Document: NRC Regulatory Guide
Document ID: 94d9f3d5-978d-4aea-9ba7-486ca7f8503a
Document Type: regulatory_guide
Title: Standard Format and Content of Decommissioning Cost Estimates for Nuclear Power Reactors
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0131/ML013100099.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.202
CFR Part: 
CFR Title: 

Content:
cilities” (Ref. 1), evaluated the environmental impact of these three methods. The supplemental information to the 1988 decommissioning rule (53 FR 24019) also discussed these three methods. A short summary of the three methods of decommissioning follows. DECON: The equipment, structures, and portions of the facility and site that contain radioactive contaminants are removed or decontaminated to a level that permits termination of the license shortly after cessation of operations. The Generic Environmental Impact Statement (GEIS) found DECON to be an acceptable decommissioning method. SAFSTOR: The facility is placed in a safe, stable condition and maintained in that state until it is subsequently decontaminated and dismantled to levels that permit license termination. During SAFSTOR, a facility is left intact, but 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 phase, thus reducing the levels of radioactivity in and on the material, and, potentially, the quantity of material that must be disposed of during radiological decontamination and dismantlement (D&D). The GEIS found SAFSTOR to be an acceptable decommissioning method. ENTOMB: ENTOMB involves encasing radioactive structures, systems, and components in a structurally long-lived substance, such as concrete. The entombed structure is appropriately maintained, and continued surveillance is carried out until the radioactivity decays to a level that permits termination of the license. The NRC staff has concluded that entombment can be a viable decommissioning method for many situations. However, because most power reactors will have radionuclides in concentrations exceeding the limits for unrestricted use even after 100 years and because current regulations require that 4 decommissioning be completed within 60 years of cessation of operation, the NRC is considering a rulemaking to