ML081090479

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Pilgrim April 2008 Evidentiary Hearing - Applicant Exhibit 4, NUREG-1801, Generic Aging Lessons Learned (GALL) Report, Vol. 1, Rev. 1 and Vol. 2, Rev. 1 (Excepts)
ML081090479
Person / Time
Site: Pilgrim
Issue date: 01/30/2005
From:
Division of Regulatory Improvement Programs
To:
NRC/SECY/RAS
SECY RAS
References
50-293-LR, ASLBP 06-848-02-LR, Pilgrim-Applicant-7, RAS J-37
Download: ML081090479 (16)
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Learned (GALL) Report OFFICE OF SECRETARY RULEMAKINGS AND ADJUDICATIONS STAFF Summary Manuscript Completed:. September 2005 Date Published: September 2005 Division of Regulatory Improvement Programs Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

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INTRODUCTION NUREG-1801, "Generic Aging Lessons Learned (GALL) Report," is referenced as a technical basis document in NUREG-1800, "Standard Review Plan for Review of License Renewal Applications for Nuclear Power Plants" (SRP-LR). The GALL Report identifies aging management programs (AMP) that were determined to be acceptable to manage aging effects of systems, structures and components (SSC) in the scope of license renewal, as required'by 10 CFR Part 54, "Requirements for Renewal of Operating Licenses for Nuclear Power Plants."

The GALL Report is comprised of two volumes. Volume 1 summarizes the aging management reviews that are discussed in Volume 2. Volume 2 lists generic aging management reviews (AMRs) of SSCs that may be in the scope of license renewal applications (LRAs) and identifies GALL AMPs that are acceptable to manage the aging effects.

Ifan LRA references the GALL Report as the approach used to manage aging effect(s), the, NRC staff will use the GALL Report as a basis for the LRA assessment consistent with guidance specified in the, SRP-LR.

BACKGROUND Revision 0 of the GALL Report By letter dated March 3, 1999, the Nuclear Energy Institute (NEI) documented the industry's views on howexisting plant programs and activities should be credited for license renewal. The issue can be summarized as follows: To what extent should the staff review existing programs

  • relied on for license renewal in determining whether an applicant has demonstrated reasonable assurance that such programs will be effective in managing the effects of aging on the functionality of structures and components during the period of extended operation? In a staff paper, SECY-99-148, "Credit for Existing Programs for License Renewal," dated June 3, 1999, the staff described options for crediting existing programs and recommended one option that the staff believed would improve the efficiency of the license renewal process.

By staff requirements memorandum (SRM), dated August 27, 1999, the Commission approved the staffs recommendation and directed the staff to focus the staff review guidance in the Standard Review Plan for License Renewal (SRP-LR) on areas where existing programs should be augmented for license renewal. The staff would develop a "Generic Aging Lessons Learned (GALL)" report to document the staffs evaluation of generic existing programs. The GALL Report would document the staffs basis for determining which .existing programs are adequate without modification and which existing programs should be augmented for license renewal. The GALL Report would be referenced in the SRP-LR as a basis for determining the adequacy of existing. programs.

This report builds on a .previous report, NUREG/CR-6490, "Nuclear Power Plant Generic'Aging' Lessons Learned (GALL)," which is a systematic compilation of plant aging information. This

.report extends the information in NUREG/CR-6490 to provide an evaluation of the adequacy of.

aging management programs for license renewal. The NUREG/CR-6490 report was based on information in over 500 documents: Nuclear Plant Aging Research (NPAR) program reports sponsored bythe Office of Nuclear Regulatory Research, Nuclear Management and Resources Council (NUMARC, now NEI) industry reports addressing license renewal for major structures and components, licensee event reports (LERs), information notices, generic letters, and September 2005 I NUREG-1801 Vol. 1, Rev. I

bulletins, The staff has also considered information contained in the reports provided by the Union of Concerned Scientists (UCS) in a letter dated May 5, 2000.

Following the general format of NU REG-0800 for major plant sections except for refueling water, chilled water, residual heat removal, condenser circulating water, and condensate storage system in pressurized water reactor (PWR) and boiling water reactor (BWR) power plants, the staff has reviewed the .aging effects on components and structures, identified the relevant existing programs, and evaluated program attributes to manage aging effects for license renewal. This report was prepared with the technical assistance of Argonne National Laboratory and Brookhaven National Laboratory. As directed in the SRM, this report has the benefit of the experience of the staff members who conducted the review of the initial license renewal applications. Also, as directed in the SRM, the staff has sought stakeholders' participation in the development of this report. The staff held many public meetings and workshops to solicit input from the public. The staff also requested comments from the public on the draft improved license renewal guidance documents, including the GALL Report, in the Federal Register Notice, Vol. 65, No. 170,. August 31,.20Q0. The staff s.analysis of stakeholder comments is documented in NUREG-1739. These documents can be found on-line at:

http://www.nrc.gov/reading-rm/doc-collections/.

