ML100360085

Response to Request for Additional Information for the Review of the Kewaunee Power Station License Renewal Application-Aging Management Review/Aging Management Program

ML100360085
Person / Time
Site:	Kewaunee
Issue date:	02/02/2010
From:	Price J Dominion Energy Kewaunee
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
10-033
Download: ML100360085 (17)

Text

Dominion Energy Kewaunee, Inc.

ilil I )olllinion Boulevard, Clcn Allen, \;\ 2;"1,(

Fp-bruary 2, 2010 United States Nuclear Regulatory Commission Serial No.: 10-033 Attention: Document Control Desk LR/MWH RO Washington, DC 20555-0001 Docket No.: 50-305 License No.: DPR-43 DOMINION ENERGY KEWAUNEE, INC.

KEWAUNEE POWER STATION RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE KEWAUNEE POWER STATION LICENSE RENEWAL APPLICATION*

AGING MANAGEMENT REVIEW/AGING MANAGEMENT PROGRAM By letter dated January 4,2010 (reference 1), the NRC provided a request for additional information regarding the aging management review results included in the license renewal application (LRA) for Kewaunee Power Station (KPS) (reference 2). The NRC staff indicated that responses to each request for additional information (RAls) are needed to complete the review of the KPS LRA. Attachment 1 to this letter provides the Dominion Energy Kewaunee, Inc. (DEK) responses to each of the RAls submitted by the NRC staff in reference 1.

By letter dated August 17, 2009 (reference 3), DEK committed to provide a final response to RAI 83.2-2 related to the Metal Fatigue of Reactor Coolant Pressure Boundary program. Attachment 2 provides the final response to RAI B3.2--2.

On September 22, 2009, a conference call was conducted between the NRC and DEK to discuss DEK responses to RAls regarding the ASME Section XI Inservice Inspection Aging Management Program (AMP). During the teleconference, the NRC staff indicated that additional information associated with the responses to RAls 82.1.2-1 and 82.1.2-2 (provided by DEK letter dated August 17, 2009 (reference 3)) is required for the staff to complete their evaluation. NRC letter dated October 16, 2009 (reference 4) documents the teleconference and the DEK commitment to supplement the responses to these RAls. Attachment 3 to this letter contains the requested information.

Serial No.10-033 Docket No. 50-305 Page 2 of 4 Should you have any questions regarding this submittal, please contact Mr. Paul C.

Aitken at (804) 273-2818.

Very truly yours, rice sident - Nuclear Engineering COMMONWEALTH OF VIRGINIA COUNTY OF HENRICO The foregoing document was acknowledged before me, in and for the County and State aforesaid, today by J. Alan Price, who is Vice President - Nuclear Engineering of Dominion Energy Kewaunee, Inc. He has affirmed before me that he is duly authorized to execute and file the foregoing document in behalf of that Company, and that the statements in the document are true to the best of his knowledge and belief.

Acknowledged before me this Q.no\.dayof Rbyvcx-r\-i, 2010.

MyCommiss" Ill""\ 'i.O I,:> \J11~ ~_

Notary PdIlc Nary Public COfImoftwI_ of VIrtIIM 37 Attachments:

1. Response to Request for Additional Information Regarding the Kewaunee Power Station License Renewal Application.

2. Final Response to RAI 83.2-2.

3. Supplemental Responses to RAls 82.1.2-1 and 82.1.2-2.

References:

1. Letter from John Daily (NRC) to David A. Heacock (DEK), "Request for Additional Information for the Review of the Kewaunee Power Station License Renewal Application - Aging Management Review/Aging Management Program (TAC No.

MD9408)," dated January 4, 2010.

2. Letter from D. A. Christian (DEK) to NRC, "Kewaunee Power Station Application for Renewed Operating License," dated August 12, 2008. [ADAMS Accession No.

