan's March 11, 2011 , Great Tohoku Earthquake and subsequent tsunami. The request addressed the methods and procedures for nuclear power plant licensees to conduct seismic and flooding hazard walkdowns to identify and address degraded, nonconforming, or unanalyzed conditions through the corrective action program , and to verify the adequacy of the monitoring and maintenance procedures.

By letter dated November 26, 2012, Northern States Power Company- Minnesota (NSPM) submitted its Seismic Walkdown Report as requested in Enclosure 3 of the 50.54(f) letter for the Prairie Island Nuclear Generating Plant, Unit 1. By letter dated November 27, 2013, NSPM provided a response to the NRC request for additional information for the staff to complete its assessments. By letter dated September 12, 2013, NSPM provided additional information on the completion of inaccessible items and the substitutions made to the list of inaccessible items, to support the completion of all of the walkdowns by the end of 2014.

The staff acknowledges that a supplemental letter will be provided within 60 days of the completion of refueling outage 1 R29 , currently scheduled for the fall of 2014, addressing the remaining inaccessible items, consistent with the regulatory commitment. The NRC staff reviewed the information provided and , as documented in the enclosed staff assessment, determined that sufficient information was provided to be responsive to Enclosure 3 of the 50.54(f) letter.

If you have any questions, please contact me at 301-415-2855 or by e-mail at Scott. Wall@ nrc.gov.

Sincerely, Scott Wall, Senior Project Manager Plant Licensing Branch 111-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-282

Enclosure:

Staff Assessment of Seismic Walkdown Report cc w/encl: Distribution via Listserv

STAFF ASSESSMENT OF SEISMIC WALKDOWN REPORT NEAR-TERM TASK FORCE RECOMMENDATION 2.3 RELATED TO THE FUKUSHIMA DAI-ICHI NUCLEAR POWER PLANT ACCIDENT NORTHERN STATES POWER COMPANY- MINNESOTA PRAIRIE ISLAND NUCLEAR GENERATING PLANT, UNIT 1 DOCKET NO. 50-282

1.0 INTRODUCTION

On March 12, 2012, 1 the U.S. Nuclear Regulatory Commission (NRC) issued a request for information per Title 10 of the Code of Federal Regulations, Subpart 50.54(f) (50.54(f) letter) to all power reactor licensees and holders of construction permits in active or deferred status. The request was part of the implementation of lessons learned from the accident at the Fukushima Dai-ichi nuclear power plant. Enclosure 3, "Recommendation 2.3: Seismic,"2 to the 50.54(f) letter requested licensees to conduct seismic walkdowns to identify and address degraded, nonconforming, or unanalyzed conditions using the corrective action program (CAP) , verify the adequacy of monitoring and maintenance procedures, and report the results to the NRC.

The 50.54(f) letter requested licensees to provide the following:

a. Information concerning the plant-specific hazard licensing bases and a description of the protection and mitigation features considered in the licensing basis evaluation.

b. Information related to the implementation of the walkdown process.

c. A list of plant-specific vulnerabilities identified by the Individual Plant Examination of External Events (I PEE E) program and a description of the actions taken to eliminate or reduce them .

d. Results of the walkdown including key findings and identified degraded, nonconforming, or unanalyzed 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

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 Northern States Power Company- Minnesota (the licensee) provided a response to Enclosure 3 of the 50.54(f) letter Required Response Item 2, for Prairie Island Nuclear Generating Plant (PINGP) Unit 1. The NRC staff reviewed the walkdown report and determined that additional supplemental information would assist the staff in completing its review. In letter dated November 1, 2013, 6 the NRC staff requested additional information to gain a better understanding of the processes and procedures used by the licensee in conducting the walkdowns and walk-bys. The licensee responded to the NRC staff request by letter dated November 27, 2013?

The NRC staff evaluated the licensee's submittals to determine if the information provided in the walkdown report met the intent of the walkdown guidance and if the licensee responded appropriately to Enclosure 3 of the 50.54(f) letter.

2.0 REGULATORY EVALUATION

The structures, systems, and components (SSCs) important to safety in operating nuclear power plants are designed either in accordance with , or meet the intent of Appendix A to 10 CFR Part 50, General Design Criteria (GDC) 2: "Design Bases for Protection Against Natural Phenomena;" and Appendix A to 10 CFR Part 100, "Reactor Site Criteria." GDC 2 states that SSCs important to safety at nuclear power plants shall be designed to withstand the effects of natural phenomena such as earthquakes, tornadoes, hurricanes, floods, tsunami, and seiches without loss of capability to perform their safety functions.

For initial licensing, each licensee was required to develop and maintain design bases that, as defined by 10 CFR 50.2, identify the specific 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.