Revision I of the GALL Report The GALL Report has been referenced in numerous license renewal applications (LRA) as a basis for aging management reviews to satisfy the regulatory criteria contained in 10 CFR Part 54, "Requirements for Renewal of Operating Licenses for Nuclear Power Plants," Section 54.21, "Contents of application - technical information." Based on lessons learned from these reviews, and other public input, including industry comments, the NRC staff proposed changes to the GALL Report to make the GALL Report more efficient. A preliminary version of Revision 1 of the GALL Report was posted on the NRC public web page on September 30, 2004. The draft revisions of GALL Vol. 1 and Vol. 2 were further refined and issued for public comment.on January 31, 2005. In addition, the staff also held public meetings with stakeholders to facilitate dialog and to discuss comments. The staff subsequently took into consideration comments received (see NUREG-1 832) and incorporated its dispositions into the' September 2005 version of the GALL Report..

OVERVIEW OF THE GALL REPORT EVALUATION PROCESS The results of the GALL effort are, presented in a table format in the GALL Report, Volume 2.

The table column headings are: Item, Structure and/or Component; Material., Environment; Aging Effect/Mechanism; Aging Management Program (AMP); and Further Evaluation. The staffs evaluation of the adequacy of each generic aging management program in managing certain aging effects for particular structures and components is based on its review of the following 10 program elements in each agingmanagement program:

AMP Element Description

1. Scope of the program The scope of the program should include the specific structures arid components subject to an aging management review.
2. Preventive actions Preventive actions should mitigate or prevent the applicable aging effects.
3. Parameters monitored or Parameters monitored or inspected should be linked to the inspected effects of aging on the intended functions of the particular NUREG-1801 Vol. 1, Rev. 1 2 September 2005

AMP Element Description structure and component.

4. Detection of aging effectss Detection of aging effects should occur before there is a loss of any structure. and component intended function. This includes aspects such as method or technique (i.e., visual, volumetric, surface inspection), frequency, sample size, data collection and timing of hew/one-time inspections to ensure timely detection of aging effects.
5. Monitoring and trending Monitoring and trending should provide for prediction of the extent of the effects of aging and timely corrective or mitigative actions.
6. Acceptance criteria Acceptance criteria, against which the need for corrective action will be evaluated, should ensure that the particular structure and component intended functions aremaintained under all current licensing basis (CLB) design conditions during the period of extended operation.
7. Corrective actions Corrective actions, Including root cause determination and prevention of recurrence, should be timely.
8. Confirmation, process The confirmation process should ensure that preventive actions are adequate and appropriate corrective actions have been completed and are effective.
9. Administrative controls Administrative controls should provide a formal review and approval process.
10. Operating experience Operating experience involving the aging management program, including past corrective actions resulting in program enhancements or additional programs, should provide objective evidence to support a determination that the effects of aging will be -adequately managed so that the structure and component intended functions will be maintained during the period of extended operation.

If, on the basis of its evaluation, the staff determined that a program is adequate to manage certain aging effects for a particular structure or component without change, the "Further Evaluation" entry would indicate that no furth.er evaluation is recornmmnded for license renewal.

Chapter XI of the GALL Report, Volume 2, contains the staffs evaluation of generic aging management programs that are relied on in the GALL Report, such as the ASME Section XI inservice inspection, water chemistry, or structures monitoring program.

APPLICATION OF THE GALL REPORT The GALL Report is a technical basis document to the SRP-LR, which .provides the staff with guidance-in reviewing a license renewal application. The GALL Report should be treated in the same manner as an approved topical report that is generically applicable. An applicant may reference the GALL Report in a license renewal application to demonstrate that the programs at the applicant's facility correspond to those reviewed and approved in the GALL Report.

If an applicant takes credit for a program in GALL, it is incumbent on the applicant to ensure that the plant program contains all the elements of the referenced GALL program. In addition, the conditions at the plant must be-bounded by the conditions for which the GALL program was evaluated. The above verifications must be documented on-site in an auditable form. The applicant must include a certification in the license renewal application that the verifications have been completed.

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September 2bO5 3 NUREG-1801 Vol. 1, Rev. 1

The GALL Report contains one acceptable way to manage aging effects for license renewal. An applicant may propose alternatives for staff review in its.plant-specific license renewal application. Use of the GALL Report is not required, but its use should facilitate both preparation of a license renewal application by an applicant and timely, uniform. review by the NRC staff.