ML082341020]

3. Letter from Stephen E. Scace (DEK) to NRC, "Response to Request for Additional Information for the Review of the Kewaunee Power Station License Renewal

Serial NO.1 0-033 Docket No. 50-305 Page 3 of 4 Application - Aging Management Programs," dated August 17, 2009. [ADAMS Accession No. ML092320093]

4. Notes of Teleconference from Samuel Hernandez (NRC) to Dominion Energy Kewaunee, Inc., "Summary of Conference Call With Dominion Energy Kewaunee, Inc. to Discuss the ASME Section XI Inservice Inspection Aging Management Program (TAC No. MD9408)," dated October 16, 2009. [ADAMS Accession No.

ML092800441 ]

Commitments made in this letter:

1. License Renewal Commitment 41 will be added to LRA Table A6.0-1 consistent with the final response to RAI 83.2-2. The new commitment is proposed to support approval of the renewed operating license, and may change during the NRC review period.

2. License Renewal Commitment 42 will be added to LRA Table A6.0-1 consistent with the supplemental response to RAI 82.1.2-1. The new commitment is proposed to support approval of the renewed operating license, and may change during the NRC review period.

3. License Renewal Commitment 43 will be added to LRA Table A6.0-1 consistent with the supplemental response to RAI 82.1.2-2. The new commitment is proposed to support approval of the renewed operating license, and may change during the NRC review period.

Serial NO.1 0-033 Docket No. 50-305 Page 4 of 4 cc: U.S. Nuclear Regulatory Commission Regional Administrator, Region III 2443 Warrenville Road Suite 210 Lisle, IL 60532-4532 Mr. P. S. Tam, Senior Project Manager U.S. Nuclear Regulatory Commission One White Flint, Mail Stop 08-H4A 11555 Rockville Pike Rockville, MD 20852-2738 Ms. V. Perin Environmental Project Manager U.S. Nuclear Regulatory Commission Mail Stop 0-11 F1 Washington, DC 20555-0001 Mr. John Daily License Renewal Project Manager U.S. Nuclear Regulatory Commission Mail Stop 0-11 F1 Washington, DC 20555-0001 NRC Senior Resident Inspector Kewaunee Power Station N490 Highway 42 Kewaunee, WI 54216 Public Service Commission of Wisconsin Electric Division P.O. Box 7854 Madison, WI 53707 David Hardtke Chairman - Town of Carlton E2334 Lakeshore Road Kewaunee, WI 54216

Serial No.1 0-033 Docket No. 50-305 ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING THE KEWAUNEE POWER STATION LICENSE RENEWAL APPLICATION KEWAUNEE POWER STATION DOMINION ENERGY KEWAUNEE, INC.

Serial No.10-033 Docket No. 50-305 Attachment 1/Page 1 of 5 RAI 3.3.2.1-3

Background

License renewal application (LRA) Table 3.3.1 Item 3.3.1-80 and Standard Review Plan for Review of License Renewal Applications for Nuclear Power Plants Table 3.3-1, 10 80 address the loss of material due to pitting, crevice, and microbiologically influenced corrosion of stainless steel and copper piping, piping components and piping elements exposed to raw water. The applicant proposes to manage this aging process through the use of its aging management program (AMP), "Structures Monitoring Program,"

(LRA 82.1.31). The Generic Aging Lessons Learned (GALL) Report recommends that this aging process be managed through the use of the AMP, "Open Cycle Cooling Water System," (GALL AMP XI.M20). The proposed AMP is not consistent with the AMP proposed by the GALL Report. As a result, the applicant proposes that the aging management review items associated with LRA Item 3.3. 1-80 are consistent with the GALL Report in terms of material, environment, and aging effect however a different AMP is credited (Generic Note E).

In its review of LRA Item 3.3.1-80, the staff noted that there are two items subordinate to this LRA item. These items are sumps in the reactor containment vessels system (LRA table 3.5.2-1) and trash grills anchorage in the intake structure system (LRA table 3.5.2-11). It is clear to the staff that the sumps addressed in Table 3.5.2-1 are structural and that these sumps would not benefit from the aging management activities contained in the open cycle cooling water program other than visual inspection, i.e., activities such as heat exchanger testing are not applicable to sumps. Since the structures monitoring program contains visual inspection procedures which are sufficient to address all aging effects which are applicable to sumps, the staff has no objection to the use of the structures monitoring program to manage this aging. However, it is not clear to the staff that the trash grills anchorage addressed in LRA Table 3.5.2-11 would not benefit from the aging management activities associated with the Open Cycle Cooling Water AMP.

