Nuclear Regulatory Commission Docket NRC-2026-2047 Proposed Rule

2026-13261: List of Approved Spent Fuel Storage Casks: NAC International, Inc., MAGNASTOR® Storage System, Certificate of Compliance No. 1031, Amendment Nos. 16 and 17 and Revisions to Amendment Nos. 0 Through 16

Comment Period Closed

Public comment closed · opened July 01, 2026.

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Summary

The U.S. Nuclear Regulatory Commission (NRC) is proposing to amend its spent fuel storage regulations by revising the NAC International, Inc. (NAC) MAGNASTOR[supreg] System listing within the "List of approved spent fuel storage casks" to include Amendment Nos. 16 and 17 and revisions to Amendment Nos. 0 through 16 to Certificate of Compliance (CoC) No. 1031. Amendment No. 16 revises the CoC to permit alternate methods for determining the free volume inside a loaded canister and for measuring helium to ensure that Technical Specification limits are met. It also clarifies that mixed loadings of different assembly types or subtypes within a single Transportable Storage Cask are acceptable. Amendment No. 17 and revisions to Amendment Nos. 0 through 16 revise the CoC to incorporate changes to the design basis for the MAGNASTOR[supreg] storage system to correct an error with M5 fuel cladding material yield strength that was introduced in CoC No. 1031, Amendment No. 14 and the associated revisions to Amendment Nos. 0 through 13.

The agency’s own summary, as published.

The rule, in full

2,887 words as published, July 01, 2026. View the original →

Federal Register, Volume 91 Issue 125 (Wednesday, July 1, 2026) [Federal Register Volume 91, Number 125 (Wednesday, July 1, 2026)] [Proposed Rules] [Pages 39900-39903] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 2026-13261] ======================================================================== Proposed Rules Federal Register ________________________________________________________________________ This section of the FEDERAL REGISTER contains notices to the public of the proposed issuance of rules and regulations. The purpose of these notices is to give interested persons an opportunity to participate in the rule making prior to the adoption of the final rules. ======================================================================== Federal Register / Vol. 91, No. 125 / Wednesday, July 1, 2026 / Proposed Rules [[Page 39900]] ======================================================================= ----------------------------------------------------------------------- NUCLEAR REGULATORY COMMISSION 10 CFR Part 72 [NRC-2026-2047] RIN 3150-AL68 List of Approved Spent Fuel Storage Casks: NAC International, Inc., MAGNASTOR[supreg] Storage System, Certificate of Compliance No. 1031, Amendment Nos. 16 and 17 and Revisions to Amendment Nos. 0 Through 16

Agency

Nuclear Regulatory Commission.

Action

Proposed rule. -----------------------------------------------------------------------

Summary

The U.S. Nuclear Regulatory Commission (NRC) is proposing to amend its spent fuel storage regulations by revising the NAC International, Inc. (NAC) MAGNASTOR[supreg] System listing within the ``List of approved spent fuel storage casks'' to include Amendment Nos. 16 and 17 and revisions to Amendment Nos. 0 through 16 to Certificate of Compliance (CoC) No. 1031. Amendment No. 16 revises the CoC to permit alternate methods for determining the free volume inside a loaded canister and for measuring helium to ensure that Technical Specification limits are met. It also clarifies that mixed loadings of different assembly types or subtypes within a single Transportable Storage Cask are acceptable. Amendment No. 17 and revisions to Amendment Nos. 0 through 16 revise the CoC to incorporate changes to the design basis for the MAGNASTOR[supreg] storage system to correct an error with M5 fuel cladding material yield strength that was introduced in CoC No. 1031, Amendment No. 14 and the associated revisions to Amendment Nos. 0 through 13.

Dates

Submit comments by July 31, 2026. Comments received after this date will be considered if it is practical to do so, but the NRC is able to ensure consideration of only comments received on or before this date.

Addresses

Submit your comments, identified by Docket ID NRC-2026-2047, at https://www.regulations.gov. If your material cannot be submitted using https://www.regulations.gov, call or email the individual listed in the FOR FURTHER INFORMATION CONTACT section of this document for alternate instructions. Do not include any personally identifiable information (such as name, address, or other contact information) or confidential business information that you do not want publicly disclosed. All comments are public records; they are publicly displayed exactly as received, and will not be deleted, modified, or redacted. Comments may be submitted anonymously. Follow the search instructions on https://www.regulations.gov to view public comments. You can read a plain language description of this proposed rule at https://www.regulations.gov/docket/NRC-2026-2047. For additional direction on obtaining information and submitting comments, see ``Obtaining Information and Submitting Comments'' in the SUPPLEMENTARY INFORMATION section of this document.