In addition, the GALL Report does not address scoping of structures and components for license renewal. Scoping is plant specific, and the results depend on the plant design and current licensing basis. The inclusion of a certain structure or component in the GALL Report does not mean that this particular structure or component is within the scope of license renewal for all plants. Conversely, the omission of a certain structure or component in the GALL Report does not mean that this particular structure or component is not within the scope of license renewal for any plants.

The GALL Report contains an evaluation of a large number of structures and components that may be in the scope of a typical LRA. The evaluation results documented in the GALL Report indicate that many existing, typical generic aging management programs are adequate to manage aging effects for particular structures or components for license renewal without change. The GALL Report also contains, recommendations on specific areas for which generic existing programs should be augmented (require further evaluation) for license renewal and documents the technical basis for each such determination. In addition, the GALL Report identifies certain SSCs that may or may not be subject to particular aging effects, and for which

  • industry groups are developing generic aging management programs or investigating whether aging management is warranted. To the extent the ultimate generic resolution of such an issue

) will need NRC review and approval for plant-specific implementation, as indicated in a plant-specific FSAR supplement, and reflected-in the SER associated with a particular LR application, an amendment pursuant to 10 CFR 50.90 will be necessary.

In the GALL Report, Volume 1, Tables 1 through 6 are summaries of the aging management review. These tables contain the same information as Tables 3.1-1 to 3.6-1, respectively, in the SRP-LR. These tables also include additional seventh and eighth columns that identify the related generic item and unique item associated with each structure and/or component (i.e.,

each row in the AMR tables contained in Volume 2 of the GALL Report). A locator for the plant systems evaluated in Volume 2 is also provided in the Appendix of Volume 1.

The Appendix of Volume 2 of the GALL Report addresses quality assurance (QA) for aging management programs. Those aspects of the aging management review process that affect the quality of safety-related structures, systems, and components are subject to the QA requirements of Appendix B to 10 CFR Part 50. For nonsafety-related structures and components subject to an aging management review, the existing 10 CFR Part 50, Appendix B, QA program may.be used by an applicant to address the elements of the corrective actions, confirmation process, and administrative controls for an aging management program for license renewal.

The GALL Report provides a technical basis for crediting existing plant programs and recommending areas for program augmentation and further evaluation. The incorporation of the GALL Report information into the SRP-LR, as directed by the Commission, should improve the efficiency of the license renewal process and better focus staff resources.

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NUREG-1801 Vol. 1, Rev. I 4 . September 2005

NUREG-1 801, Vol. 2, Rev. 1 Generic Aging Lessons Generic Aging Lessons Learned (GALL) Report Tabulation of Results t

Manuscript Completed: September 2005 Date Published: September 2005 Division of Regulatory. Improvement Programs Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 I* I . ..

  • XI.M2 WATER CHEMISTRY Program Description The main objective of this program is to mitigate damage caused by corrosion and stress corrosion cracking (SCC). The water chemistry program for boiling water reactors (BWRs) relies on monitoring and control of reactor water chemistry based on industry guidelines such asthe boiling water reactor vessel and internals project (BWRVIP)-29 (Electric Power Research Institute [EPRIJ TR-103515) or later revisions. The BWRVIP-29 has three sets of guidelines: one for primary water, one for condensate and feedwater, and one for control rod drive (CRD) mechanism cooling water. The water chemistry program for pressurized water reactors (PWRs) relies on monitoring and control of reactor water chemistry based on industry.guidelines for primary water and secondary water chemistry-such as EPRI TR-105714, Rev. 3 and TR-102134, Rev. 3 or later revisions.

The water chemistry programs are generally effective in removing impurities from intermediate and high flow areas. The Generic Aging Lessons Learned (GALL) report identifies those circumstances in which the water chemistry program is to be augmented to manage the effects of aging for license renewal. For example, the water chemistry program may not be effective in low flow or stagnant flow areas. Accordingly, in certain cases as identified in the GALL Report, verification of the effectiveness of the chemistry control program is undertaken to ensure that significant degradation is not occurring and the component's intended function will be maintained during the extended period of operation. As discussed in the GALL Report for these specific cases, an acceptable verification program is a one-time inspection of selected components at susceptible loca.tions in the system.

Evaluation-and Technical Basis

1. Scope of Program:The program includes periodic monitoring and control of known detrimenta l contaminants such as chlorides, fluorides (PWRs only), dissolved oxygen, and sulfate concentrations below the levels known.to result in loss of material or cracking.