For example, it is not clear to the staff that an accumulation of mussels or clams on these anchorages would not obstruct water flow to the trash grills. Therefore, it is not clear to the staff that these anchors should not be subject to biocide applications and detailed inspections for the presence of biofouling organisms as contained in the Open Cycle Cooling Water AMP.

Request Please provide sufficient information concerning the configuration of the trash grills anchorage to permit the staff to conclude that issues associated with biofouling or other degradation issues addressed by the Open Cycle Cooling Water AMP but not addressed by the Structures Monitoring Program AMP are not significant or propose to manage this aging using the Open Cycle Cooling Water or equivalent AMP.

Serial No.10-033 Docket No. 50-305 Attachment 1/Page 2 of 5 DEK Response The trash grilles and their anchorage are associated with the Intake Structure. As described in the LRA Section 2.4.2.10, the Intake Structure is located approximately 1,600 feet from the shore of Lake Michigan at a water depth of 15 feet. The Intake Structure consists of a submerged cluster of three 22-foot diameter steel inlet cones and trash grilles. The inlet cones are installed with the upper end located one foot above the lake bottom. The trash grilles are located at the top of each cone in a horizontal configuration. The trash grilles are anchored to, and supported by, a reinforced concrete ring foundation that is constructed on the outside perimeter of each inlet cone. The reinforced concrete ring foundation is supported by select riprap laid below the lakebed. The trash grille anchorage consists of stainless steel anchor bolts, with one end embedded in the ring foundation and the other end fastened to the top of the trash grille.

The Structures Monitoring Program, described in LRA Appendix B, Section B2.1.31, manages the aging effects of the inlet cones, the trash grilles, and the trash grille anchorage as indicated in LRA Table 3.5.2-11. The Structures Monitoring Program provides for periodic underwater visual inspection and cleaning of these structural elements. The program inspects for loss of material and the accumulation of bio-fouling, including zebra mussels and other organic macro-fouling. Additionally, since the trash grille anchorage is located on the outside perimeter of the inlet cones, an accumulation of bio-fouling on the anchorages will not obstruct water flow into the trash grilles and inlet cones. Biocide applications would be impractical at this location and would provide no additional benefit beyond the visual inspections performed by the Structures Monitoring Program.

Serial NO.1 0-033 Docket No. 50-305 Attachment 1/Page 3 of 5 RAI 3.3.2.3-6

Background

LRA Tables 3.3.2-3, 3.3.2-8, 3.3.2-9, 3.3.2-20, 3.3.2-21, 3.3.2-22, 3.3.2-25, and 3.3.2-26 contain items which address loss of material due to erosion from the internal or external surfaces of steel piping, piping components, and piping elements and heat exchanger components exposed to raw water. The applicant proposes to manage this aging through the use of its AMP, "Work Control Process," (LRA AMP B2.1.32). The applicant proposes that for the component, material, and environment combination listed, the aging effect being considered is not included in the GALL Report (Generic Note H).

In its review of these items, the staff notes that the portion of the Work Control Process (WCP) AMP being employed is that which claims consistency with the GALL Report AMP, "Inspection of internal Surfaces of Miscellaneous Piping and Ducting." The staff also notes that the program description for the WCP AMP states that it is applicable to "piping, piping components, and ducting." The scope of the GALL Report AMP states that it is also applicable to piping, piping elements, and ducting and components in an internal environment (such as indoor uncontrolled air, condensation, and steam). The staff further noted that some of the components under consideration are heat exchangers exposed to raw water. The staff finally noted that heat exchangers exposed to raw water fall outside the scope of both the WCP AMP and the GALL Report AMP.

The staff has no technical issue with the inclusion of heat exchanger components as the inspection techniques necessary to identify erosion in piping will also identify erosion in heat exchangers. The staff does, however, have an administrative objection to the inclusion of heat exc/7anger components in this AMP. Just as the inclusion of materials beyond the scope of the GALL Report AMP required an exception to the WCP AMP, the inclusion of compone'nts outside the scope of the GALL Report AMP, also requires an exception be taken.

