LG-13-145, Response to Request for Additional Information Associated with Near-Term Task Force Recommendation 2.3, Seismic Walkdowns

Response to Request for Additional Information Associated with Near-Term Task Force Recommendation 2.3, Seismic Walkdowns

ML13331B501
Person / Time
Site:	Dresden, Peach Bottom, Oyster Creek, Byron, Braidwood, Limerick, Clinton, Quad Cities, LaSalle, Crane
Issue date:	11/27/2013
From:	Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LG-13-145, RA-13-109, RS-13-265, TMI-13-160
Download: ML13331B501 (13)

Text

1 RS-13-265 RA-13-109 TMI-13-160 LG-13-145 ti November 27,2013 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pike Rockville, MD 20852 Braidwood Station, Units 1 and 2 Facility Operating License Nos. NPF-72 and NPF-77 NRC Docket Nos. STN 50-456 and STN 50-457 Byron Station, Units 1 and 2 Facility Operating License Nos. NPF-37 and NPF-66 NRC Docket Nos. STN 50-454 and STN 50-455 Clinton Power Station, Unit 1 Facility Operating License No. NPF-62 NRC Docket No. 50-461 Dresden Nuclear Power Station, Units 2 and 3 Renewed Facility Operating License Nos. DPR-19 and DPR-25 NRC Docket Nos. 50-237 and 50-249 LaSalle County Station, Units 1 and 2 Facility Operating License Nos. NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374 Limerick Generating Station, Units 1 and 2 Facility Operating License Nos. NPF-39 and NPF-85 NRC Docket Nos. 50-352 and 50-353 Oyster Creek Nuclear Generating Station Renewed Facility Operating License No. DPR-16 NRC Docket No. 50-219 Peach Bottom Atomic Power Station, Units 2 and 3 Renewed Facility Operating License Nos. DPR-44 and DPR-56 NRC Docket Nos. 50-277 and 50-278 10 CFR 50.54(f)

U.S. Nuclear Regulatory Commission NTTF Recommendation 2.3: Seismic November 27, 2013 Page 2

References:

Quad Cities Nuclear Power Station, Units 1 and 2 Renewed Facility Operating License Nos. DPR-29 and DPR-30 NRC Docket Nos. 50-254 and 50-265 Three Mile Island Nuclear Station, Unit 1 Renewed Facility Operating License No. DPR-50 NRC Docket No. 50-289 Exelon Generation Company, LLC Response to Request for Additional Information Associated With Near-Term Task Force Recommendation 2.3, Seismic Walkdowns

1. NRC Letter, Request for Additional Information Associated With Near-Term Task Force Recommendation 2.3, Seismic Walkdowns, dated November 1, 2013

2. Exelon Generation Company, LLC's 180-day Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated November 27,2012, Braidwood Station, Units 1 and 2 (RS-12-159)

3. Exelon Generation Company, LLC's 180-day Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated November 27,2012, Byron Station, Units 1 and 2 (RS-12-161)

4. Exelon Generation Company, LLC's 180-day Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated November 27,2012, Clinton Power Station, Unit 1 (RS-12-165)

5. Exelon Generation Company, LLC's 180-day Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated November 27,2012, Dresden Nuclear Power Station, Units 2 and 3 (RS-12-167)

6. Exelon Generation Company, LLC's 180-day Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated November 27,2012, LaSalle County Station, Units 1 and 2 (RS-12-163)

u.s. Nuclear Regulatory Commission NTTF Recommendation 2.3: Seismic November 27,2013 Page 3

7. Exelon Generation Company, LLC's 180-day Response to NRC Request for Information Pursuant to 10 CFR SO.S4(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated November 19, 2012, Limerick Generating Station, Units 1 and 2 (RS-12-171)

8. Exelon Generation Company, LLC's 180-day Response to NRC Request for Information Pursuant to 10 CFR SO.S4(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated November 19, 2012, Oyster Creek Nuclear Generating Station (RS-12-177)

9. Exelon Generation Company, LLC's 180-day Response to NRC Request for Information Pursuant to 10 CFR SO.S4(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated November 19, 2012, Peach Bottom Atomic Power Station, Units 2 and 3 (RS-12-173)