Water chemistry control is in accordance with industry guidelines such as BWRVIP-29 (EPRI TR-1 03515) for water chemistry in BWRs, EPRI TR-1 05714 for primary water chemistry in PWRs, and EPRI TR-102134 for secondary water chemistry in.PWRs:

2. Preventive Actions: The program includes specifications for chemical species, sampling and analysis frequencies, and corrective actions for control of reactor water chemistry.

System water chemistry is controlled to minimize contaminant concentration and mitigate loss of material due to general, crevice and pitting corrosion and cracking caused by SOC.

For BWRs, maintaining high water purity reduces susceptibility to SCOC.

3. ParametersMonitored/inspected"The concentration of corrosive impurities listed in the EPRI guidelines discussed above, which include chlorides, fluorides (PWRs only),

sulfates, dissolved oxygen, and hydrogen peroxide, are monitoredto mitigate degradation of structural materials. Water.quality (pH and conductivity) is also maintained in accordance with the guidance. Chemical species and water quality are monitored by in-process methods or through sampling. The chemical integrity of the samples is maintained and verified to ensure that the method of sampling and storage will not cause a change in the concentration of the chemical species in the samples.

NUREG-1801, Rev. I AI M-1 0 September. 2005

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BWR Water Chemistry: The guidelines in BWRVIP-29 (EPRI TR-1 03515) for BWR reactor water recommend that the concentration of chlorides, sulfates; and dissolved oxygen are monitored and kept below the recommended levels to mitigate corrosion. The two impurities, chlorides and sulfates, determine.the coolant conductivity; dissolved oxygen, hydrogen peroxide, and hydrogen determine electrochemical potential (ECP). The EPRI guidelines recommend that the coolant conductivity and ECP are also monitored and kept below the recommended levels to mitigate SCC and corrosion in BWR plants. The EPRI guidelines in BWRVIP-29 (TR-1 03515) for BWR feedwater, condensate, and control rod drive water recommend that conductivity, dissolved oxygen level, and concentrations of iron and copper (feedwater only) are monitored and kept.below the recommended levels to mitigate SCC. The EPRI guidelines in BWRVIP-29 (TR-103515) also include recommendations for controlling water chemistry in auxiliary systems: torus/pressure suppression chamber; condensate storage tank, and spent fuel pool.

PWR PrimaryWater Chemistry: The EPRI guidelines (EPRI TR-1 05714), for PWR primary water chemistry recommend that the concentration of chlorides, fluorides, sulfates, lithium, and dissolved oxygen and hydrogen are monitored and kept below the recommended levels to mitigate SCC of austenitic stainless steel, Alloy 600, and Alloy 690 components. TR-1 05714 provides guidelines for chemistry control in PWR auxiliary systems such as the boric acid storage tank, refueling water storage tank, spent fuel pool, letdown purification systems, and volume control tank.

PWR Secondary Water Chemistry: The EPRI guidelines (EPRI TR-102134), for PWR secondary water chemistry recommend monitoring and control of chemistry parameters (e.g., pH level, cation conductivity, sodium, chloride, sulfate, lead, dissolved oxygen, iron, copper, and hydrazine) to mitigate steam generator tube degradation caused by denting, intergranular attack (IGA), outer diameter stress corrosioncrackirng (ODSCC), or crevice and pitting corrosion. The.monitoring and control of these parameters, especially the pH level, also mitigates general (for steel components), crevice, and pitting corrosion of the steam generator shell and the balance of plant materials of construction (e.g., steel, stainless steel, and copper).

4. Detection of Aging Effects: This is a mitigation program and does not provide for detection of.any aging effects.

Ir certain cases as identified in the GALL Report, inspection of select components is to be undertaken to -verify the effectiveness of the chemistry control program and to ensure that significant degradation is not occurring and the component intended function will be maintained during the extended period of operation.

5. Monitoring and Trending:The frequency of sampling water chemistry varies (e.g.,

continuous, daily, weekly, or as needed) based on -plant operating conditions and the EPRI water chemistry guidelines. Whenever corrective actions are taken to address an abnormal chemistry condition, increased sampling is utilized to verify the effectiveness of these actions.

6. Acceptance Criteria: Maximum levels for various contaminants are maintained below the system specific limits as indicated by the limits specified in the corresponding EPRI water chemistry guidelines. Any evidence of aging effects or unacceptable water chemistry results is evaluated, the root cause identified, and the condition corrected.

