ML12024A231

Requests for Additional Information for the Review of the Limerick Generating Station, Units 1 and 2, License Renewal Application (TAC Nos. ME6555 and ME6556) OE and Other RAIs

ML12024A231
Person / Time
Site:	Limerick
Issue date:	02/16/2012
From:	Robert Kuntz License Renewal Projects Branch 1
To:	Gallagher M Exelon Generation Co
Kuntz R
References
TAC ME6555, TAC ME6556
Download: ML12024A231 (8)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 February 16, 2012 Mr. Michael P. Gallagher Vice President License Renewal Projects Exelon Generation Company, LLC 200 Exelon Way Kennett Square, PA 19348

SUBJECT:

REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE LIMERICK GENERATING STATION, UNITS 1 AND 2, LICENSE RENEWAL APPLICATION (TAC NOS. ME6555 AND ME6556)

Dear Mr. Gallagher:

By letter dated June 22, 2011, Exelon Generation Company, LLC submitted an application pursuant to Title 10 of the Code of Federal Regulations Part 54 (10 CFR Part 54), to renew the operating licenses for Limerick Generating Station, Units 1 and 2, for review by the U.S. Nuclear Regulatory Commission (NRC or the staff). The staff is reviewing the information contained in the license renewal application and has identified, in the enclosure, areas where additional information is needed to complete the review.

These requests for additional information were discussed with Christopher Wilson, and a mutually agreeable date for the response is within 30 days from the date of this letter. If you have any questions, please contact me at 301-415-3733 or bye-mail at Robert.Kuntz@nrc.gov.

Sincerely,

~ Robert F. Kuntz, Senior Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-352 and 50-353

Enclosure:

Requests for Additional Information cc w/encl: Listserv

LIMERICK GENERATING STATION LICENSE RENEWAL APPLICATION REQUESTS FOR ADDITIONAL INFORMATION RAI8.1.4-1

Background

License Renewal Application (LRA) Section B.1.4 states that, during the first 10 years of entering the period of extended operation, the owners of programs credited for license renewal will perform a review of plant-specific and industry operating experience to confirm the effectiveness of the Aging Management Program (AMPs). This review wi" determine if the AMP is currently effective, requires modification, or identify a need to develop a new AMP. In addition, the LRA states that follow-up actions will be taken as appropriate to provide additional assurance that aging of systems, structures, and components in the scope of license renewal will be adequately managed throughout the period of extended operation.

LRA Section B.1.4 describes a plan to review operating experience once for each AMP after entering the period of extended operation. New operating experience information is generated daily; therefore, the proposed one-time review would not result in the timely consideration of operating experience. Further, if the operating experience review occurs only once in the first 10 years of entering the period of extended operation, then there will be a gap between that review and the renewed license expiration date, during which no operating experience will be considered to determine whether the AMPs are effective, require modification, or whether there is a need to develop new AMPs.

Request Describe programmatic activities that will be used for the ongoing review of plant-specific and industry operating experience to ensure that (a) the license renewal AMPs are and wi" continue to be effective in managing the aging effects for which they are credited, and (b) the AMPs wi" be enhanced or new AMPs will be developed when the review of operating experience indicates that the AMPs may not be fully effective.

In this description, address the following:

(a) If crediting existing activities, justify why they would not preclude the consideration of operating experience related to aging.

(b) Describe the sources of plant-specific and industry operating experience that will be reviewed for potential impacts on the aging management activities.

(c) Indicate whether plant-specific and industry operating experience only will be considered from a prescribed list of sources.

- 2 (d) Describe how plant-specific and industry operating experience evaluations will be prioritized and completed in a timely manner.

(e) Describe the operating experience evaluation records with respect to what will be considered and recorded on aging. Indicate whether the evaluation records will be maintained in auditable and retrievable form.

(f) When it is determined through an operating experience evaluation that enhancements to the aging management activities are necessary, including the development of new AMPs, describe how the enhancements will be implemented.

(g) Describe how the ongoing operating experience review activities will be administratively controlled. Indicate whether these administrative controls include periodic audits to ensure the effectiveness of the operating experience review activities.

