Risk-Informed, Technology-Inclusive Regulatory Framework for Advanced Reactors

Part 53 establishes requirements for the maintenance of licensing- basis information in subpart I.

Section 53.1500 describes the purpose of the subpart in terms of the definition of licensing-basis information in subpart A. Subpart I is closely tied to the requirements in subpart H, which provides the requirements for contents of applications for the various types of licenses issued under part 53. Subpart I is generally organized into sections dealing with: (1) licensing-basis information that licensees are not authorized to change without NRC approval (e.g., licenses, regulations); and (2) licensing-basis documents that licensees may change provided specified criteria are satisfied (e.g., FSAR, program descriptions). The subpart also captures certain general conditions on licenses and changes to the licenses related to the transfer and termination of licenses.

Section 53.1502 defines specific terms and conditions of licenses. These terms and conditions are equivalent to the regulations in: (1) Sec. 50.54(h) stating that each license is subject to the provisions of the AEA and requirements issued by the Commission; (2) Sec. 50.54(s) stating the actions the Commission will take if it makes a finding that there is not reasonable assurance that adequate protective measures can and will be taken in the event of a radiological emergency; (3) Sec. 50.54(aa) stating that each license is subject to the specified sections of the Federal Water Pollution Control Act; and (4) Sec. 50.54(dd) stating that a holder of an OL or COL may take reasonable actions that depart from the license in a national security emergency.

Section 53.1505(a) serves as an introduction to and overview of the sections that follow on changes to licensing-basis information requiring prior NRC approval, namely the elements of licensing-basis information defined by licenses, orders, and regulations. The related sections within these subparts primarily deal with the process of how a licensee requests and the NRC issues an amendment to a license or issues an order that modifies a license. Another important element of licensing-basis information that a part 53 licensee is not able to change or deviate from without NRC approval is the NRC regulations themselves. Section 53.1505(b) refers to Sec. 53.080 in subpart A that provides the criteria for a licensee or other party to satisfy when requesting an exemption from NRC regulations.

Section 53.1510 is equivalent to Sec. 50.90 and requires that a licensee submit an application to request an amendment to a license. The required assessments that are included within an application to amend a license under part 53 must address the safety criteria and analysis requirements of subparts B and C. As with parts 50 and 52, licensees must include in their applications an analysis of whether the amendment involves no significant hazards consideration using the standards in Sec. 53.1520, which are equivalent to the standards in Sec. 50.92. Although this rulemaking provided an opportunity to revise the terminology related to no significant hazards consideration determinations, which dates to the early 1960s when applications were supported by final hazard summary reports, the NRC is maintaining the same terminology used in part 50 to minimize the need for associated changes in other regulations, guidance, and public notices.

Section 53.1515 establishes requirements for public notices and state consultations associated with the NRC's processing of a license amendment request. This section is equivalent to Sec. 50.91 for the NRC's processes related to applications to amend an OL or COL. Section 50.91(b) stipulates that the Commission will make available to the licensee the name of the appropriate State official designated to receive such amendments. While the Commission intends to continue following this practice, the Commission has not included this administrative matter in part 53. Section 53.1515(b)(3) contains some modifications compared to Sec. 50.91(b)(3) for clarity; these revisions are not intended to revise the substance of the provisions in part 53 compared to part 50.

Section 53.1520 is based on Sec. 50.92. The section continues to use the criteria in Sec. 50.92 for determining that a proposed amendment involves no significant hazards consideration.

Although more specific terms such as event sequence are used throughout part 53, Sec. 53.1520 uses the term “accident” to maintain consistency with the long history of making no significant hazards consideration determinations under part 50.

Section 53.1525 provides requirements for holders of an OL or COL requesting to revise information from a DC rule that was referenced in the initial license application and included in or incorporated by reference into the facility FSAR. In keeping with the current requirements in part 52, the portion of the part 53 facility licensing- basis information obtained from the certified design is divided into two categories. The most significant design information and the ITAAC are certified by rule and designated as “certification information.” The remaining information, which makes up the majority of the design information approved as part of the DC, is not certified by rule and is not considered “certification information.” Part 52 refers to these categories of information as Tier 1 and Tier 2 information, respectively, and refers to a change made to that information on a plant-specific basis as a departure. Under part 52, a departure from Tier 1 information requires an exemption and, for information incorporated into the license, a license amendment.