10. Exelon Generation Company, LLC's 180-day Response to NRC Request for Information Pursuant to 10 CFR SO.S4(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated November 27,2012, Quad Cities Nuclear Power Station, Units 1 and 2 (RS-12-169)

11. Exelon Generation Company, LLC's 180-day Response to NRC Request for Information Pursuant to 10 CFR SO.S4(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated November 19, 2012, Three Mile Island Nuclear Station, Unit 1 (RS-12-17S)

12. Exelon Generation Company, LLC Supplemental Response to NRC Request for Information Pursuant to 10 CFR SO.S4(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated April 26, 2013, Oyster Creek (RS 06S)

13. Exelon Generation Company, LLC Supplemental Response to NRC Request for Information Pursuant to 10 CFR SO.S4(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima DaHchi Accident, dated April 30, 2013, Dresden Nuclear Power Station, Unit 3 (RS-13-067)

14. Exelon Generation Company, LLC Supplemental Response to NRC Request for Information Pursuant to 10 CFR SO.S4(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated June 19, 2013, LaSalle County Station, Unit 2 (RS-13-097)

U.S. Nuclear Regulatory Commission NTTF Recommendation 2.3: Seismic November 27, 2013 Page 4

15. Exelon Generation Company, LLC Supplemental Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated June 27, 2013, Quad Cities Nuclear Power Station, Unit 1 (RS-13-136)

16. Exelon Generation Company, LLC Supplemental Response to NRC Request for Information Pursuant to 10 CFR 50.54(f) Regarding Seismic Aspects of Recommendation 2.3 of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident, dated October 7, 2013, Limerick Generating Station, Unit 2 (RS-13-138)

On November 1, 2013, the Nuclear Regulatory Commission (NRC) issued a Request for Additional Information (Reference 1) requesting licensees to provide information regarding the conduct of the Recommendation 2.3, Seismic Walkdowns and the peer review process based on the NRC staff's review of the walkdown reports and site audits performed at a sampling of plants. In References 2 through 16, Exelon Generation Company, LLC (EGC) submitted the respective Station responses regarding the performance of seismic walkdowns to verify current plant configuration with current seismic licensing basis, and verify the adequacies of monitoring and maintenance procedures.

The EGC response to the NRC Request for Additional Information is provided in the Enclosure.

This letter contains no new regulatory commitments.

Should you have any questions concerning the content of this letter, please contact Ron Gaston at (630) 657-3359.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 27th day of November 2013.

Respectfully, MJ~4r Keith R. Jury Vice President, Licensing and Regulatory Affairs Exelon Generation Company, LLC

Enclosure:

Exelon Generation Company, LLC Response to NRC Request for Additional Information - Near-Term Task Force Recommendation 2.3, Seismic Walkdowns

U.S. Nuclear Regulatory Commission NTTF Recommendation 2.3: Seismic November 27,2013 Page 5 cc:

Director, Office of Nuclear Reactor Regulation Regional Administrator - NRC Region I Regional Administrator - NRC Region III NRC Senior Resident Inspector - Braidwood Station NRC Senior Resident Inspector - Byron Power Station NRC Senior Resident Inspector - Clinton Power Station NRC Senior Resident Inspector - Dresden Nuclear Power Station NRC Senior Resident Inspector - LaSalle County Station NRC Senior Resident Inspector - Limerick Generating Station NRC Senior Resident Inspector - Oyster Creek Nuclear Generating Station NRC Senior Resident Inspector - Peach Bottom Atomic Power Station NRC Senior Resident Inspector - Quad Cities Nuclear Power Station NRC Senior Resident Inspector - Three Mile Island Nuclear Station, Unit 1 NRC Project Manager, NRR - Braidwood Station NRC Project Manager, NRR - Byron Station NRC Project Manager, NRR - Clinton Power Station NRC Project Manager, NRR - Dresden Nuclear Power Station NRC Project Manager, NRR - LaSalle County Station NRC Project Manager, NRR - Limerick Generating Station NRC Project Manager, NRR - Oyster Creek Nuclear Generating Station NRC Project Manager, NRR - Peach Bottom Atomic Power Station NRC Project Manager, NRR - Quad Cities Nuclear Power Station NRC Project Manager, NRR - Three Mile Island Nuclear Station, Unit 1 Mr. Robert H. Beall, NRR/DPR/PRB, NRC Mr. Eric E. Bowman, NRR/DPR/PGCB, NRC or Ms. Eileen M. McKenna, NRO/DSRAlBPTS, NRC Ms. Lisa Regner, NRR/JLD/JPMB, NRC Illinois Emergency Management Agency - Division of Nuclear Safety Director, Bureau of Radiation Protection - Pennsylvania Department of Environmental Resources Manager, Bureau of Nuclear Engineering - New Jersey Department of Environmental Protection Chairman, Board of County Commissioners of Dauphin County, PA Chairman, Board of Supervisors of Londonderry Township, PA Mayor of Lacey Township, Forked River, NJ S. T. Gray, State of Maryland R. R. Janati, Chief, Division of Nuclear Safety, Pennsylvania Department of Environmental Protection, Bureau of Radiation Protection