For Further Information Contact

Caylee Kenny, Office of Nuclear Material Safety and Safeguards, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001; telephone: 301-415-7150, email: [email protected].

Supplementary Information

Table of Contents I. Obtaining Information and Submitting Comments II. Rulemaking Procedure III. Background IV. Plain Writing V. Regulatory Planning and Review VI. Availability of Documents

A. Obtaining Information

Please refer to Docket ID NRC-2026-2047 when contacting the NRC about the availability of information for this action. You may obtain publicly available information related to this action by any of the following methods: Federal Rulemaking Website: Go to https:// www.regulations.gov and search for Docket ID NRC-2026-2047. Address questions about NRC dockets to Helen Chang, telephone: 301-415-3228, email: [email protected]. For technical questions contact the individual listed in the FOR FURTHER INFORMATION CONTACT section of this document. NRC's Agencywide Documents Access and Management System (ADAMS): You may obtain publicly available documents online in the ADAMS Public Documents collection at https://www.nrc.gov/reading-rm/ adams.html. To begin the search, select ``Begin ADAMS Public Search.'' For problems with ADAMS, please contact the NRC's Public Document Room (PDR) reference staff at 1-800-397-4209, at 301-415-4737, or by email to [email protected]. For the convenience of the reader, instructions about obtaining materials referenced in this document are provided in the ``Availability of Documents'' section. NRC's PDR: The PDR, where you may examine and order copies of publicly available documents, is open by appointment. To make an appointment to visit the PDR, please send an email to [email protected] or call 1-800-397-4209 or 301-415-4737, between 8 a.m. and 4 p.m. eastern time, Monday through Friday, except Federal holidays.

B. Submitting Comments

The NRC encourages electronic comment submission through the Federal rulemaking website (https://www.regulations.gov). Please include Docket ID NRC-2026-2047 in your comment submission. The NRC cautions you not to include identifying or contact information that you do not want to be publicly 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 [[Page 39901]] submissions available to the public or entering the comment into ADAMS.

II. Rulemaking Procedure

Because the NRC considers this action to be non-controversial, the NRC is publishing this proposed rule concurrently with a direct final rule in the Rules and Regulations section of this issue of the Federal Register. The direct final rule will become effective on September 14, 2026. However, if the NRC receives any significant adverse comment by July 31, 2026, then the NRC will publish a document that withdraws the direct final rule. If the direct final rule is withdrawn, the NRC will address the comments in a subsequent final rule. In general, absent significant modifications to the proposed revisions requiring republication, the NRC will not initiate a second comment period on this action in the event the direct final rule is withdrawn. A significant adverse comment is a comment where the commenter explains why the rule would be inappropriate, including challenges to the rule's underlying premise or approach, or would be ineffective or unacceptable without a change. A comment is adverse and significant if: (1) The comment opposes the rule and provides a reason sufficient to require a substantive response in a notice-and-comment process. For example, a substantive response is required when: (a) The comment causes the NRC to reevaluate (or reconsider) its position or conduct additional analysis; (b) The comment raises an issue serious enough to warrant a substantive response to clarify or complete the record; or (c) The comment raises a relevant issue that was not previously addressed or considered by the NRC. (2) The comment proposes a change or an addition to the rule, and it is apparent that the rule would be ineffective or unacceptable without incorporation of the change or addition. (3) The comment causes the NRC to make a change (other than editorial) to the rule, CoC, or technical specifications. For a more detailed discussion of the proposed rule changes and associated analyses, see the direct final rule published in the Rules and Regulations section of this issue of the Federal Register.

III. Background

Section 218(a) of the Nuclear Waste Policy Act of 1982, as amended, requires that ``[t]he Secretary [of the Department of Energy] shall establish a demonstration program, in cooperation with the private sector, for the dry storage of spent nuclear fuel at civilian nuclear power reactor sites, with the objective of establishing one or more technologies that the [Nuclear Regulatory] Commission may, by rule, approve for use at the sites of civilian nuclear power reactors without, to the maximum extent practicable, the need for additional site-specific approvals by the Commission.'' Section 133 of the Nuclear Waste Policy Act states, in part, that ``[t]he Commission shall, by rule, establish procedures for the licensing of any technology approved by the Commission under Section 219(a) [sic: 218(a)] for use at the site of any civilian nuclear power reactor.'' To implement this mandate, the Commission approved dry storage of spent nuclear fuel in NRC-approved casks under a general license by publishing a final rule that added a new subpart K in part 72 of title 10 of the Code of Federal Regulations (10 CFR) entitled ``General License for Storage of Spent Fuel at Power Reactor Sites'' (55 FR 29181; July 18, 1990). This rule also established a new subpart L in 10 CFR part 72 entitled ``Approval of Spent Fuel Storage Casks,'' which contains procedures and criteria for obtaining NRC approval of spent fuel storage cask designs. The NRC subsequently issued a final rule on November 21, 2008 (73 FR 70587), that approved the NAC MAGNASTOR[supreg] System design and added it to the list of NRC- approved cask designs in Sec. 72.214 as Certificate of Compliance No. 1031.