The design bases for the 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.

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. ML12334A495 6

ADAMS Accession No. ML133048418 7

ADAMS Accession No. ML133338457

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 PINGP1 in Section 2.0 of the walkdown report. Consistent with the walkdown guidance, the staff noted that the report includes a summary of the Design Basis Earthquake (DBE), which the licensee stated is synonymous with the Safe Shutdown Earthquake, and the Operating Basis Earthquake as well as a description of the codes, standards, and methods that were used in the design of the Seismic Category I SSCs for meeting the plant-specific seismic licensing basis requirements. The NRC staff reviewed Section 2.0 of the walkdown report, focusing on the summary of the DBE and the design codes used in the design.

Based on the NRC staff's review, the staff concludes that the licensee has provided information on the plant-specific seismic licensing basis and a description of the protection and mitigation features considered in the licensing bases evaluation consistent with Section 8, Submittal Report, of the walkdown guidance.

3.2 Seismic Walkdown Methodology Implementation Section 2, Personnel Qualifications; Section 3, Selection of SSCs; Section 4, Seismic Walkdowns and Area Walk-Bys; and Section 5, Seismic Licensing Basis Evaluations, of the walkdown guidance provide information to licensees regarding the implementation of an appropriate seismic walkdown methodology. By letter dated July 9, 2012, 8 the licensee confirmed that it would utilize the walkdown guidance in the performance of the seismic walkdowns at PINGP1.

The walkdown report dated November 26, 2012, did not identify deviations from the walkdown guidance.

The NRC staff reviewed the following sections of the walkdown methodology implementation provided in the walkdown report:

• Personnel Qualifications

• Development of the Seismic Walkdown Equipment Lists (SWELs)

• Implementation of the Walkdown Process

• Licensing Basis Evaluations and Results 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 3.3, and Table 3-1 of the walkdown report, which includes information on the walkdown personnel and their qualifications.

Specifically, the staff reviewed the summary of the background, experience, and level of 8

ADAMS Accession No. ML12192A207

involvement for the following personnel involved in the seismic walkdown activities: equipment selection personnel, seismic walkdown engineers (SWEs), licensing basis reviewers, IPEEE reviewers, peer review team, and operations staff.

The NRC staff noted that the role and participation of the Operations staff is included in the Peer Review Introduction in Appendix E of the walkdown report.

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 information to licensees for selecting the SSCs that should be placed on the SWELs, so that they can be walked down by qualified personnel.

The NRC staff reviewed the overall process used by the licensee to develop the PINGP1 base list, SWEL 1 (sample list of designated safety functions equipment), and SWEL 2 (sample list of spent fuel pool related equipment) as described in Section 4.2 of the walkdown report. The overall equipment selection process followed the screening process shown in Figures 1-1 and 1-2 of the walkdown guidance. The staff noted that the licensee switched the order for Screens #3 and #4 from the walkdown guidance. Based on Section 4 and Appendix A of the walkdown report, PINGP1 SWELs 1 and 2 meet the inclusion requirements of the walkdown guidance.

Specifically, the following attributes were considered in the sample selection:

• A variety of systems, equipment and environments

• IPEEE equipment

• Major new or replacement equipment

• Risk considerations 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 DC 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.

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 4.2 of the walkdown report, the licensee stated that it did not identify any rapid drain-down flowpaths and therefore did not provide a rapid drain-down list. After reviewing the information provided in this section, the NRC staff concludes that the licensee provided sufficient information to justify not including rapid drain-down items as part of the SWEL 2.

By letter dated September 12, 2013, 9 the licensee stated that it made two component substitutions, to support the completion of the walkdowns of inaccessible items by the end of 2014. The licensee stated that the substituted items represent equipment of a comparable condition, design and environment. The NRC staff reviewed the licensee's proposed plans and the justification provided for the equipment substitution and agrees that the substituted items are comparable to the previous ones and located in similar environmental conditions. In addition, the staff concludes that the substitutions maintained the diversity of the equipment classes represented in the original SWEL. The licensee also proposed partial inspection of five cabinets that will still be energized during the proposed walkdowns and for which no suitable substitutions were identified. The NRC staff also reviewed the plans for partial inspections of the energized cabinets during which the licensee will be able to view anchorages but will be unable to fully open and inspect the cabinet internals. The staff noted that the licensee's initial walkdowns of eleven similar cabinets did not identify any adverse seismic conditions and the licensee stated that similar findings are expected for the inaccessible items. The NRC staff concludes that partial inspections of the cabinets, in addition to the internal cabinet inspections already completed are sufficient to meet the intent of the walkdown guidance and complete the walkdown activities by the end of 2014.

