Document: NRC Regulatory Guide
Document ID: 42f2dcf0-38ba-4f75-84d4-e60f4bbf9162
Document Type: regulatory_guide
Title: Assessment of Abnormal Radionuclide Discharges in Ground Water to the Unrestricted Area at Nuclear Power Plant Sites Appendix-Simple Ground Water Model for Estimating Offsite Tritium Activity Flux + HISTORY - HISTORY 12/2015 – DG-4025-Proposed New Guide
Source: NRC Regulatory Guide Division 4
Source URL: https://www.nrc.gov/docs/ML1523/ML15237A388.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-4.25
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CFR Title: 

Content:
try Initiative to Control Degradation of Underground Piping and Tanks,” Ref. 24). Harmonization with International Standards The International Atomic Energy Agency (IAEA) has established a series of safety guides and standards constituting a high level of safety for protecting people and the environment. IAEA safety guides present international good practices and increasingly reflects best practices to help users striving to achieve high levels of safety. Pertinent to this regulatory guide IAEA-TECDOC-482, “Prevention and Mitigation of Groundwater Contamination from Radioactive Releases” (Ref. 25), discusses the characteristics of the releases (primarily for two scenarios, namely an underground storage tank, and a severe reactor core accident); modeling of radionuclide movement in the subsurface; prevention and mitigation techniques; monitoring and sampling; and quality assurance and quality control. The document also includes an appendix of suggested ground water models developed in the early 1980s for both unsaturated and saturated flow conditions. A related IAEA safety standard, WS-G-3.1, “Remediation Process for Areas Affected by Past Activities and Accidents” (Ref.26), briefly describes site characterization, setting remediation criteria, and establishing remediation planning and implementation. This RG is consistent with the basic safety principles provided by these two IAEA guides. Documents Discussed in Staff Regulatory Guidance This RG endorses the use of one or more codes or standards developed by external organizations, and other third party guidance documents. These codes, standards and third party guidance documents may contain references to other codes, standards or third party guidance documents (“secondary references”). If a secondary reference has itself been incorporated by reference into NRC regulations as a requirement, then licensees and applicants must comply with that standard as set forth in the regulation. If the secondary