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Federal Register / Vol. 86, No. 124 / Thursday, July 1, 2021 / Proposed Rules
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disclosed in your comment submission.
The NRC will post all comment submissions at https
www.regulations.gov as well as enter the comment submissions into ADAMS.
The NRC does not routinely edit comment submissions to remove identifying or contact information.
If you are requesting or aggregating comments from other persons for submission to the NRC, then you should inform those persons not to include identifying or contact information that they do not want to be publicly disclosed in their comment submission.
Your request should state that the NRC
does not routinely edit comment submissions to remove such information before making the comment submissions available to the public or entering the comment submissions into ADAMS.
II. Background Part 52 of title 10 of the Code of Federal Regulations 10 CFR, Licenses, Certifications, and Approvals for Nuclear Power Plants, subpart B, Standard Design Certifications, presents the process for obtaining standard design certifications. By letter dated December 31, 2016, NuScale Power, LLC, NuScale Power filed its application for certification of the NuScale standard design hereafter referred to as NuScale ADAMS
Accession No. ML17013A229. The NRC
published a notification of receipt of the design certification application DCA in the Federal Register on February 22, 2017 82 FR 11372. On March 30, 2017, the NRC published a notification of acceptance for docketing of the application in the Federal Register 82
FR 15717 and assigned docket number 52048. The preapplication information submitted before the NRC formally accepted the application can be found in ADAMS under Docket No. PROJ0769.
NuScale is the first small modular reactor design reviewed by the NRC.
NuScale is based on a small light water reactor developed at Oregon State University in the early 2000s. It consists of one or more NuScale power modules hereafter referred to as power modules. A power module is a natural circulation light water reactor composed of a reactor core, a pressurizer, and two helical coil steam generators located in a common reactor pressure vessel that is housed in a compact cylindrical steel containment. The NuScale reactor building is designed to hold up to 12
power modules. Each power module has a rated thermal output of 160 megawatt thermal MWt and electrical output of 50 megawatt electric MWe, yielding a total capacity of 600 MWe for 12 power
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modules. All NuScale power modules are partially submerged in one safetyrelated pool, which is also the ultimate heat sink for the reactor. The pool portion of the reactor building is located below grade. The design utilizes several first-of-a-kind approaches for accomplishing key safety functions, resulting in no need for Class 1E safetyrelated power no emergency diesel generators, no need for pumps to inject water into the core for post-accident coolant injection, and reduced need for control room staffing while providing safe operation of the plant during normal and post-accident operation.

18.5.4.2, Evaluation of the Applicants Technical Basis, of the final safety evaluation report ADAMS Accession No. ML20023B605, the NRC found that NuScale Powers proposed staffing level, as described in the DCA Part 7, Section 6, is acceptable. Because Section V, Applicable Regulations, of this proposed rule includes the alternative staffing requirement provisions, staffing table, and appropriate table notes, a future applicant or licensee that references proposed appendix G to 10 CFR part 52
would not need to request an exemption from 50.54m.

III. Regulatory and Policy Issues
B. Incorporation by Reference The proposed Section III.A, Incorporation by reference approval, of appendix G to 10 CFR part 52 lists documents that would be approved by the Director of the Office of the Federal Register for incorporation by reference into this appendix. Proposed Section III.B.2 identifies information that is not within the scope of the design certification and, therefore, is not incorporated by reference into this appendix. This information includes conceptual design information, as defined in 52.47a24, and the discussion of first principles described in the Design Control Document DCD Part 2, Tier 2, Section 14.3.2, Tier 1 Design Description and Inspections, Tests, Analyses, and Acceptance Criteria First Principles.

A. Control Room Staffing Requirements The requirements in 50.54k and 50.54m identify the minimum number of licensed operators that must be on site, in the control room, and at the controls. The requirements are conditions in every nuclear power reactor operating license issued under 10 CFR part 50, Domestic Licensing of Production and Utilization Facilities.
The requirements also are conditions in every combined license COL issued under 10 CFR part 52; however, they are applicable only after the Commission makes the finding under 52.103g that the acceptance criteria in the COL are met.
In a letter to the NRC, dated September 15, 2015 ADAMS Accession No. ML15258A846, NuScale Power proposed that 6 licensed operators would operate up to 12 power modules from a single control room. The staffing proposal would meet the requirements of 50.54k but would not meet the requirements in 50.54m2i because the minimum requirements for the onsite staffing table in 50.54m2i do not address operation of more than two units from a single control room.
The proposal also would not meet 50.54m2iii, which requires a licensed operator at the controls for each fueled unit i.e., 12 licensed operators. Absent alternative staffing requirements, future applicants referencing the NuScale design would need to request an exemption.
In the DCA Part 7, Section 6.2, Justification for Rulemaking, NuScale Power provided a technical basis for rulemaking language that would address control room staffing in conjunction with control room configuration.
NuScale Powers approach is consistent with SECY110098, Operator Staffing for Small or Multi-Module Nuclear Power Plant Facilities, dated July 22, 2011 ADAMS Accession No.
ML111870574. In Chapter 18, Section
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C. Issues Not Resolved by the Design Certification The NRC identified three issues as not resolved within the meaning of 52.63a5. There was insufficient information available for the NRC to resolve issues regarding 1 the shielding wall design in certain areas of the plant; 2 the potential for containment leakage from the combustible gas monitoring system, and 3 the ability of the steam generator tubes to maintain structural and leakage integrity during density wave oscillations in the secondary fluid system, including the method of analysis to predict the thermalhydraulic conditions of the steam generator secondary fluid system and resulting loads, stresses, and deformations from density wave oscillations from reverse flow.
1. Shielding Wall Design As discussed in Section 12.3.4.1.2 of the final safety evaluation report, the NRC found that there were insufficient design details available regarding shielding wall design with the presence of large penetrations, such as the main
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