SUPPLEMENTARY INFORMATION:

I. Background

The NRC is issuing this ISG to supplement guidance provided in NUREG-1757, Volume 2, Revision 2, “Consolidated Decommissioning Guidance, Characterization, Survey, and Determination of Radiological Criteria,” which was issued in July 2022 (ADAMS Accession No. ML22194A859). The ISG provides additional guidance developed after Revision 2 to NUREG-1757, Volume 2, was published related to surveys of open surfaces in the subsurface, including open excavations, materials planned for reuse, and substructures. The ISG also provides guidance on the use of commonly used decommissioning dose modeling codes to develop clean-up levels for submerged and partially submerged substructures, and on methods to evaluate risk from existing groundwater contamination. NRC staff held two subsurface investigations workshops on July 14-15, 2021, and May 11, 2022, to help support the development of this ISG, and contracted with Oak Ridge Associated Universities to develop guidance on acceptable survey methods.

On October 19, 2023, the NRC issued a Federal Register notice (88 FR 72112) soliciting public comment on its draft ISG, “Radiological Survey and Dose Modeling of the Subsurface to Support License Termination.” The NRC received comments from the Nuclear Energy Institute, by letter dated December 13, 2023 (ADAMS Accession No. ML24009A037); Energy Solutions, by letter dated December 18, 2023 (ADAMS Accession No. ML23353A243); and the State of New Jersey Department of Environmental Protection, by email dated December 21, 2023 (ADAMS Accession No. ML24009A080). No other comments were submitted. The NRC staff considered those comments in developing the final version of the ISG. The staff's responses to the comments are provided in Appendix D, “Comment Responses,” of the final ISG. The NRC also issued a draft Regulatory Analysis for the draft ISG for public comment (ADAMS Accession No. ML23177A009). No comments were received on the draft Regulatory Analysis. The final Regulatory Analysis is available in ADAMS under ML24200A233.

II. Backfitting, Forward Fitting, and Issue Finality

Issuance of this ISG will not (i) constitute backfitting as defined in sections 50.109, 70.76, or 72.62 of title 10 of the Code of Federal Regulations (10 CFR), “Backfitting,” and as described in Management Directive (MD) 8.4, “Management of Backfitting, Forward Fitting, Issue Finality, and Information Requests”; (ii) affect issue finality of any approval issued under 10 CFR part 52, “Licenses, Certifications, and Approvals for Nuclear Power Plants”; or (iii) constitute forward fitting as that term is defined and described in MD 8.4. This ISG states the NRC staff's position on acceptable methods for surveys of open surfaces in the subsurface, including open excavations, materials planned for reuse, and substructures, as well as guidance on the use of commonly used decommissioning dose modeling codes for submerged and partially submerged substructures to develop clean-up levels, and on methods to evaluate risk from existing groundwater contamination. Applicants and licensees will not be required to comply with the positions set forth in this ISG.

III. Congressional Review Act

This ISG is a rule as defined in the Congressional Review Act (5 U.S.C. 801-808). However, the Office of Management and Budget has not found it to be a major rule as defined in the Congressional Review Act.

89 FR 79317