After reviewing SWELs 1 and 2, the NRC staff concludes that the sample of SSCs represent a 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 NRC 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 guidance provides information to licensees regarding the conduct of the seismic walkdowns and area walk-bys for each site.

The NRC staff reviewed Section 5 of the walkdown report, which summarizes the results of the seismic walkdowns and area walk-bys, including an overview of the number of items walked down and the number of areas walked-by. The walkdown report states that two teams consisting of at least two qualified SWEs conducted the seismic walkdowns and area walk-bys. The SWEs documented the results of the walkdowns on the seismic walkdown checklists (SWCs) and area walk-by checklists (AWCs). The walkdown report also states that the SWEs discussed their observations and judgments with each other during the walkdowns. Additionally, the SWEs agreed on the results of their seismic walkdowns and area walk-bys before reporting the results of their review. Appendices B and C of the walkdown report provide the completed SWCs and AWCs, documenting the results for each item of equipment on SWEL 1 and 2 and each area containing SWEL equipment. The licensee used the checklists 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. Tables 5-2 and 5-3 of the walkdown report list the PASCs identified during the seismic walkdowns and the area walk-bys, respectively. The tables 9

ADAMS Accession No. ML13259A028

describe how each condition was addressed (e.g., placement in the CAP), its resolution, and current status. Appendix F Tables F-1 and F-2 provide the status of additional observations made during the seismic walkdowns and area walk-bys, respectively.

Based on the review of the checklists, the NRC staff was unable to confirm that all the PASCs identified during the walkdowns were included in these tables. By letter dated November 1, 2013, the 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 NRC 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 response to RAI 1, the licensee confirmed that observations that could not be readily judged to be acceptable with respect to its current licensing basis during the walkdown , and were not previously evaluated as acceptable conditions through follow-up review of plant documentation, were placed in the PINGP1 CAP to determine if they were PASCs. The licensee noted that none of the concerns identified during the walkdowns were judged to be PASCs and referred to Tables 5-2 and 5-3 of the walkdown report, which includes all the observations identified during the walkdowns and area walk-bys for PINGP1 and were entered into the work management system for resolution.

Also, in response to RAI 1, the licensee clarified , that while Tables F-1 and F-2 list all observations identified during the walkdowns and walk-bys and how they were dispositioned, Tables 5-2 and 5-3 only include those observations that required additional review by site engineering. The licensee also conducted a full review of the SWCs and AWCs but did not identify any new conditions that would require entry into the CAP or additions to Tables 5-2, 5-3, F-1, or F-2. The licensee concluded that all conditions identified during the walkdowns and walk-bys were addressed and included in the walkdown report submitted to the NRC in November 2012. The licensee confirmed that no new conditions were identified.

After evaluating the licensee's response and reviewing Tables 5-2 , 5-3, F-1 , and F-2, the NRC staff concludes that the licensee responded appropriately to RAI 1, PASCs were properly identified and documented, and summary Tables 5-2 , 5-3, F-1 and F-2 are considered complete.

In addition to the information provided above, the NRC staff notes that anchorage configurations were verified to be consistent with existing plant documentation for at least 50 percent of the SWEL items, in accordance with Section 4 of the walkdown guidance.

The walkdown report confirms that cabinets were opened to view internal anchorages as part of the walkdowns, however, some cabinets could not be opened due to the energized nature of the equipment and were deemed inaccessible. Table D-1 of the walkdown report includes the items that were inaccessible during the initial walkdowns. The licensee stated that the internally mounted items on 18 electrical cabinets were inaccessible due to the energized nature of the cabinets. However, the external anchorage conditions and the immediate area surrounding these components were included during the initial walkdowns. The NRC staff noted that the cabinets will be opened during the licensee's next refueling outage. Since the licensee comm itted to open a representative number of cabinets to verify their internal components and provided the schedules for performing these actions, the staff concludes this is an acceptable approach.

The equipment and areas that were inaccessible during the 180-day period are listed in Table D-1 of the walkdown report. The list of inaccessible items also identifies the condition that caused the delay of the walkdown. A limited number of SWEL components (total of 29, including the 18 cabinets) were inaccessible at the time of the initial walkdowns. The remaining SWEL components which are located in areas where personnel safety concerns exist while the unit is in operation (e.g. inside containment), were inaccessible at the time of the initial walkdowns and will also be completed . The walkdowns for all of the remaining inaccessible items were committed to be completed by the end of the next scheduled refueling outage (fall2014). The licensee committed to provide a supplemental walkdown report with the results of these walkdown items within 60 days of the completion of the outage. The schedule for completion is consistent with the timing of the next scheduled refueling outage.

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 seismic walkdowns as degraded, nonconforming, or unanalyzed, which might have potential seismic significance.