(h) Describe how operating experience issues will be identified and categorized as related to aging. If an identification code is used, provide its definition or the criteria for its application. Also, describe how age-related operating experience will be trended.

(i) Indicate whether guidance documents and other publications are considered as a source of operating experience information. If they are considered as a potential source, provide a plan for considering the content of guidance documents, such as the GALL Report, as operating experience applicable to aging management. If they are not a potential source, justify why they should not be considered as such.

m Describe how evaluations of operating experience issues related to aging will consider the following:

• systems, structures, or components

• materials

• environments

• aging effects

• aging mechanisms

• AMPs (k) Describe criteria for considering when AMPs should be modified or new AMPs developed due to operating experience.

(I) Describe how the results of the AMP inspections, tests, analyses, etc. will be considered as operating experience, both when they meet and do not meet the applicable acceptance criteria.

(m) Describe the training requirements and justify the level of training on aging issues for those plant personnel responsible for screening, assigning, evaluating, and submitting

- 3 plant-specific and industry operating experience. Also, provide the periodicity of the training and describe how it will account for personnel turnover.

(n) Provide criteria for reporting plant-specific operating experience on age-related degradation to the industry.

RAI A.1-1

Background

Section 54.21(d} of 10 CFR requires the application to contain a final safety analysis report supplement. This supplement must contain a summary description of the programs and activities for managing the effects of aging and the evaluation of time-limited aging analyses for the period of extended operation.

LRA Appendix A contains the applicant's updated final safety analysis report (UFSAR) supplement. This supplement contains Commitment No. 46, which is to, "Perform a review of plant-specific and industry operating experience to confirm the effectiveness of the aging management programs." The implementation schedule for this commitment is "[d]uring the first 10 years of entering the period of extended operation."

As discussed above in RAI B.1.4-1, the implementation schedule would not provide for the timely consideration of operating experience. Further, this commitment does not adequately describe how operating experience will be considered to determine whether the AMPs are effective, require modification, or whether there is a need to develop new AMPs.

Reguest Consistent with the response to RAI 8.1.4-1 above, provide a summary description of the ongoing operating experience review activities for the final safety analysis report (FSAR) supplement required in accordance with 10 CFR 54.21 (d). If enhancements are necessary, identify them in the FSAR supplement and include the schedules for their implementation.

RAI3.4.1.11-1

Background

LRA item 3.4.1-11 addresses cracking due to stress corrosion cracking (SCC) of stainless steel piping, piping components, and piping elements, tanks, heat exchanger components exposed to steam or treated water greater than 60°C (140°F). LRA item 3.4.1-11 indicates that cracking due to SCC of the components is managed by the Water Chemistry and One-Time Inspection programs.

LRA Table 3.1.2-1 addresses the aging management review results for the reactor coolant pressure boundary. More specifically, LRA Table 3.1.2-1 addresses the stainless steel piping, piping components, and piping elements exposed to steam (internal), indicating that these

-4 components are related to LRA item 3.4.1-11 and cracking due to SCC of these stainless steel components are managed by the Water Chemistry and One-Time Inspection programs.

In comparison, GALL Report item IV.C1.R-20 and SRP-LR Table 3.1-1, ID 97 recommend GALL Report AMP XI.M7, "BWR Stress Corrosion Cracking," and GALL Report AMP XI.M2, "Water Chemistry," to manage cracking due to SCC and intergranular stress corrosion cracking (IGSCC) of stainless steel piping, piping components, and piping elements greater than or equal to four nominal pipe size (!\IPS) exposed to reactor coolant. GALL Report,Section IX.D, "Selected Definitions & Use of Terms for Describing and Standardizing Environments," states that reactor coolant is treated water in the reactor coolant system and connected systems at or near full operating temperature, including steam associated with BWRs.

The LRA credits the One-Time Inspection program to manage cracking due to SCC of the reactor coolant pressure boundary stainless steel piping, piping components, and piping elements exposed to steam (internal), which are addressed in LRA Table 3.1.2-1. The staff needs clarification as to whether any of these stainless steel components is included in the scope of the BWR Stress Corrosion Cracking program or the ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program, which includes periodic inspections. The staff also needs clarification as to the adequacy of the One-Time Inspection program.

