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CFR Part 54 (Rule)

The scope of the Rule (10 CFR Part 54) includes: (1) safety-related SSCs that are relied upon to maintain integrity of the reactor coolant pressure boundary, ensure capability to shut down and maintain a safe shutdown condition, and prevent or mitigate offsite exposures comparable to 10 CFR Part 100 [2]; (2) non-safety- related SSCs whose failure could prevent safety-related functions as noted above; and (3) SSCs relied upon for compliance with regulations (i.e., fire protection, environmental qualification, pressurized thermal shock, anticipated transients without scram, and station blackout).

The LRA identifies reactor systems, structures, or components that would be affected by license renewal; demonstrates that it can manage the adverse effects of aging during the renewal period; and analyzes the environmental effects of extended reactor operation during the renewal term [3]. Applicants wishing to submit a LRA are responsible for preparing a plant-specific LRA that includes both general and technical information. The general information is similar to that provided with the initial plant operating license application. Technical information includes an Integrated Plant Assessment (IPA) [10 CFR Part 54.21(a)

(1)], TLAAs (10 CFR Part 54.3), a supplement to the Final Safety Analysis Report (FSAR), and Technical Specification Changes (10 CFR Part 54.22). Readers should refer to Section 2.4.2 (Chapter 2) of this book for more information on FSAR and Technical Specification requirements.

The IPA identifies and lists structures and components subject to an aging management review (AMR) that perform intended functions without moving parts or without change in configuration or properties (passive) or that are not subject to replacement based on a qualified life or specified period (long-lived). For some passive structures and components within the scope of license renewal, no additional action may be required where an applicant can demonstrate that the existing programs provide adequate aging management throughout the period of extended operation. The containments and seismic Category I structures are identified as components subject to an AMR. Intended functions are those that the in-scope SSCs must be shown to fulfill that would form the basis for including the SSCs within the scope of the Rule. Methods used to identify SSCs subject to an AMR are to be identified. Finally, the applicant must demonstrate that the effects of aging will be adequately managed so that their intended function(s) will be maintained consistent with the CLB for the period of extended operation. Each year following submittal of the LRA and at least three months before the scheduled completion of the NRC review, an amendment to the LRA must be submitted that identifies any changes to the CLB that materially affects the contents of the LRA including the FSAR supplement.

Time Limited Aging Analyses are calculations or analyses that involve SSCs within the scope of the Rule that consider the effects of aging and involve assumptions based on the original 40-year operating term. For license renewal, TLAAs must be: (1) verified to bound the renewal period, (2) reanalyzed (recalculated) to determine if it will bound the renewal period, or (3) the applicant must show that the aging effects encompassed by the calculation will be managed. TLAAs are to be contained or incorporated by reference in the CLB.

As part of the LRA, the applicant is required to provide a supplement to the FSAR that provides a commitment to implement and summary descriptions of the required programs and activities for managing the effects of aging. The FSAR supplement is also required to provide evaluation of TLAAs for the period of extended operation. Technical specification changes or additions, with justification, necessary to manage the effects of aging during the period of extended operation are also to be included as part of the application.

CFR Part 51

In addition to its mission of protecting public health and safety under the AEA, the NRC is charged with protection of the environment in the use of nuclear materials. In 1996, the environmental regulations in 10 CFR Part 51 were revised to improve regulatory efficiency in environmental review for license renewal and codify the findings documented in the Generic Environmental Impact Statement (GEIS) for License Renewal [4]. The GEIS examines the possible environmental impacts that could occur as a result of renewing any commercial NPP license and, to the extent possible, establishes the bounds and significance of these potential impacts.

 
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