The NRC staff reviewed Section 6 of the PINGP1 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 it performed its licensing basis evaluations and resolved PASCs using the CAP. Tables 5-2 and 5-3 of the walkdown report list the key licensee findings and provide a complete list of the potentially degraded, nonconforming, or unanalyzed conditions. These tables also 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 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 that the licensee's implementation of seismic walkdown methodology meets the intent of the walkdown guidance for personnel qualifications, development of SWELs, implementation of the walkdown process, and seismic licensing basis evaluations.

3.3 Peer Review Section 6, Peer Review, of the walkdown guidance provides licensees with information regarding the conduct of peer reviews for the activities performed during the seismic walkdowns. Page 6-1

of the walkdown guidance identifies the following activities to be conducted during the peer review process:

• Review the selection of the SSCs included on the SWELs

• Review a sample of the checklists prepared for the seismic walkdowns and area walk-bys

• Review the licensing basis evaluations

• Review the decisions for entering the potentially adverse conditions into the CAP

• Review the walkdown report

• Summarize the results of the peer review process in the walkdown report The NRC staff reviewed the information provided in Section 8 of the PINGP1 Walkdown Report, which describes the conduct of the peer review. In addition, the staff reviewed the response to RAI 2. In RAI 2, the staff requested the licensee to provide additional information on the overall peer review process that was followed as part of the walkdown activities. Specifically, the NRC 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 Appendix E of the walkdown report. In addition, the licensee stated that the peer reviewers were independent from the tasks being reviewed.

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 guidance provides information to licensees regarding the reporting of the evaluations conducted and actions taken in response to seismic vulnerabilities identified during the IPEEE program. Through the IPEEE program and Generic Letter 88-20, "Individual Plant Examination of External Events for Severe Accident Vulnerabilities," licensees previously had performed a systematic examination to identify any plant-specific vulnerabilities to severe accidents.

The licensee reported the actions taken to reduce or eliminate the seismic vulnerabilities identified during the IPEEE in Section 7 and Table 7-1 of the walkdown report. The licensee stated that the list of seismic vulnerabilities identified during the IPEEE program is available for inspection. Although the licensee did not clarify if the configuration management program has

maintained the IPEEE actions, the NRC staff noted that the IPEEE item included in the SWEL was not identified as a seismic concern and there are no discrepancies between the plant configuration and design documents.

Based on the NRC staff's review of Section 7 of the walkdown report, the staff concludes that the licensee's identification of plant-specific vulnerabilities (including anomalies, outliers, and other findings) identified by the IPEEE program, as well as actions taken to eliminate or reduce them, meets the intent of Section 7 of the walkdown guidance.

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, 10 the NRC 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 PINGP1 licensee implemented the seismic walkdowns in accordance with the walkdown guidance. Additionally, the inspectors independently performed walkdowns of a sample of seismic protection features. The inspection report dated February 7, 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 Appendix D Table D-1 of the walkdown report. The list of inaccessible items also identifies the condition that caused the delay of the walkdown. As discussed above, the deferred walkdowns for all of the remaining inaccessible SWEL items (total of 29) were committed to be completed by the end of the next scheduled refueling outage (fall2014). The licensee committed to provide a supplemental submittal with the results of these walkdown items within 60 days of the completion of the refueling outage.

The NRC staff concludes that the inaccessible equipment list was developed consistent with the walkdown guidance. The schedule for completion is consistent with the timing of the next scheduled outage.

5.0 CONCLUSION

The NRC staff concludes that the licensee's implementation of seismic walkdown methodology meets the intent of the walkdown guidance. The staff concludes that the licensee, through the 10 ADAMS Accession No. ML12156A052 11 ADAMS Accession No. ML13038A671

implementation of the walkdown guidance activities and, in accordance with plant processes and procedures, verified the plant configuration with the current seismic licensing basis; addressed degraded, nonconforming, or unanalyzed seismic conditions; and verified the adequacy of monitoring and maintenance programs for protective features. Furthermore, the NRC staff notes that no immediate safety concerns were identified. The staff acknowledges that the licensee will submit a supplemental letter within 60 days of the completion of the fall 2014 refueling outage that will address the remaining inaccessible items, consistent with the regulatory commitment. The NRC staff reviewed the information provided and determined that sufficient information was provided to be responsive to Enclosure 3 of the 50.54(f) letter.

If you have any questions, please contact me at 301-415-2855 or by e-ma il at Scott. Wall@nrc.gov.

Sincerely, IRA/

Scott Wall , Senior Project Manager Plant Licensing Branch 111-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-282

Enclosure:

Staff Assessment of Seismic Walkdown Report cc w/encl : Distribution via Listserv DISTRIBUTION :

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