Enclosure Exelon Generation Company, LLC Response to NRC Request for Additional Information -

Near-Term Task Force Recommendation 2.3, Seismic Walkdowns (7 pages)

U.S. Nuclear Regulatory Commission NTTF Recommendation 2.3: Seismic November 27, 2013 Page 1 of 7 ENCLOSURE Exelon Generation Company, LLC Response to NRC Request for Additional Information -

Near-Term Task Force Recommendation 2.3, Seismic Walkdowns NRC Question No.1 Conduct of the walkdowns, determination of potentially adverse seismic conditions (PASCs), dispositioning of issues, and reporting As a result of the audits and walkdown report reviews, the NRC staff noted that licensees' interpretations of the seismic walkdown guidance varied, which resulted in meaningful differences in the process used to disposition identified issues and in the documentation that was provided to the NRC staff. In particular, the application of engineering judgment in determining what constituted a potentially adverse seismic condition (PASC), the threshold for conducting licensing basis evaluations (LBEs), and determining what information was to be reported to the NRC staff varied.

The NRC staff intended that conditions initially marked No (N) or Unknown (U) in the field by the seismic walkdown engineers (SWEs) for which an analysis or calculation was performed would be considered as PASCs and that an analysis or calculation constituted an LBE. The walkdown guidance allows for analysis as part of engineering judgment; however, the intent was to allow for only simple analyses that could be readily performed in support of engineering judgment.

Further, the walkdown activities were intended to allow for transparency in the licensee's process to demonstrate that PASCs were appropriately identified, that they were addressed in an appropriate manner, and the basis documented such that the current condition of the plant was clearly consistent with the CLB with regard to seismic capability.

During the audits, the NRC staff identified examples of field observations that were deemed not to be PASCs. However, the basis for the determination was not clearly recorded. In some cases, the field checklists were amplified by noting that the basis was engineering judgment.

During site audit discussions, the staff was able to trace the basis for the engineering judgments and found that in many cases they were appropriate. It is expected that these situations would not be included in the walkdown report.

There were other situations that a PASC and LBE were not reported; however, the NRC staff found during the audit that a calculation, analysis (more than just simple), or evaluation was conducted but informally. An example is a confirmatory calculation performed to demonstrate that six anchor bolts out of eight was not a seismically adverse condition. Another example would be an analysis to demonstrate that an existing, slightly short weld was as seismically sound as the prescribed weld length in the plant design documentation. The staff expected these types of conditions and evaluations to be captured in the licensee's normal plant processes (e.g., condition report or corrective action program (CAP)), and also reported in the walkdown report, since they were potentially adverse seismic conditions that required more than applying judgment or simple analysis to address.

The NRC staff also found that the process that was used to deal with a field observation that

U.S. Nuclear Regulatory Commission NTTF Recommendation 2.3: Seismic November 27,2013 Page 2 of 7 was deemed to be a PASC was also not completely described or captured in the report. In many cases, the licensee reported that an LBE was not performed. However, during the audits, it was clear that an LBE (or an equivalent determination method) was performed and used in determining whether a PASC should be entered into the CAP. The staff expects that these conditions would be reported in the walkdown report.