Part 53 dispenses with the Tier 1 and Tier 2 terminology. Rather, Sec. 53.1525 uses the term “certification information” in place of Tier 1, and a plant-specific departure from the certification information requires both a request for an exemption from the associated DC rule and, for information such as ITAAC incorporated into the license, a license amendment. However, as provided in Sec. 53.1525(c), a plant-specific departure from the information approved by the NRC as part of the DC rule but that is not certification information (i.e., Tier 2 information under part 52) will be assessed using the process and criteria defined in Sec. 53.1550 for changes to a FSAR. An applicant or licensee must identify such a change as a departure from the referenced standard design in the updated FSAR. The process for making a generic change to a certified design is described in the associated section in subpart H.

Section 53.1530 allows the holder of an ML to make changes to the design of the manufactured reactor or procedures as described in a FSAR associated with the ML without requesting a license amendment from the NRC if the change satisfies the criteria in Sec. 53.1550(a)(1) and (2). This section is different than the provisions in Sec. Sec. 52.98 and 52.171 that do not allow any changes to the design of a manufactured reactor without requesting a license amendment. A COL or OL holder who references or uses a manufactured reactor may make changes to the facility or procedures described in an FSAR, including those portions incorporated by reference from the FSAR associated with the ML, using Sec. 53.1550 to determine if a license amendment is required.

Section 53.1535 establishes requirements for license amendments during construction. The section provides the equivalent options and requirements for the holders of a CP as those in Sec. 50.35(b). The regulations allow but do not require the holder of a CP or LWA to request an amendment under Sec. 53.1510 if the licensee desires to obtain NRC approval of a specific design feature or specification. The requirements for obtaining an amendment to a COL to address changes during construction are also provided in Sec. 53.1535. The process differs from the current requirements in part 52 by adopting a requirement that explicitly supports a change process like that described in RG 1.237, “Guidance for Changes During Construction for New Nuclear Power Plants Being Constructed Under a Combined License Referencing a Certified Design Under 10 CFR part 52.” Section 53.1535 allows the holder of a COL to proceed at its own risk in making a change during the construction process and requires that licensee to submit a license amendment request no later than 45 days from the date the licensee begins to implement the change or departure requiring NRC approval.

Section 53.1540 serves as an introduction to the sections that follow on changes to licensing-basis information that are primarily under the control of a licensee but for which evaluations are made to determine if a submittal to the NRC requesting approval is required. The section also includes definitions that are applicable when using the processes in Sec. Sec. 53.1545 through 53.1565. The definitions are largely equivalent to those in Sec. 50.59(a) but include some revision to reflect the structure and terminology in other subparts in part 53. For example, the definition of “Change” in Sec. 53.1540(b) addresses a “design feature or related functional design criteria” rather than a “design function,” because the former are defined terms in part 53. Similarly, in Sec. 53.1540(b), the phrase “design bases” from Sec. 50.59(a)(2) is replaced with functional design criteria for SR SSCs.

Section 53.1545 provides the requirements for updating of FSARs. While the process-related requirements under Sec. 53.1545 are largely the same as those in Sec. 50.71, the specifics of information to be updated differ due to the role of PRA, other SREs, or a combination thereof in satisfying the requirements in subparts B and C. Additionally, the use of the risk-informed approach in subpart C will result in some but not all information related to PRA, other SREs, or a combination thereof being in the FSAR or another licensing-basis document and therefore a separate update requirement for PRA, other SREs, or a combination thereof similar to Sec. 50.71(h) is not included in subpart I. Section 53.1545(e) addresses updating of FSARs associated with MLs and includes periodic updates to reflect the added flexibility for ML holders to revise the FSAR associated with the ML under Sec. 53.1530.

Section 53.1239(a)(18) in subpart H and the related references to this requirement for the holders of OLs and COLs requires a description of the PRA, other SREs, or a combination thereof required by Sec. 53.450(a) and its results to be included in FSARs. However, guidance documents are planned to clarify the division of information related to PRA, other SREs, or a combination thereof that must be in the FSAR, in other possible licensing-basis documents, and controlled as plant records subject to inspections and audits. At a minimum, the information from the PRA, other SREs, or a combination thereof that is needed to show compliance with subpart C will be included in the FSAR (e.g., summary of PRA, other SREs, or a combination thereof and analytical results for LBEs). The submittal of voluminous PRA information was initially required under part 52, but that proved to be impractical and was revised in the 2007 revision of part 52. Guidance is being developed to ensure sufficient information is submitted to the NRC to support the licensing process and the NRC's regulatory findings under part 53 or similar applications using the LMP methodology under parts 50 or 52.

Section 53.1545(a)(3) and (4) are based on the inclusion of at least a summary of the results of the PRA, other SREs, or a combination thereof and the related margins to safety criteria in the FSAR and require updates to that information. The routine reporting of these margins also informs application of the criteria for allowing changes without an amendment in the following section (Sec. 53.1550) in subpart I.