Also during its review of these items, the staff noted that Generic Letter 89-13 applies to some raw water syst,ems. The aging of systems to which Generic Letter 89-13 applies must be managed using the Open Cycle Cooling Water AMP. Based on the information provided, it is readily apparent that most of the components under consideration, e.g.,

drain systems, are outside the scope of Generic Letter 89-13 and that the use of the WCP AMP is acceptable because it contains inspection techniques which will identify loss of material due to erosion. It is not, however, apparent that Generic Letter 89-13 does not apply to all of the components under consideration.

Serial No.10-033 Docket No. 50-305 Attachment 1/Page 4 of 5 Request Please take an exception to the WCP AMP to include heat exchanger components in the scope of the AMP or justify why such an exception is unnecessary and confirm that Generic Letter 89-13 does not apply to any of the components under consideration.

DEK Response The Program Description for NUREG-1801, Generic Aging Lessons Learned (GALL)

Report,Section XI.M38, "Inspection of Internal Surfaces of Miscellaneous Piping and Ducting" states that tine "program consists of inspections of internal surfaces of piping, piping components, ducting, and other components [emphasis added] that are not covered by other aging management programs." The Program Description for the Work Control Process proglram, as described in DEK letter 09-597 dated September 25,2009

[ADAMS ML092710045], provides a consistent description of the Internal Surfaces Monitoring program by stating that the "program will perform visual inspections of piping, piping components, ducting, and other components [emphasis added] fabricated of ... " Since the program description is consistent with the NUREG-1801,Section XI.M38 program description, an exception is not necessary related to the scope of applicable components for this program.

It has been confirmed that the components listed in LRA Tables 3.3.2-3, 3.3.2-8, 3.3.2-9, 3.3.2-20, 3.3.2-21, 3.3.2-22, 3.3.2-25, and 3.3.2-26 that are: 1) exposed to a raw water environment; and 2) managed for the effects of aging by the Work Control Process program; arE~ not within the scope of NRC Generic Letter 89-13, Service Water System Problems Affecting Safety-Related Equipment.

Serial No.10-033 Docket No. 50-305 Attachment 1/Page 5 of 5 RAI 3.3.2.3-7

Background

LRA Tables 3.3.2-17 and 3.3.2-28 contain items which address loss of material due to general corrosion from the internal and external surfaces of steel components exposed to uncontrolled indoor air. The applicant proposes to manage this aging through the use of its WCP (LRA AMP B2.1.32). The applicant proposes that for the component, material, and environment combination listed, the aging effect being considered is not included in the GALL Report (Generic Note H).

In its review of these items, the staff noted that the aging effect identified by the applicant is applicable for this combination of component, material, and environment.

The staff also noted that the scope of LRA AMP for metallic materials is limited to internal surfaces. ThE' staff further noted that the visual inspections included in the AMP are capable of detecting loss of material due to general corrosion. The staff, therefore, finds the applicant's proposal to manage the loss of material from the internal surfaces of the components under consideration in Item 3.3.2-28 acceptable because the component is within the scope of the AMP and appropriate inspection methods are included in the proposed AMP However, the staff questions the use of the WCP AMP for the management of loss of material from the external surfaces of the compressor included in /tem 3.3.2-17 because external surfaces are not within the scope of the proposed AMP Request Please justify the use' of the WCP AMP for external surfaces or select an AMP which is appropriate for use on external surfaces.

DEK Response As part of the Work Control Process program, the Internal Surfaces Monitoring inspections manage aging effects on the external surface of several subcomponents of the Technical Support Center Ventilation system air conditioning units, including the "Air Conditioning Units (Compressor)" component type, as indicated in LRA Table 3.3.2-17.

These surfaces are considered to be internal surfaces for the purpose of visual inspection because these subcomponents are located inside the air conditioning unit housing, which requires disassembly for access to the subcomponents.

Serial No.1 0-033 Docket No. 50-305 ATTACHMENT 2 FINAL RESPONSE TO RAI 83.2-2 KEWAUNEE POWER STATION DOMINION ENERGY KEWAUNEE, INC.