September 2005 X1 M-11I NUREG-1801, Rev. 1

7. CorrectiveActions: When measured water chemistry parameters are outside the specified range, corrective actions are taken to bring the pararneter back within the acceptable range and within the time period specified in the EPRI water chemistry guidelines. As discussed in the appendix to this report, the staff finds the requirements of 10 CFR Part 50, Appendix B, acceptable to address the corrective actions.
8. Confirmation Process:Following corrective actions, additional samples are taken and analyzed to verify that the corrective actions were effective in returning the concentrations of contaminants such as chlorides, fluorides, sulfates, dissolved oxygen, and hydrogen peroxide to within the acceptable ranges. As discussed in the appendix to this report, the staff finds the requirements of 10 CFR Part 50, Appendix B, acceptable to address the confirmation process.
9. Administrative Controls:Site-quality assurance (QA) procedures, review and approval processes, and administrative controls are implemented in accordance with the requirements of 10 CFR Part 50, Appendix B. As discussed in the appendix to this report, the staff finds the requirements of 10 CFR Part 50, Appendix B, acceptable to address administrative controls.
10. OperatingExperience: The EPRI guideline documents have been developed based on plant experience and have been shown to be effective over time with their widespread use. The specific examples of operating experience are as follows:

BWR: Intergranular stress corrosion cracking (IGSCC) has occurred in small- and large-diameter BWR piping made of austenitic stainless steels and nickel-base alloys.

Significant cracking has occurred in recirculation, core spray, residual heat removal (RHR) systems, and reactor water cleanup (RWCU) system piping welds,. IGSCC has also occurred in a number of vessel intemal components, including core shroud, access hole cover, top guide, and core spray spargers (Nuclear Regulatory Commission [NRC]

Bulletin 80-13, NRC Information Notice [IN] 95-17, NRC Generic. Letter [GL] 94-03, and NUREG-.1544). No occurrence of SCC in piping and other components in standby liquid control systems exposed to sodium pentaborate solution has ever been reported (NUREG/CR-6001).

PWR Primary System: The primary pressure boundary piping of PWRs has generally not been found to be affected by SCC because of low dissolved oxygen levels and control of primary water chemistry. However, the potential for SCC exists due to inadvertent introduction of contaminants into the.primary coolant system from unacceptable levels of contaminants in the. boric acid, introduction through the free surface of the spent fuel pool (which can be a natural collector of airborne contaminants), or introduction of oxygen during cooldown (NRC IN 84-18). Ingress of demineralizer resins into the primary system has caused IGSCC of Alloy 600 vessel head penetrations (NRC IN96-11, NRC GL 97-01). Inadvertent introduction of sodium thiosulfate into the primary system has caused IGSCC of steam generator tubes. The SCC has occurred in safety injection lines (NRC INs 97-19 and 84-18), charging pump casing cladding (NRC INs 80-38 and 94-63),

instrument nozzles in safety injection tanks (NRC IN91-05), and safety-related SS piping systems that contain oxygenated, stagnant, or essentially stagnant borated coolant (NRC IN 97-19). Steam generator tubes and plugs and Alloy 600 penetrations have experienced primary water stress corrosion cracking (PWSCC) (NRC INs 89-33, 94-87, 97-88, 90-10, and 96-11; NRC Bulletin 89-01 and its two supplements).

NUREG-1801, Rev. 1 X1 M-1 2 September 2005

PWR Secondary System:.Steam generator tubes have experienced ODSCC, IGA, wastage, and pitting (NRC IN 97-88, NRC GL 95-05). Carbon steel support plates in steam generators have experienced general corrosion. The steam generator shell has experienced pitting and stress corrosion cracking (NRC INs 82-37, 85-65, and 90-04).

Such operating experience has provided feedback to revisions of the EPRI water chemistry guideline documents.

References 10 CFR Part 50, Appendix B, QualityAssurance Criteriafor Nuclear Power Plants, Office of the Federal Register, National Archives and Records Administration, 2005.

BWRVIP-29 (EPRI TR-1 03515), BWR Water Chemistry Guidelines-1993Revision, Normal and Hydrogen Water Chemistry, Electric Power Research Institute, Palo Alto, CA, February 1994.

BWRVIP-79, BWR Water Chemistry Guidelines, Electric Power Research Institute, Palo Alto, CA, March 2000.

BWRVIP-1 30, BWR Water Chemistry Guidelines, Electric Power Research Institute, Palo Alto, CA, October 2000.

EPRI TR-1 02134, PWR Secondary Water Chemistry Guideline-Revision 3, Electric Power Research Institute, Palo Alto, CA, May 1993.

EPRI TR-1 05714, PWR.Primary Water Chemistry Guidelines-Revision3, Electric Power Research Institute, Palo Alto, CA, Nov. 1995.

EPRI TR-1 002884, PWR PrimaryWater Chemistry Guidelines, Electric Power Research Institute, Palo Alto, CA, October 2003.