Section 53.1550 establishes requirements for evaluating changes to a facility as described in its FSAR. This section provides the equivalent of the requirements in Sec. 50.59 for evaluating changes to an FSAR (as updated) and determining if a license amendment is required to implement a change to a facility or procedures. The evaluation criteria in Sec. 53.1550 reflect the role of the PRA, other SREs, or a combination thereof in the safety analyses under part 53 and include several measures related to the changes in plant risk resulting from a change in the plant design or plant procedures. Examples include criteria that rely on the identification of risk-significant event sequences in accordance with the analysis requirements of Sec. 53.450; exceeding the LBE evaluation criteria as defined in Sec. 53.450; the consideration of potential changes in estimated comprehensive risk metrics that exceed the associated risk performance objectives in the safety criteria in Sec. 53.220; changes to the safety classification of SSCs; and consideration of reductions in defense in depth.

Section 53.1550 includes certain concepts taken from existing guidance for Sec. 50.59 in the criteria related to DBAs and aligns with recently developed industry guidance in NEI 22-05, Revision 0, “Technology Inclusive Risk Informed Change Evaluation (TIRICE).” Specifically, criterion (iv) for changes made to a method of evaluation of DBAs under Sec. 53.450(f) is equivalent to a change in a method of evaluation under Sec. 50.59, and criterion (viii) on assessing if a change creates a possibility for an accident of a different type than previously analyzed in the FSAR is similar to the Sec. 50.59 criterion (v). Criterion (v) in Sec. 53.1550 differs from the corresponding criterion in NEI 22-05 in that it does not include changes to safety classification of SSCs from non-safety related or NSRSS to SR because plant changes introducing new SR SSCs would require a change to technical specifications under Sec. 53.710. Guidance documents will be prepared to address the content of applications for information related to PRA, other SREs, or a combination thereof under part 53, and this guidance will also influence how potential changes in the evaluation of LBEs other than DBAs analyzed under Sec. 53.450(e) are evaluated and reported under criterion (iv).

Sections 53.1560 through 53.1565 in subpart I define the processes for a licensee to evaluate changes to the program documents included in the licensing-basis information submitted to the NRC and to modify such programs without NRC prior approval.

Section 53.1560 includes the requirements for updating program documents included in licensing-basis information and provides the equivalent of FSAR updates for key program documents. The requirements in these sections provide a uniform approach for updating program documents, which correspond to the programs required under subpart F.

Section 53.1565 provides a process for licensees to make changes to program documents included in licensing-basis information without obtaining prior NRC approval. The requirements include several generic criteria that, if not satisfied, will prompt the need for NRC approval of a change to a program document. These generic criteria include whether a change will comply with TS and NRC regulations. Another criterion for evaluating changes to program documents is conforming with program-specific requirements, including NRC-approved program documents with more specific criteria for a particular program, regulations, administrative controls sections of TS, and NRC-approved program documents.

Section 53.1565(d) includes specific criteria for evaluating changes to several program documents that have well established change processes and guidance for licensees under parts 50 and 52. The program documents specifically addressed in the section include quality assurance programs that are equivalent to Sec. 50.54(a), an emergency preparedness program that is equivalent to Sec. 50.54(q), and the security program that is equivalent to Sec. 50.54(p).

Section 53.1570 establishes requirements for the transfer of commercial nuclear plant licenses by providing the equivalent requirements of Sec. 50.80 for the possible transfer of an ESP, CP, OL, or COL. Likewise, Sec. 53.1575 establishes requirements for the termination of an OL or COL by providing the equivalent requirements of Sec. 50.82. Other requirements related to decommissioning and license termination are included in subpart G.

Section 53.1580 establishes requirements for information requests the NRC may send to the various types of licensees and provides requirements that are equivalent to requirements in Sec. 50.54(f). Section 53.1585 provides the requirements that are equivalent to requirements in Sec. 50.100 to address revocation, suspension, modification of licenses, and approvals for cause. Section 53.1590 addresses backfitting requirements by providing requirements that are similar to those in Sec. 50.109.

Section 53.1595 addresses license renewals under part 53 with a simple statement that licenses may be renewed. This section may be expanded through future rulemakings to more fully describe or reference the processes related to requesting and processing applications to renew ESPs, OLs, and COLs issued under part 53.

Part 53 addresses various reporting and administrative requirements in subpart J.

Section 53.1600 explains the organization of the various sections within the subpart related to providing unfettered access to NRC inspectors; maintaining certain records and reporting specified events or conditions; demonstrating compliance with financial qualification requirements and providing specified financial reports; and maintaining financial protections to address potential accidents.

