Pre-PEO Implementation

After an extended license is granted, the licensee is responsible for meeting all the commitments made during the license renewal (LR) licensing process. The individual commitments are what have been agreed to between the licensee and the United States Nuclear Regulatory Commission (U.S. NRC) and can be found in the license renewal application (LRA) and other LR-related docketed correspondence. These LR commitments are typically summarized in an appendix of the safety evaluation report (SER) documenting the approval of the renewed license. Commitments can be specific to Aging Management Programs(AMPs) but can also be independent of any AMP.

Part of this Pre-Period of Extended Operation (PEO) Implementation task is to perform all the inspections and document updates that were committed to be performed prior to entry into the PEO. The final portion of this implementation task includes providing the documented objective evidence that these inspections/commitments are complete, which the regulator will review during their (U.S. NRC) Pre-PEO Inspections.

This can be a very time-intensive and laborious task and should not be taken lightly. Most pre-PEO inspections can be performed within 5-10 years of entry into the PEO. It is best to take advantage of the time allotted for these inspections and document updates, so that there is not an excessive backlog of work that needs to be done just prior to the PEO. The Pre-PEO Implementation task includes (but is not limited to) plant-specific inspections, program implementing documentation, specialty contractor tasks and preparations for regulatory inspections.

Plant-Specific Inspections

Plant-specific inspections vary from site-to-site, based on commitments, but generally include a substantial number of visual or non-destructive examinations (NDE) of individual plant components. Each site will have their own list of specific inspection requirements. Below is a table of some of the more standard inspections required for LR. See EPRI References by AMP table for useful references.

Inspection Type	Description	Scope of Inspections
One-Time Inspections (OTI)	Typically visual inspections of internal surfaces when components are opened, or they are ultrasonic (UT) thickness tests taken from external surfaces. Both these inspection methods can be used to determine loss of material. If cracking is an aging effect requiring management, then other NDE techniques that can identify cracking need to be used (e.g. enhanced visual test (EVT), dye penetrant test (DPT), UT, radiography test (RT), magnetic particle test (MT))	200-400 inspections of individual components
Selective Leaching Inspections (if applicable)	Typically visual inspections of the wetted surfaces of the component. Cast iron materials require an additional mechanical test (scratching or scraping). Some destructive tests will likely be required, in which the component is removed from the system and sent to a lab where it is bisected and analyzed for the presence of selective leaching.	60-80 inspection of components that are susceptible to selective leaching
Buried Piping Inspections	A site will likely have an existing Underground Piping Program per NEI 09-14, “Guideline for the Management of Underground Piping and Tank Integrity”, but LR requirements may be in addition to those inspections required by the Nuclear Energy Institute (NEI) program.	Dependent on the amount/linear feet of buried components at the site
American Society of Mechanical Engineers (ASME) Class I Small-Bore Inspections	Volumetric NDE exams to identify potential cracking in ASME Class 1 small-bore piping that is not inspected per the ASME Section XI code requirements. These exams include socket welded components, which are not typically inspected via volumetric means, due to the geometry of the socket. Therefore, special volumetric techniques for socket welded locations are needed.	Class 1 small-bore piping not inspected per ASME Section XI
Fire Water Inspections	System pressure monitoring, system flow testing, periodic flushing, wall thickness evaluations (UT or visual), and testing of sprinkler heads.	Fire Water System
Internal Tank Inspections	Focused on the condition of the internal surfaces of the tank, and in particular, the floor of the tank, which may be on a pedestal or concrete base, or buried. This may require draining and cleaning of the tank (which can be a very complex and expensive task) in order to perform these UT exams.	Tanks in scope
Internal Coating/Linings Inspections	Internal surfaces of some components can be coated or lined to help prevent age-related degradation. However, operating experience (OE) has shown that these coating/linings can sometimes become detached from the internal surface and can cause flow blockage or damage to down-stream components. Inspections of this type require the system to be opened to inspect the condition of these coatings/linings.	In scope coated or lined internal surfaces
External Surfaces inspections	Components that may be subject to leakage from external sources and/or condensation may require inspection to ensure no substantial external degradation is occurring. This may include some under-insulation inspections.	Susceptible components
Civil/Structural inspections	Area walkdowns to check for structural degradation effects, including structural bolting, on a five-year interval. Groundwater sampling may be required on a periodic basis to assess the impact of groundwater chemistry on below grade concrete.	Area walkdowns
Electrical Cable Inspections and Testing	In-scope cables in a wide variety of voltage levels, and also would include adverse local environment (ALE) inspections. These ALE inspections look for areas where elevated localized temperatures or localized elevated radiation levels may cause adverse cable insulation degradation. Cables in these ALE areas are then more closely inspected for cable insulation degradation. There are also a number of testing regimens that can be used to test cable insulation integrity. One degradation mechanism in particular is water-treeing, which can happen to cables that are submerged for long periods of time.	In scope cables
Cable Connector and Metal Enclosed Bus (MEB ) Inspections	Visual inspections of cable connections and inside of MEBs may be required, to look for degradation mechanisms like overheating, corrosion, joint loosening, etc.	Cable connection and MEB
Existing Programs	Programs at sites are already well-developed, implemented, and in use, such as Steam Generators, ASME Section XI programs, Water Chemistry, Fuel Oil Chemistry, etc. Inspections required by those programs will continue into the PEO but are not typically considered additional LR inspections.	Per exisiting program

