Document: NRC Regulatory Guide
Document ID: 151ab883-1221-4a79-88d6-a2631cce2239
Document Type: regulatory_guide
Title: Decommissioning of Nuclear Power Reactors (Rev. 1)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2134/ML21347A080.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.184
CFR Part: 
CFR Title: 

Content:
ions of the facility and site that contain radioactive contaminants are promptly removed or decontaminated to a level that permits termination of the license shortly after cessation of operations. The Decommissioning GEIS found DECON to be an acceptable decommissioning method. DG-1347 Revision 1, Page 7 (2) SAFSTOR. The facility is placed in a safe, stable condition and maintained in that state (safe storage) until it is subsequently decontaminated and dismantled to levels that permit license termination. During SAFSTOR, a facility is left intact; however, the fuel has been removed from the reactor vessel, and radioactive liquids have been drained from systems and components and then processed. Radioactive decay occurs during the SAFSTOR period, thus reducing the quantity of contaminated and radioactive material that must be disposed of during decontamination and dismantlement. The definition of SAFSTOR also includes the decontamination and dismantlement of the facility at the end of the storage period. The Decommissioning GEIS found SAFSTOR to be an acceptable decommissioning method. (3) ENTOMB. Radioactive systems, structures, and components are encased in a structurally long-lived substance such as concrete. The entombed structure is appropriately maintained and kept under continued surveillance until the radioactivity decays to a level that permits termination of the license. Because most power reactors will have radionuclides in concentrations that exceed the limits for unrestricted use even after 100 years, this option will generally not be feasible. However, this option might be acceptable for reactor facilities that can demonstrate that radionuclide levels will decay to unrestricted use levels in about 100 years. Entombment is to only be considered as a last resort for decommissioning. The expectation is that licensees would select this method only under unique decommissioning circumstances. Entombment would be used only if this option provides more benefit