IV. Plain Writing

The Plain Writing Act of 2010 (Pub. L. 111-274) requires Federal agencies to write documents in a clear, concise, and well-organized manner. The NRC has written this document to be consistent with the Plain Writing Act as well as the Presidential Memorandum, ``Plain Language in Government Writing,'' published June 10, 1998 (63 FR 31885). The NRC requests comment on this proposed rule with respect to clarity and effectiveness of the language used.

V. Regulatory Planning and Review

Executive Order (E.O.) 12866 Executive Order (E.O.) 12866, as amended by E.O. 14215, provides that the Office of Information and Regulatory Affairs (OIRA) will determine whether a regulatory action is significant as defined by E.O. 12866 and will review significant regulatory actions. OIRA determined that this proposed rule is not a significant regulatory action under E.O. 12866. Review Under E.O.s 14154, 14192, 14215, and 14300 NRC has examined this proposed rule and has determined that it is consistent with the policies and directives outlined in E.O. 14154, ``Unleashing American Energy,'' E.O. 14192, ``Unleashing Prosperity Through Deregulation,'' E.O. 14215 ``Ensuring Accountability for All Agencies,'' and E.O. 14300, ``Ordering the Reform of the Nuclear Regulatory Commission.'' This proposed rule is not considered an E.O. 14192 deregulatory action.