Request

1. Provide information to clarify why any of these stainless steel components exposed to steam is not included in the scope of the BWR SCC program or the ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD program, which includes periodiC inspections (for example, describe the nominal pipe sizes, more specific component types, locations, and applicable inspection requirements of ASME Code,Section XI).

2. Justify why the One-Time Inspection program, which does not include periodic inspections, is adequate to manage cracking due to SCC of these stainless steel components.

As part of the response, clarify whether SCC has been observed in these components to demonstrate that the LGS operating experience supports the adequacy of the One-Time Inspection program to manage the aging effect.

3. Revise the LRA, consistent with the response to items 1 and 2 above.

RAI 3.5.2.11-1

Background:

LRA Table 3.5.1, item 3.5.1-78 states that the spent fuel pool liner is managed for loss of material and cracking by the Water Chemistry program and monitoring of the leak chase channel drainage system.

-5 LRA Tables 3.5.2-11 and 3.5.2-13 include several stainless steel components that reference item 3.5.1-78, but do not line the spent fuel pool. These include, but are not necessarily limited to, the debris screens in the primary containment system in LRA Table 3.5.2-11 and the integral attachments in the reactor enclosure system in LRA Table 3.5.2-13.

For stainless steel components other than the spent fuel pool liner that are exposed to treated water, the GALL Report typically recommends the One-Time Inspection program to verify the effectiveness of the Water Chemistry program (e.g., GALL Report item VII.A4.AP-110).

Issue:

Monitoring of the leak chase channel drainage may not be an appropriate activity to verify the effectiveness of the Water Chemistry program for all of the components in LRA Tables 3.5.2-11 and 3.5.2-13 that reference item 3.5.1-78.

Request:

Identify those items in LRA Tables 3.5.2-11 and 3.5.2-13 that reference LRA item 3.5.1-78 for which monitoring of the leak chase channel drainage system would not be expected to detect degradation. For those items, propose an alternative activity to verify the effectiveness of the Water Chemistry program.

SUB~IECT: REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE LIMERICK GENERATING STATION, LICENSE RENEWAL APPLICATION DISTRIBUTION:

HARDCOPY:

DLR RF E-MAIL:

PUBLIC [or NON-PUBLIC, if applicable]

RidsNrrDlr Resource

Mr. Michael P. Gallagher Vice President License Renewal Projects Exelon Generation Company, LLC 200 Exelon Way Kennett Square, PA 19348

SUBJECT:

REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE LIMERICK GENERATING STATION, UNITS 1 AND 2, LICENSE RENEWAL APPLICATION (TAC NOS. ME6555 AND ME6556)

Dear Mr. Gallagher:

By letter dated June 22,2011, Exelon Generation Company, LLC submitted an application pursuant to Title 10 of the code of Federal Regulations Part 54 (10 CFR Part 54), to renew the operating licenses for Limerick Generating Station, Units 1 and 2, for review by the U.S. Nuclear Regulatory Commission (NRC or the staff). The staff is reviewing the information contained in the license renewal application and has identified, in the enclosure, areas where additional information is needed to complete the review.

These requests for additional information were discussed with Christopher Wilson, and a mutually agreeable date for the response is within 30 days from the date of this letter. If you have any questions, please contact me at 301-415-3733 or bye-mail at Robert.Kuntz@nrc.gov.

Sincerely, IRA!

Robert F. Kuntz, Senior Project Manager Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-352 and 50-353

Enclosure:

Requests for Additional Information cc w/encl: Listserv DISTRIBUTION: See following page ADAMS Accession No.:ML12024a231 OFFICE LA:RPB1:DLR PM:RPB1 :DLR BC: RPB1: DLR PB1:DLR NAME Y. Edmonds R. Kuntz D. Morey R. Kuntz E 02/03/12 02/03/12 02/06/12 02/16/12 OFFICIAL RECORD COpy