Program Implementing Document Updates

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Each AMP has various site-specific implementing documents, where the requirements within the AMP are included in site procedures/work plans. Details within the AMPs or the commitments will typically describe which implementing documents need to be revised or created.

• Procedure enhancements: typically about 200-250 implementing documents will need to be updated to reflect the requirements/commitments agreed to in the LRA/SER.
• New procedure generation: new procedures may need to be created if there is no other specific document available to control the requirements/commitments in the LRA/SER.
• Preventive Maintenance (PM) enhancements/creation for on-going inspections: this is needed for inspections that will be repeated over time (e.g. monthly, yearly, every refueling cycle, every 10 years, etc.)
• Work Order (WO) creation and planning for various one-time inspections: the one-time inspections will typically require an individual WO to be created and managed within the site’s Work Management and scheduling process. There can be on the order of 1000 individual one-time inspections across all LR programs.

Typical Specialty Contractor Tasks

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Some of the required inspections or evaluations may require a specialty contractor to perform, based on special technical expertise, or by the Original Equipment Manufacturer (OEM) due to proprietary information.

• Fatigue analysis, including Environmentally Assisted Fatigue (EAF)
• Flaw Tolerance evaluations
• Major component inspections or evaluations (Reactor Vessel Internals, Reactor Coolant pumps, Steam Generators, Cast Austenitic Stainless Steel (CASS) components, overhead cranes)
• Vessel surveillance (Fluence projections, sample testing, Pressurized Thermal Shock (PTS) and Upper Shelf Energy (USE) evaluations).
• Environmental Qualification (EQ) updates. Components within the EQ program have a calculated qualified life, and with extensions of the operating license, these need to be reviewed and amended, as necessary, to match the new license period.

Preparation for Pre-PEO Regulatory Inspections

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Each site will need to prepare for the pre-PEO regulatory inspections. There will be a large amount of documentation that the regulator will likely review in these inspections, and it will be important to provide succinct summaries of each program and commitment, along with complete objective evidence to demonstrate compliance with all program requirements and commitments. The following list includes some of the typical topics or information needed to be prepared for the pre-PEO inspections:

• AMP Owner selection and training: Each individual AMP will likely need an AMP Owner who has overall responsibility for the implementation of that AMP. These individuals are typically plant personnel who may not have been involved in the actual LR activities, so they may need some training to come up-to-speed with the requirements within their respective AMPs. The regulator is likely to interview AMP Owners during the pre-PEO inspections.
• Generate a Completion Binder for each program and/or commitment: provide objective evidence demonstrating completion of each requirement/commitment, including copies of:
  • Implementing documents that were generated or enhanced. It is ultimately helpful to list individual steps of a procedure or other documentation that specifically meets a commitment.
  • Work Management documentation for each individual inspection with results attached
  • Inspection Summaries: for those programs that use the results of individual inspections as a basis for concluding that aging is managed, (e.g. One-Time Inspection – the results of OTI exams will demonstrate that Water Chemistry is adequately managing aging, or conversely, that periodic inspections may be required).
• Generate a Commitment Closure Summary for each commitment: this can be a subset of a commitment tracking program used by the site, or a specific LR commitment tracker. Either way, each individual commitment will need to be addressed to demonstrate closure. Some commitments have numerous sub-steps, so it is critical that each sub-step be tracked and documented for closure. These Closure Summaries can be either hardcopy or electronic, although electronic is recommended.