VI. Availability of Documents

The documents identified in the following table are available to interested persons as indicated. ------------------------------------------------------------------------ ADAMS accession No./ web link/ Document Federal Register citation ------------------------------------------------------------------------ Documents Related to Initial Certificate (Amendment No. 0), Revision 4 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 0 ML26098A208 Revision 4. Proposed CoC 1031 Amendment No. 0 ML26098A209 Revision 4 Technical Specifications (TS) Appendix A. Proposed CoC 1031 Amendment No. 0 ML26098A210 Revision 4 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 1, Revision 4 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 1 ML26098A211 Revision 4. Proposed CoC 1031 Amendment No. 1 ML26098A212 Revision 4 TS Appendix A. [[Page 39902]] Proposed CoC 1031 Amendment No. 1 ML26098A213 Revision 4 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 2, Revision 4 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 2 ML26098A214 Revision 4. Proposed CoC 1031 Amendment No. 2 ML26098A215 Revision 4 TS Appendix A. Proposed CoC 1031 Amendment No. 2 ML26098A216 Revision 4 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 3, Revision 4 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 3 ML26098A217 Revision 4. Proposed CoC 1031 Amendment No. 3 ML26098A218 Revision 4 TS Appendix A. Proposed CoC 1031 Amendment No. 3 ML26098A219 Revision 4 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 4, Revision 3 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 4 ML26098A220 Revision 3. Proposed CoC 1031 Amendment No. 4 ML26098A221 Revision 3 TS Appendix A. Proposed CoC 1031 Amendment No. 4 ML26098A222 Revision 3 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 5, Revision 3 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 5 ML26098A223 Revision 3. Proposed CoC 1031 Amendment No. 5 ML26098A225 Revision 3 TS Appendix A. Proposed CoC 1031 Amendment No. 5 ML26098A227 Revision 3 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 6, Revision 3 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 6 ML26098A228 Revision 3. Proposed CoC 1031 Amendment No. 6 ML26098A229 Revision 3 TS Appendix A. Proposed CoC 1031 Amendment No. 6 ML26098A230 Revision 3 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 7, Revision 3 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 7 ML26098A231 Revision 3. Proposed CoC 1031 Amendment No. 7 ML26098A232 Revision 3 TS Appendix A. Proposed CoC 1031 Amendment No. 7 ML26098A233 Revision 3 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 8, Revision 3 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 8 ML26098A234 Revision 3. Proposed CoC 1031 Amendment No. 8 ML26098A235 Revision 3 TS Appendix A. Proposed CoC 1031 Amendment No. 8 ML26098A236 Revision 3 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 9, Revision 3 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 9 ML26098A237 Revision 3. Proposed CoC 1031 Amendment No. 9 ML26098A238 Revision 3 TS Appendix A. Proposed CoC 1031 Amendment No. 9 ML26098A239 Revision 3 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 10, Revision 2 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 10 ML26098A240 Revision 2. Proposed CoC 1031 Amendment No. 10 ML26098A241 Revision 2, TS Appendix A. Proposed CoC 1031 Amendment No. 10 ML26098A242 Revision 2, TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 11, Revision 2 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 11 ML26098A243 Revision 2. Proposed CoC 1031 Amendment No. 11 ML26098A244 Revision 2 TS Appendix A. Proposed CoC 1031 Amendment No. 11 ML26098A245 Revision 2 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 12, Revision 2 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 12 ML26098A246 Revision 2. Proposed CoC 1031 Amendment No. 12 ML26098A247 Revision 2 TS Appendix A. Proposed CoC 1031 Amendment No. 12 ML26098A248 Revision 2 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 13, Revision 2 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 13 ML26098A249 Revision 2. [[Page 39903]] Proposed CoC 1031 Amendment No. 13 ML26098A250 Revision 2 TS Appendix A. Proposed CoC 1031 Amendment No. 13 ML26098A251 Revision 2 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 14, Revision 1 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 14 ML26098A252 Revision 1. Proposed CoC 1031 Amendment No. 14 ML26098A253 Revision 1 TS Appendix A. Proposed CoC 1031 Amendment No. 14 ML26098A254 Revision 1 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 15, Revision 1 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 15 ML26098A255 Revision 1. Proposed CoC 1031 Amendment No. 15 ML26098A256 Revision 1 TS Appendix A. Proposed CoC 1031 Amendment No. 15 ML26098A257 Revision 1 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 16, Revision 0 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 16, ML25217A298 Revision 0. Proposed CoC 1031 Amendment No. 16 ML25217A300 Revision 0 TS Appendix A. Proposed CoC 1031 Amendment No. 16 ML25217A302 Revision 0 TS Appendix B. Preliminary Safety Evaluation Report for ML25217A304 CoC 1031 Amendment 16 Revision 0. Initial Submission of an Amendment ML25080A349 Request for the NAC International MAGNASTOR[supreg] Cask System Amendment No. 16, March 21, 2025. Supplement to NAC International's ML25108A159 Request to Amendment MAGNASTOR[supreg] Cask System, Amendment No. 16, April 18, 2025. ------------------------------------------------------------------------ Documents Related to Amendment No. 16, Revision 1 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 16 ML26098A258 Revision 1. Proposed CoC 1031 Amendment No. 16 ML26098A259 Revision 1 TS Appendix A. Proposed CoC 1031 Amendment No. 16 ML26098A260 Revision 1 TS Appendix B. ------------------------------------------------------------------------ Documents Related to Amendment No. 17, Revision 0 and Revisions to Amendment Nos. 0 through 16 ------------------------------------------------------------------------ Proposed CoC 1031 Amendment No. 17...... ML26098A262 Proposed CoC 1031 Amendment No. 17 TS ML26098A263 Appendix A. Proposed CoC 1031 Amendment No. 17 TS ML26098A264 Appendix B. Preliminary Safety Evaluation Report, ML26098A207 CoC No. 1031, Amendment 17 and Revisions to Amendments 0-16. NAC International--Initial Submission of ML25211A197 an Amendment Request for the NAC International MAGNASTOR[supreg] Cask System Amendment No. 17, July 30, 2025. Submission of a Supplement to Amendment ML26064A039 Request No. 17 for the NAC International MAGNASTOR[supreg] Cask System, March 4, 2026. Submission of a Supplement to Amendment ML26075E865 Request No. 17 for the NAC International MAGNASTOR[supreg] Cask System, March 13, 2026. ------------------------------------------------------------------------ Other Documents ------------------------------------------------------------------------ User Need Memorandum for Amendment No. ML25217A296 16. User Need Memorandum for Amendment No. ML26098A206 17 and Revisions to Amendment Nos. 0 through 16. Final Rule, ``List of Approved Spent 73 FR 70587 Fuel Storage Casks: MAGNASTOR[supreg] Addition,'' published November 21, 2008. Revision to Policy Statement, 82 FR 48535 ``Agreement State Program Policy Statement; Correction,'' published October 18, 2017. Presidential Memorandum, ``Plain 63 FR 31885 Language in Government Writing,'' published June 10, 1998. ------------------------------------------------------------------------ The NRC may post materials related to this document, including public comments, on the Federal rulemaking website at https:// www.regulations.gov under Docket ID NRC-2026-2047. In addition, the Federal rulemaking website allows members of the public to receive alerts when changes or additions occur in a docket folder. To subscribe: (1) navigate to the docket folder (NRC-2026-2047); (2) click the ``Subscribe'' link; and (3) enter an email address and click on the ``Subscribe'' link. Dated: June 17, 2026. For the Nuclear Regulatory Commission. Michael King, Executive Director of Operations. [FR Doc. 2026-13261 Filed 6-30-26; 8:45 am] BILLING CODE 7590-01-P

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