Section 53.1610 establishes requirements for the provision of facilities and unfettered access for inspections. These requirements are equivalent to Sec. 50.70 with only minor changes to provide additional flexibilities and address possible differences related to reactors licensed under part 53 and the possibility that some commercial nuclear plants may not be assigned resident inspectors.

Section 53.1620 provides for maintenance of records and the making of various reports to the NRC. These requirements are largely equivalent to Sec. 50.71. This section is not intended to reflect all provisions in Sec. 50.71; several important requirements in Sec. 50.71 are captured in other sections of part 53. For example, Sec. 53.1545 within subpart I provides requirements that are equivalent to Sec. 50.71(e) for updating FSARs. A reporting requirement related to completion of power ascension testing is added to Sec. 53.1620 to support the assessment of annual fees under 10 CFR part 171, “Annual Fees for Reactor Licenses and Materials Licenses, Including Holders of Certificates of Compliance, Registrations, and Quality Assurance Program Approvals and Government Agencies Licensed by the NRC,” which normally commence upon completion of those testing activities.

Section 53.1630 establishes requirements for immediate notification requirements for operating commercial nuclear plants. These requirements are equivalent to Sec. 50.72 with minor changes to make the reporting criteria technology-inclusive. In addition, a new version of NRC Form 361 (NRC Form 361S) has been created for use by part 53 licensees, but without LWR-specific terminology to ensure technology- inclusiveness. The requirements in

Sec. 53.1630 and the new NRC Form 361S are consistent with changes to Sec. 50.72 proposed to the Commission in SECY-24-0049, “Proposed Rule: Reporting Requirements for Nonemergency Events at Nuclear Power Plants (RIN 3150-AK71; NRC-2020-0036),” to eliminate those nonemergency event reporting criteria that are not important to safety, do not require prompt action from the NRC, or can be tracked using other existing agency processes.

Section 53.1640 addresses the licensee event report system. These requirements are equivalent to Sec. 50.73 with minor changes to make the requirements inclusive of various reactor technologies and to reflect appropriate internal references to other sections in part 53. In addition, NRC Forms 366, 366A, and 366B are revised to include corresponding check boxes for part 53 licensees.

Section 53.1645 requires periodic reporting of the quantity of radionuclides released to unrestricted areas in liquid and gaseous effluents, doses to members of the public, and the results of environmental monitoring. These reporting requirements in part 53 are largely equivalent to those in the TSs required by Sec. 50.36a, “Technical specifications on effluents from nuclear power reactors.” The section also includes an equivalent to the reporting requirement in section IV of appendix I to part 50 if the radiation exposure to a member of the public in any calendar quarter exceeds one-half of the annual design objective.

Section 53.1650 includes a reporting requirement to support safeguards agreements between the United States and the International Atomic Energy Agency (IAEA) and is equivalent to Sec. 50.78.

Sections 53.1660 through 53.1700 address financial requirements and are somewhat different than existing regulations in parts 50 and 52. The part 53 requirements do not include the existing part 50 and 52 requirement for an applicant to demonstrate that it “possesses or has reasonable assurance of obtaining” the funds necessary for construction and operation. Instead, part 53 replaces that requirement with an “appears to be financially qualified” standard similar to the standard in Sec. 70.23(a)(5). Section 53.1670 is entitled “Financial qualifications” and requires applicants other than electric utilities to appear to be financially qualified for the activities for which the license is being sought. The remaining financial reports in part 53 are equivalent to Sec. 50.76 for a change of status, Sec. 50.54(cc) for the filing of a petition for bankruptcy, and Sec. 50.81 for creditor regulations. Part 53 does not contain a requirement for annual financial reports equivalent to Sec. 50.71(b) because these reports are not actively used by the NRC to assess a licensee but could be accessed in the event that the NRC deems it necessary to look into a licensee's financial situation due to events such as a declaration of bankruptcy.

Sections 53.1710 through 53.1730 address financial protection requirements. Section 53.1720 requires insurance to stabilize and decontaminate a plant following an accident. These requirements are taken from Sec. 50.54(w), with the only notable change being the addition of a provision allowing plant-specific estimates of costs to stabilize and decontaminate a plant as an alternative to the $1.06 billion minimum coverage in Sec. 50.54(w). An example of cost estimations that, in part, provided a basis for the requirements in Sec. 50.54(w) is provided in NUREG/CR-2601, “Technology, Safety and Costs of Decommissioning Reference Light Water Reactors Following Postulated Accidents.” Section 53.1730 is equivalent to Sec. 50.57(a)(5) and refers to the requirements in 10 CFR part 140, “Financial Protection Requirements and Indemnity,” related to financial protection requirements and indemnity agreements, including the financial protection requirements of the Price-Anderson Act.