On the whole, through the audits, the NRC staff found that it was able to conclude that the intent of the guidance was met when the licensee's overall process was completely explained, the information was updated to reflect the actual process, and results were updated. The self-assessments conducted by the licensees of the audited plants also identified the lapse in the description of the process used by the licensee to identify a PASC and disposition it.

Therefore, in order to clarify the process that was followed, please provide a description of the overall process used by the licensee (and its contractors) to evaluate observations identified in the field by the SWEs. The process should include how a field observation was determined to be a PASC or not and how the bases for determinations were recorded. Once a determination was made that an observation was a PASC, describe the process for creating a condition report (or other tracking mechanism), performing the LBE (or other determination method), and the resultant action, such as entering it into the CAP, or documenting the result and basis.

Also, in order to confirm that the reported information supports concluding that the plant meets the CLB, please follow one of the following three acceptable alternatives:

(a) Provide a supplement to the table or text from the original walkdown report, if needed, to include similar conditions as the above examples and situations and for conditions for which a calculation, analysis (if more than a simple analysis), or evaluation was used for a determination. The supplement should include a short description of each condition, how it was dispositioned and the basis for the disposition, as follows: 1) for each condition that was entered into the CAP, provide the CAP reference number, initiation date, and (if known) the planned completion date, or 2) for all other conditions, provide the result of the LBE (or other determination method), the basis for the result, and how (or where) the result was captured in the plant's documentation or existing plant process.

(b) Following the plant's standard procedures, confirm that a new CAP entry has been made to verify if appropriate actions were taken when reporting and dispositioning identified PASCs (including conditions for which a calculation, analysis (if more than a simple analysis), or evaluation was used for a determination). The eventual CAP closeout, including the process followed and actions taken, should be in sufficient detail to enable NRC resident inspectors to follow up.

(c)

If no new conditions are identified for addition to the supplement or the CAP entry mentioned above is deemed not necessary, provide a statement of confirmation that all potentially seismic adverse conditions (including conditions for which a calculation, analysis (if more than a simple analysis), or evaluation was used for a determination) identified during the walkdowns and walk-bys were addressed and included in the report to the NRC.

u.s. Nuclear Regulatory Commission NTTF Recommendation 2.3: Seismic November 27, 2013 Page 3 of 7

Response

Exelon Process

Description:

The EGC process description for evaluation of SWE field observations, PASC determination, PASC recording, PASC entry into CAP, LBE (or other determination method) used for dis positioning PASCs and determination and documentation of bases for PASC dispositions and resulting actions is described below.

Field observations made by the EGC fleet were performed in accordance with Electric Power Research Institute (EPRI) 1025286, "Seismic Walkdown Guidance," which states on page 4-1:

"The SWEs are expected to conduct the Seismic Walkdowns and Area Walk-Bys together.

During these evaluations, the SWEs are expected to actively discuss their observations and judgments with each other. Additionally, the SWEs are expected to come to agreement on the results of their Seismic Walkdowns and Area Walk-Bys before reporting the results of their work.

For purposes of later review by others, it may be useful to describe on the Seismic Walkdown or Area Walk-By checklists features that, after significant discussion between the SWEs, were found to be seismically adequate. Any issue that cannot be resolved by consensus of the SWEs should be further evaluated in accordance with Section 5: Seismic Licensing Basis Evaluations.

If a condition cannot be easily determined to be acceptable, then that condition should be documented on the Seismic Walkdown or Area Walk-By checklist and evaluated further, as described in Section 5: Seismic Licensing Basis Evaluations."

Exelon Actions Taken:

In accordance with the guidance above, the EGC fleet SWEs conducted the walkdowns together, actively discussed their observations and judgments with each other and established agreement with item dispositions including determination if an observation was a potentially adverse seismic condition (PASC). Minor items such as surface corrosion, overhead bulbs with no soft targets below, etc..., were dispositioned as not being PASCs. The bases for dispositioning these minor items were noted on the Seismic Walkdown Checklists (SWCs) and Area Walk-By Checklists (AWCs) with no further actions taken. For any condition that could not be easily dispositioned in the field or by an immediate follow-up action (i.e. checking a drawing or calculation) an Issue Report (IR) was generated and entered into the corrective action program (CAP). These IR numbers are typically referenced on the SWCs and AWCs. Potential adverse seismic conditions (PASCs) including design non-conformances and degraded conditions were entered into the CAP and associated IRs were identified. The affects of the observations were weighted in the scenario of the design basis earthquake and whether the safety-related function would be impacted. IRs generated were not limited to anchorage, seismic interaction or degradation concerns, but also included housekeeping and other non-seismic issues. Some issue reports (I Rs) were written for trending and to improve current seismic housekeeping processes. The EGC fleet walkdown process established a very conservative pOSition regarding CAP entries in accordance with the