Serial No.10-033 Docket No. 50-305 Attachment 2/Page 1 of 2 RAI83.2-2

Background

LRA Section B3.2 states that the KPS Metal Fatigue of Reactor Coolant Pressure Boundary program utilizes all three modules of EPRI software FatiguePro to perform cycle counting, cycle**based fatigue (CBF) monitoring, and stress-based fatigue (SBF) monitoring.

In its stress-based fatigue monitoring module, FatiguePro does not use all six components of a transient stress tensor (Sxx, Syy, Szz, Sxy, Syz, Szx) to perform fatigue analysis in accordance with the ASME Section 11/ NB-3200 guidance.

FatiguePro takes simplified approach by producing only one stress component and uses that single stress component for fatigue usage evaluation. NRC Regulatory Issue Summary (RIS) 2008**30, titled "Fatigue Analysis of Nuclear Power Plant Components,"

dated December 16, 2008 (ML083450727), requests that the license renewal applicants that have used this simplified methodology perform confirmatory analyses to demonstrate that the simplified analyses provide acceptable results. In addition, there are multiple occurrences of terminologies "stress-based monitoring" and "SBF" in the body of the LRA. If the plant does not have appropriate stress monitoring capability, use of such terminologies would be misleading.

Request Make appropriate adjustments and corrections regarding the use of the "stress-based monitoring" and "SBF' terminologies, and reliance to the SBF methodology for fatigue usage calculations. This action applies to the entire body of the LRA, including License Renewal Commitment 28.

Identify the items whose CUF values were calculated using FatiguePro or simplified methodology, including the results shown in LRA Tables 4.3-2 and the results embedded in the text (not tabulated). The items that are identified must be reevaluated in accordance with the guidelines described in ASME Section 11/ NB-3200, taking all 6 components of stress into consideration.

DEK Final Respons<<! to RAI 83.2-2 The initial response to RAI 83.2-2, provided in DEK letter 09-469 dated August 17, 2009

[ADAMS ML092320093], stated that the reanalysis results for locations subject to evaluation for environmental effects on fatigue usage in accordance with NUREG/CR-6260, Application of NUREG/CR-5999 Interim Fatigue Curves to Selected Nuclear

Serial NO.1 0-033 Docket No. 50-305 Attachment 2/Page 2 of 2 Power Plant Components," that were initially evaluated using stress-based fatigue (SBF) monitoring methods, would be provided following completion of the reanalysis.

The surge line hot leg nozzle and the charging line nozzle locations identified in NUREG/CR-6260 were evaluated for Kewaunee using stress-based fatigue (SBF) monitoring methods. Reanalysis of these locations in accordance with the guidance in ASME B&PV Code Section III, Subsection NB-3200, is in progress but is not complete.

Therefore, a commitment will be included in the USAR Supplement to require completion of the analysis and confirmation of acceptable results prior to the beginning of the period of extended operation.

The following commitment will be added to LRA Appendix A, USAR Supplement, Table A6.0-1:

r-Item Commitment Source Schedule 41 Perform a fatigue analysis of the surge Letter 10- Prior to the line hot leg nozzle and the charging line 033; Period of nozzle in accordance with ASME B&PV Final Extended Code Section III, Subsection NB-3200 Response to Operation guidance and determine the CUF, RAI B3.2-2.

considering the effects of the reactor coolant environment. Confirm that CUF is less than 1.0 at the end of 60 years of plant operation.

No change to License Renewal Commitment 28 is required.

Serial No.1 0-033 Docket No. 50-305 ATTACHMENT 3 SUPPLEMENTAL RESPONSES TO RAls 82.1.2-1 AND 82.1.2-2 KEWAUNEE POWER STATION DOMINION ENERGY KEWAUNEE, INC.

