Document: NRC Regulatory Guide
Document ID: d812c779-c17b-4eb3-9d66-b532cd68bd03
Document Type: regulatory_guide
Title: Decommissioning Planning During Operations + HISTORY - HISTORY 12/2011 – DG-4014 , Proposed New Guide
Source: NRC Regulatory Guide Division 4
Source URL: https://www.nrc.gov/docs/ML1115/ML111590642.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-4.22
CFR Part: 
CFR Title: 

Content:
nsive site characterization. The required surveys should include, but are not limited to, the following: a. building interiors, including in and around joints, drains, hoods, exhaust stacks, and other features that could provide pathways for residual radioactivity to concentrate or migrate to inaccessible areas, b. the soil and other media in outside areas at the facility, c. subsurface media, especially around building footers, subsurface pipes and conduits, and below-grade tanks, and d. ground water. The DPR does not alter the existing requirement to conduct surveys reasonable under the circumstances to evaluate the magnitude and extent of residual radioactivity. It does explicitly state in 10 CFR 20.1501(a) that the subsurface must be included in these surveys. The intent of the rule is to ensure that licensees identify the extent of significant residual radioactivity on site; therefore, licensees should survey in places where such residual radioactivity is more likely to exist. Licensees should also evaluate the potential for significant residual radioactivity to migrate and to concentrate such that it would not meet the release for unrestricted use criteria of § 20.1402. That is, if the existing significant residual radioactivity will naturally reduce to levels that meet unrestricted release criteria by the time of license termination, the DPR does not require any further action. For NRC licensees who have subsurface residual radioactivity with no current or projected groundwater contamination, a minimal, routine monitoring plan may remain in effect through license termination activities. The DPR also places a lower bound on the amount of residual radioactivity that licensees should record: that which would require remediation at the time of license termination to meet the unrestricted release criteria of 10 CFR 20.1402. However, records of surveys performed that demonstrate that the residual radioactivity has not exceeded the level of significant residual