U.S. Nuclear Regulatory Commission NTTF Recommendation 2.3: Seismic November 27,2013 Page 4 of 7 Exelon CAP policy of maintaining a low threshold for initiation of IRs. This is further described in the report excerpt below.

The Licensing Basis Evaluation Section of the EGC seismic walkdown reports typically state the following:

"The EPRI guidance document, Section 5: Seismic Licensing Basis Evaluations provides a detailed process to perform and document seismic licensing basis evaluations of SSCs identified when potentially adverse seismic conditions are identified. The process provides a means to identify, evaluate and document how the identified potentially adverse seismic condition meets a station's seismic licensing basis without entering the condition into a station's Corrective Action Program (CAP). In lieu of this process, Exelon utilized the existing processes and procedures (Site CAP Expectations) to identify, evaluate and document conditions identified during the Seismic Walkdowns.

In accordance with Exelon processes and procedures, all questionable conditions identified by the SWEs during the walkdowns were entered into the station CAP to be further evaluated and addressed as required. The SWEs provided input to support the identification and evaluation (including seismic licensing basis evaluations, as required) of the potentially adverse seismic conditions entered into the CAP. The station corrective action program is a more robust process than that provided in the EPRI guidance document; in part, ensuring each condition is properly evaluated for conformance with design and licensing bases and corrected as required.

Conditions identified during the walkdowns were documented on the SWCs, AWCs, and entered into the CAP. For those conditions that required, seismic licensing basis evaluations were completed and documented within the IR. Tables 5-2 and 5-3 in the report provide the IR, a summary of the condition, and the action completion status."

Exelon Actions Taken:

For the EGC fleet, the IRs generated from the walkdowns were dispositioned within the CAP and the bases for these dispositions are contained therein. Some IR dispositions resulted in no actions required, and in some cases work orders for field changes or document changes were initiated to restore proper equipment configuration and design margins. IR dispositions also document the bases for whether or not the condition was an adverse seismic condition. All identified conditions where any actual analysis or calculation was performed (Le., NRC defined LBEs) were documented in the CAP IR.

For any condition where degradation or non-conformance with design was identified, corrective actions were initiated for restoration of the item to its proper design configuration. In some rare cases, the non-conformance was evaluated, determined to be acceptable and design documents will be updated as required to show actual configuration. The resulting actions are traceable through the initiated IRs. These IRs were included in the November 2012 EGC fleet reports in Tables 5-2 and 5-3 and Tables A5-2 and A5-3 for follow-on supplemental walkdowns associated with inaccessible items and internal electrical cabinet inspections. Tables 5-2 and 5-3 identify the IRs generated during the Seismic Walkdowns and Area Walk-bys, respectively. The information in these tables includes the equipment identification, a description of the condition, the CAP item number (IR #) and resolution status (open/closed).

U.S. Nuclear Regulatory Commission NTTF Recommendation 2.3: Seismic November 27,2013 Page 5 of 7 EGC fleet IRs were normally generated the day they were discovered. For less significant conditions that did not involve operability concerns, a delay of several days may have occurred in some cases, typically to gather additional information (Le.

checking a drawing or calculation). Protocols were established for immediate communications with operations personnel where potential operability issues were discovered. The IRs generated included the necessary information for operations personnel to make the operability determination.

The follow-on supplemental walkdowns for inaccessible items and internal electrical cabinet inspections have applied the same walkdown methodologies as were used for the initial walkdowns on which the November 2012 EGC fleet reports are based.

Statement of Confirmation:

Based on the process used for the EGC fleet seismic walkdowns, and the reported information, it was determined that supplemental information was not necessary.