NRC Bulletin 80-13, Cracking in Core Spray Piping, U.S. Nuclear Regulatory Commission, May 12,1980.

NRC Bulletin 89-01, Failure of Westinghouse Steam GeneratorTube MechanicalPlugs, U.S. Nuclear Regulatory Commission, May 15,1989.

NRC Bulletin 89-01, Supplement 1, Failure of Westinghouse Steam GeneratorTube Mechanical Plugs, U.S. Nuclear Regulatory Commission, November 14,1989.

NRC Bulletin 89-01, Supplement 2, Failureof Westinghouse Steam GeneratorTube Mechanical Plugs, U.S. Nuclear Regulatory Commission, June 28,1991.

NRC Generic Letter 94-03, IntergranularStress Corrosion Cracking of Core Shrouds in Boiling Water Reactors, U.S. Nuclear Regulatory Commission, July 25, 1994.

NRC Generic*Letter 95-05, Voltage-Based RepairCriteria for Westinghouse Steam Generator Tubes Affected by Outside DiameterStress Corrosion Cracking, U.S. Nuclear Regulatory Commission, August 3, 1995.

September 2005 X1 M-1 3 NUREG-1801, Rev. 1

XI.M32 ONE-TIME INSPECTION Program Description The program includes measures to verify the effectiveness of an aging management program (AMP) and confirm the insignificance of an aging effect. Situations in which additional confirmation is appropriate include (a) an.aging effect is not expected to occur but the data is insufficient to rule it out with reasonable confidence;"(b) an aging effect is expected to progress very slowly in the specified environment, but the local environment may be more adverse than that generally expected; or (c) the characteristics of the aging effect include a long incubation period. For these cases, there is to be corifirmatiorn that either the aging effect is indeed not occurring, or the aging effect is occurring very slowly.so as not to affect the componentor structure intended function during the period of extended operation.

A one-time inspection may also be used to provide additional assurance that aging that has not yet manifested itself is not occurring, or that the evidence of aging shows that the aging is so insignificant that an aging management program is not warranted. (Class 1 piping less than or equal to NPS 4 is addressed in Chapter XL. M35, One Time Inspection of ASME Code Class I Small Bore-Piping)

One-time inspections may also be used to verify the system-wide effectiveness of an AMP that is designed to prevent or minimize aging to the extent that it will not cause the loss of intended function during the period of extended operation. For example, effective control of water

. chemistry can prevent some aging effects and minimize others. However, there may be locations that are isolated from the flow stream for extended periods and are susceptible to the gradual accumulation or concentration of agents that promote certain aging effects. This program provides inspections that either verifies that unacceptable degradation is not occurring or trigger additional actions that will assure the intended function-of affected components will be...

maintained during the period of extended-operation.

The elements of the program include (a)determination of the sample size based on an assessment of materials of fabrication, environment, plausible aging effects, and operatirng experience; (b) identification of the inspection locations in the system or component based on the aging effect; (c) determination of the examination technique, including acceptance criteria

-thatwould be effective in managing the aging effect for which the component is examined; and

.(d) evaluation of the need for follow-up'examinations to monitor the progression of aging if age-related degradation is found that could jeopardize an intended function before the end of the period of extended operation.

When evidence of an aging effect is revealed by a one-time inspection, the routine evaluation of the inspection results would identify appropriate corrective actions.

As set forth below, an acceptable verification program may consist of a one-time insipectibn of selected components and susceptible locations in the system. An alternative acceptable program may include routine maintenance or a review of repair or inspection records to confirm that these components have been inspected for aging degradation and significant aging degradation has not occurred. One-time inspection, or any other action or program, created to verify the effectiveness of an AMP and confirm the absence of an aging effect, is to be reviewed by the staff on a plant-specific basis.

September 2005 XI M-105 NUREG-1801, Rev. 1

Evaluation and Technical Basis

1. Scope of Program:The program includes measures to verify that unacceptable degradation is not Occurring, thereby validating the effectiveness of existing AMPs or confirming that there is no need to manage aging-related degradation for the period of extended operation. The structures and components for which one-time inspection is spedified to verify the effectiveness of the AMPs (e.g., water chemistry control, etc.) have been identified in the Generic Aging Lessons Learned (GALL) Report. Examples include the feedwater system components in boiling water reactors (BWRs) and pressurized water reactors (PWRs).
2. Preventive Actions: One-time inspection is an inspection activity independent of methods to mitigate or prevent degradation.
3. ParametersMonitored/Inspected:The program monitors parameters directly related to the degradation of a component. Inspection is to be performed by qualified personnel following procedures consistent with the requirements, of the American Society of Mechanical Engineers (ASME) Code and 10 CFR 50, Appendix B, using a variety of nondestructive examination (NDE) methods, including visual, volumetric, and surface techniques.
4. Detection of Aging Effects: The inspection includes a representative sample of the system population, and, where practical, focuses on the bounding or lead components most susceptible to aging due to time in service, severity of operating conditions, and lowest design margin.