Serial No.10-033 Docket No. 50-305 Attachment 3/Page 1 of 3 NRC Request Issue #1- Inadequate Sample Size of Small Bore Piping Welds The applicant does not have a separate small-bore piping one-time inspection aging management program as recommended by GALL, but chooses to use its inservice inspection program instead. In its current lSI interval, it selected, based on risk-informed lSI, eight out of 96 Class I small bore welds for volumetric examinations. This is part of the lSI program but the applicant actually proposed to take credit of the eight samples for the small-bore piping one-time inspection. The staff believes the sample size is not adequate and stated the sample size should be about 24 samples (25% of the population). A size significantly less needs to be technically justified for adequacy.

DEK Supplemental Response to RAI 82.1.2-1:

The sample size for small-bore piping examinations within the ASME Section XI Inservice Inspection, Subsections IWB, IWC and IWD program (lSI Program) will be as follows:

For Examination Category B-J, Item No. B9.21, eight ASME Class 1 small-bore circumferential welds will receive volumetric and surface examinations during each 10-year lSI inspection interval during the period of extended operation. As stated in the response to RAI B2.1.2-1, included in DEK letter 09-469 dated August 17, 2009

[ADAMS ML092320093], eight welds are scheduled to be examined in the current inspection interval. Therefore, 24 total weld examinations will be performed prior to the end of the period of extended operation.

The following commitment will be added to LRA Appendix A, USAR Supplement, Table A6.0-1:

Item Commitment Source Schedule 42 For Examination Category B-J, Item Letter 10-033; During each No. B9.21, eight ASME Class 1 Supplemental 10-year lSI small-bore circumferential welds will Response to RAI inspection receive volumetric and surface B2.1.2-1 interval examinations during each 10-year lSI during the inspection interval during the period period of of extended operation. extended operation.

Serial No.10-033 Docket No. 50-305 Attachment 3/Page 2 of 3 NRC Request Issue #2 - Small-Bore Socket Welds Not Addressed The applicant stated that the socket weld issue has been resolved and that the staff accepted using VT-2 and surface examinations. The staffs official position has been what was recommended in GALL Section XI.M35. It recommends a one-time volumetric examination on small bore piping.

The applicant stated that there is no industry demonstrated means of performing volumetric examination to detect cracking at the inside diameter of a socket weld. The NRC staff responded with the following:

• GALL Section XI. M35 recommends one-time volumetric inspection of Class 1 small-bore piping. VT-2 or surface examination is not sufficient.

• The staff understands that there is not yet a qualified UT technique on socket welds.

However, the industry has been working on developing ultrasonic testing (UT) techniques on socket welds and, in many occasions, has been successful. The staff provided a list of utilities that are known to have used the technique which includes Susquehanna, Ginna, Peach Bottom, and Nine Mile. Duane Arnold, whose application is currently under review, has a plan to use UT techniques.

• There are other options available in addressing socket welds. For example, destructively examine a few welds at an opportunistic time, such as pipe replacement during plant modifications.

DEK Supplemental Response to RAI 82.1.2-2:

The original response to RAI 82.1.2-2 is included in DEK letter 09-469 dated August 17, 2009 [ADAMS ML092320093]. The original response is supplemented herein to include a commitment to perform five volumetric examinations of ASME Class 1 socket welds using a qualified, nuclear-industry inspection methodology that can accurately detect and size discontinuities within the specified examination volume, if available. The welds selected for the volumetric examinations will be from the twenty socket welds identified for Inservice Inspection (lSI) Program examination in the fourth inspection interval, as described in the original response to RAI 82.1.2-2. These welds were selected based on susceptibility, inspectability, dose considerations, and operating experience.

One destructive examination will be performed in lieu of the volumetric examinations in the event that a qualified socket weld inspection methodology is not available prior to the period of extended operation.

Serial No.10-033 Docket No. 50-305 Attachment 3/Page 3 of 3 The following commitment will be added to LRA Appendix A, USAR Supplement, Table A6.0-1:

Item Commitment Source Schedule 43 Five volumetric examinations of ASME Letter 10-033; Prior to the Class 1 small-bore socket welds will Supplemental period of be performed using a qualified, Response to extended nuclear-industry, inspection RAI 82.1.2-2 operation.

methodology that can detect and size discontinuities within the specified examination volume, if a qualified methodology becomes available. One destructive examination will be performed in lieu of this inspection in the event that a qualified inspection methodology is not available prior to the period of extended operation.