Therefore, "Response Alternative (c)" was chosen for confirmation that the EGC plants meet their Current Licensing Basis (CLB).

Based upon our review of the EGC seismic walkdown process used and the NRC submittal reports, no new conditions have been identified for the EGC plant sites that would require an additional supplement or additional CAP entries. These conditions were previously indentified in the initial NRC submittal reports for the EGC fleet (November 2012). These conditions where potential adverse seismic conditions (PASCs) (including conditions for which a calculation, analysis (if more than a simple analysis), or evaluation was used for a determination) were identified resulted in generation of an issue report (lR) and entry into the plant CAP. These IRs are listed in Tables 5-2 and 5-3 of the November 2012 NRC submittals. Updated IR lists following the supplemental walkdowns (in-progress through the end of 2014), associated with inaccessible items and internal electrical cabinet inspections, are included in Tables A5-2 and A5-3 of those submittals.

NRC Question No.2 Conduct of the Peer Review Process As a result of the walkdown report reviews, the NRC staff noted that some descriptions of the peer reviewers and the peer review process that was followed were varied and, in some cases, unclear. In some cases, the staff could not confirm details of the process, such as if the entire process was reviewed by the peer review team, who were the peer reviewers, what was the role of each peer reviewer, and how the reviews affected the work, if at all, described in the walkdown guidance.

Therefore, in order to clarify the peer review process that was actually used, please confirm whether the following information on the peer review process was provided in the original submittal, and if not, provide the following.

U.S. Nuclear Regulatory Commission NTTF Recommendation 2.3: Seismic November 27, 2013 Page 6 of 7 (a)

Confirmation that the activities described in the walkdown guidance on page 6-1 were assessed as part of the peer review process.

(b)

A complete summary of the peer review process and activities. Details should include confirmation that any individual involved in performing any given walkdown activity was not a peer reviewer for that same activity. If there were cases in which peer reviewers reviewed their own work, please justify how this is in accordance with the objectives of the peer review efforts.

Also, if there are differences from the original submittal, please provide a description of the above information. If there are differences in the review areas or the manner in which the peer reviews were conducted, describe the actual process that was used.

Response

Response to Question 2(a):

For the EGC plants sites, the activities described in the EPRI 1025286 walkdown guidance on page 6-1 were assessed as part of the peer review process and were provided in the original report submittals as indicated below. The results of the peer reviews were included in Attachment F of these submittals.

These activities are listed below:

Review the selection of the SSCs included on the SWEL 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 process Review the submittal report Summarize the results of the peer review process in the submittal report The Peer Review section of the EGC fleet reports typically state the following:

"A peer review team consisting of at least two individuals was assembled and peer reviews were performed in accordance with Section 6: Peer Reviews of the EPRI guidance document.

The Peer Review process included the following activities:

Review of the selection of SSCs included on the SWEL Review of a sample of the checklists prepared for the Seismic Walkdowns and Area Walk-Bys Review of Licensing basis evaluations, as applicable Review of the decisions for entering the potentially adverse conditions into the CAP process Review of the submittal report Provide a summary report of the peer review process in the submittal report

u.s. Nuclear Regulatory Commission NTTF Recommendation 2.3: Seismic November 27, 2013 Page 7 of 7 The peer reviews were performed independently from this report and the summary Peer Review Report is provided in Appendix F of this report."

Response to Question 2(b):

A complete summary of the peer review process and activities were provided in the original report submittals for the EGC fleet (Appendix F). EGC report peer review summaries typically included explicit confirmation that any individual involved in performing any given walkdown activity was not a peer reviewer for that same activity. (typical report statement provided below)

Some reports made statements having the same intent, though not stated as explicitly: "This report documents the independent peer review for the Near Term Task Force (NTTF)

Recommendation 2.3 Seismic Walkdowns performed". There were, however, no cases where any peer reviewer reviewed their own work for the EGC fleet.

Peer reviews performed for the follow-on supplemental walkdowns associated with inaccessible items and internal electrical cabinet inspections maintained similar scope and independence and therefore, the process has ensured that no cases exist where any peer reviewer reviewed their own work for the EGC fleet.