The program will rely on established NDE techniques, includingvisual, ultrasonic, and surface techniques that are performed by qualified personnel following procedures consistent with the ASME Code and 10 CFR Part 50, Appendix B.

The inspection and test techniques will have a demonstrated history of effectiveness in

  • detecting the aging effect of concern. Typically, the one time inspections should be performed as indicated in the following table.

NUREG-1801, Rev. 1 XAM-106 September 2005

Examples of Parameters Monitored or Inspected And Aging Effect for Specific Structure or Component2 Aging Aging Parameter Inspection Effect Mechanism Monitored Method1" Loss of Crevice Wall Thickness Visual (VT-1 or equivalent) and/or Material Corrosion Volumetric (RT or UT)

Loss of Galvanic Wall Thickness Visual (VT-3 or equivalent) and/or Material Corrosion Volumetric (RT or UT)

Loss of General Wall Thickness Visual (VT-3 or equivalent) and/or' Material Corrosion Volumetric (RT'or UT)

Loss of MIC Wall Thickness Visual (VT-3 or equivalent) and/or Material Volumetric (RT or UT)

Loss of Pitting Wall Thickness Visual (VT-1 or equivalent) and/or Material Corrosion Volumetric (RT or UT)

Loss of Erosion Wall Thickness Visual (VT-3 or equivalent) and/or Material Volumetric (RT or UT)

Loss of Fouling Tube Fouling* Visual (VT-3 or equivalent) or Heat Enhanced VT-1 for CASS Transfer Cracking SCC or Cyclic Cracks Enhanced Visual (VT-1 or equivalent)

Loading and/or Volumetric (RT or UT)

Loss of Thermal Loosening of Visual (VT-3 or equivalent)

Preload Effects, Components Gasket Creep and Self-loosening With respect to inspection timing, the population of components .inspected before the end of the current operating term needs to be sufficient to provide reasonable assurance that the aging effect will not compromise any intended function at any time during the period of extended operation. Specifically, inspections need to be completed early enough to ensure that the aging effects that may affect intended functions early in the period of extended operation are appropriately managed. Conversely, inspections need to be timed to allow the inspected components to attain sufficient age to ensure that the aging effects with long incubation periods (i.e., those that may affect intended functions near the'end of the period of extended operation) are identified. Within these constraints, the applicant should schedule the inspection no earlier than 10 years prior to the period of extended operation, and in such a way as to minimize the. impact on plant operations. As a plant will have accumulated at least 30 years of use before inspections under this program begin,.

sufficient times will have elapsed for aging effects, if any, to be manifest.

The examples provided in the table rmay not be appropriate for allrelevant situations. If the applicant chooses to use' an alternative to the recommendations in this table, a technical justification should be provided as an exception to this AMP. This exception should list the AMR line item component, examination technique, acceptance criteria, evaluation standard and a description of the justification.

10 Visual inspection may be used only when the inspection methodology examines the surface potentially experiencing the aging effect.

September 2005 XI M-107 NUREG-1801, Rev. 1

5. Monitoring and Trending: The program provides for increasing of the inspection sample size and locations in the event that aging effects are detected. Determination of the sample size is based on an assessment of materials of fabrication, environment, plausible aging effects, and operating experience. Unacceptable inspection findings are evaluated in accordance with the site corrective action process to determine the need for subsequent (including periodic) inspections and for monitoring and trending the results.
6. Acceptance Criteria:Any indication or relevant conditions of degradation detected are evaluated. For example, the ultrasonic thickness measurements are to be compared to predetermined limits, such as the design minimum wall thickness for piping.
7. Corrective Actions: Site quality assurance (QA) procedures, review and approval processes, and administrative controls are implemented in accordance with the requirements of 10 CFR Part 50, Appendix B. As discussed in the appendix to this report, the staff finds the requirements of 10 CFR Part 50, Appendix B, acceptable to address the corrective actions, confirmation process, and administrative controls.
8. Confirmation Process:See Item 7, above.
9. Administrative Controls: See Item 7, above.
10. OperatingExperience: This program applies to potential aging effects for which there are currently no operating experience indicating the need for an aging management program. Nevertheless, the elements that comprise these inspections (e.g., the scope of the inspections and inspection techniques) are consistent with industry practice.

References 10 CFR Part 50, Appendix B, QualityAssurance Criteriafor Nuclear Power Plants, Office of the Federal Register, National Archives and Records Administration, 2005.