Some commitments that continue throughout the PEO may be closed by showing that there are procedures in place to continue to implement the commitment and these procedures are annotated as being LR commitments. An example is the Water Chemistry Program which was in existence since initial plant start and will continue until the plant is shutdown.

• Peer Review of the closeout documentation: as part of a preparation for the US NRC Pre-PEO Inspections, a site will typically engage a number of peer reviewers to review the documentation and provide feedback on the quality and completeness of that documentation. This needs to be scheduled a few months in advance of the US NRC Inspections, so a site has an opportunity to resolve any issues identified in the peer review.

Regulatory Guidance

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Pre-PEO inspections are driven by applicable national regulatory framework, in the United States by the US NRC Inspection Procedures IP-71003 Series. These inspection procedures (IPs) will provide the licensee the information that the regulator is looking for during their inspections.

Per 10 CFR 54.37(b), after a renewed license is issued, the licensee must also perform annual updates to include newly identified components that would have been subject to aging management review (AMR) or Time Limited Aging Analysis (TLAA). Additional guidance for meeting these requirements is provided by the NRC in RIS-07-16 Rev. 1, Implementation of the Requirements of 10 CFR 54.37(b) for Holders of Renewed Licenses.

Industry Resources

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The NEI License Renewal Task Force (LRTF) meets periodically to exchange information from recent audits and submittals, and to share site experiences and issues.

Boiling Water Reactors Owners Group (BWROG) provides the industry with various forms of assistance and technical input for General Electric BWR plants.

Pressurized Water Reactors Owners Group (PWROG) provides the industry with various forms of assistance and technical input for PWR plants.

Record of Revisions

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Number	Date	Description of Changes
0	6/11/2024	Initial version

License Renewal

Nuclear Regulatory Commission - The US federal government agency that regulates nuclear power plants

License Renewal Application - The document submitted by the plant licensee under 10 CFR 54 to extend the operating license of the plant from 40 to 60 years.

Safety Evaluation Report

Period of Extended Operation - The Period of Extended Operation is the time period between the end of the original plant operating license and the end of the plant renewed license. In US plants, this will typically be 20 years.

Non Destructive Examination

One-Time Inspections - One-time inspections of selected components or structures to verify effectiveness of AMPs monitoring chemistry: water chemistry, fuel oil and lubricating oil.

Ultrasonic Test - A nondestructive test method using ultrasonic waves to determine the thickness of a component and to detect cracks or other degradation.

Enhanced Visual Test

Dye Penetrant Test - A method to detect cracks on external surfaces of components using a liquid dye. Also known as Penetrant Test.

Radiography Test - A nondestructive testing method using X-rays to detect flaws in a component or to measure the component's wall thickness.

Magnetic Particle Test - A nondestructive testing method using a magnetic field to identify shallow surface discontinuities.

Nuclear Energy Institute

American Society of Mechanical Engineers

Operating Experience

Adverse Local Environments - Local environments where the temperature or radiation level is greater than anticipated in the plant design. Typically used when assessing aging of electrical cables.

Metal Enclosed Bus

Aging Management Program

Preventive Maintenance

Work Order - A document used to authorize and control maintenance repairs, inspections, testing, and other work in a nuclear power plant.

Original Equipment Manufacturer

Environmentally Assisted Fatigue - A degradation mechanism given by a reduction in fatigue life in the reactor water environment compared with the in-air environment.

Cast Austenitic Stainless Steel

Pressurized Thermal Shock

Upper Shelf Energy - The temperature at which metal changes from brittle to ductile failure.

Environmental Qualification - A process for ensuring that equipment will be capable of withstanding the ambient conditions that could exist when the specific function to be performed by the equipment is actually called upon to be performed under accident conditions.

United States of America

Aging Management Review

License Renewal Task Force

Boiling Water Reactor Owners Group

Boiling Water Reactor

Pressurized Water Reactor Owners Group

Pressurized Water Reactor