10 CFR 50.55a, Codes and Standards;Office of the Federal Register,- National Archives and Records Administration, 2005.

ASME Section XI, Rules for Inservice Ihspection of NuclearPower Plant Components, ASME Boiler and Pressure Vessel Code, 2001 edition including the 2002 and 2003 Addenda, American Society of Mechanical Engineers, New York, NY.

.2 NUREG-1801, Rev. 1 XI M-108 September-2005

N XI.M.34 BURIED PIPING AND TANKS INSPECTION Program Description The program- includes (a) preventive measures to mitigate corrosion, and (b) periodic inspection to manage the effects of corrosion. on the pressure-retaining capacity of buried steel piping and tanks. Gray castiron, which is included under the definition of steel, is also subject to a loss of material due to selective leaching, which is an aging effect managed under Chapter XI.M33, "Selective Leaching of Materials."

Preventive measures are in accordance with standard industry practice for maintaining external coatings and wrappings' Buried piping and tanks are inspected when they are excavated during maintenance and when a pipe is dug up'and inspected for any reason.

'This program is an acceptable option to manage buried piping and tanks, except further evaluation is required for the program element/attributes of detection of aging effects (regarding inspection frequency) and operating experience.

Evaluation and Technical Basis

1. Scope of Program:The program relies on preventive measures such as coating, wrapping and periodic inspection for loss of material caused by corrosion of the external surface of buried steel piping and tanks. Loss of material in these components, which may be exposed to aggressive soil environment, is caused by general, pitting, and crevice corrosion, and microbiologically-influenced corrosion (MIC). Periodic inspections are performed when the components are excavated for maintenance or for any other reason.

The scope of the program covers buried components that are within the scope of license renewal for the plant.

2. Preventive.Actions: Inaccordance with industry practice, underground piping and tanks are coated during installation with a protective coating system, such as coal tar enamel with a fiberglass wrap and a kraft paper outer wrap, a polyolifin tape coating, or a fusion bonded epoxy coating to protect the piping from contacting the aggressive soil environment.
3. ParametersMonitored/inspected:The program monitors parameters such as coating and wrapping integrity that are directly related to corrosion damage of the external surface of buried steel piping and tanks. Coatings and wrappings are inspected by visual techniques. Any evidence of damaged wrapping or coating defects, such as coating perforation, holidays, or other damage, is an indicator of possible corrosion damage to the external surface of piping and tanks.
4. Detection of Aging Effects: Inspections performed to confirm that coating and. wrapping are intact are an effective method to ensure that corrosion of external surfaces has not occurred and the intended function is maintained. Buried piping and tanks are opportunistically inspected whenever they are excavated during maintenance. When opportunistic, the inspections are performed in areas with the highest likelihood of corrosion problems, and in areas with a history of corrosion problems, within the areas made accessible to support the maintenance activity.

September 2005 Xl M-111 NUREG-1801, Rev. 1

The applicant's program is to be evaluated for the extended period of operation. It is anticipated that one or more opportunistic inspections may occur within a ten-year period.

Prior to-.entering the period of extended operation, the applicant is to verify that there is at least ohe opportunistic or focused inspection is performed within the past ten years. Upon entering the period of extended operation, the applicant is to perform a focused inspection within ten years, unless an .opportunistic inspection occurred within this ten-year period.

Any credited inspection should be performed in areas with the highest likelihood of corrosion problems, and in areas with a history of corrosion problems.

5. Monitoring and Trending: Results of previous inspections are used to identify susceptible locatiorns.
6. Acceptance Criteria: Any coating and wrapping degradations are reported and evaluated according to site corrective actions procedures.
7. CorrectiveActions: The site corrective actions program, quality assurance (QA) procedures, site review and approval process, and administrative controls are implemented in accordance with the requirements of 10 CFR Part 50, Appendix B. The staff finds the r'equirements of 10 CFR Part 50, Appendix B, acceptable to address the corrective actions, -confirmation process, and .administrative controls.
8. Confirmation Process:See Item 7, above.
9. Administrative Controls:See Item 7, above.
10. OperatingExperience: Operating experience shows that the program described here is effective in managing corrosion of external surfaces of buried steel piping and tanks.

However, -because the inspection frequency is plant-specific and depends on the plant operating experience, the applicant's plant-specific operating experience is further evaluated for the -extended period of operation.

References 10 CFR Part 50, Appendix B, QualityAssurance Criteriafor Nuclear Power Plants, Office of the Federal Register, National Archives and Records Administration, 2005.

NUREG-1801, Rev. I X1 M-1 12 September 2005

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