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
CFR Part: 
CFR Title: 

Content:
52, and 100 that are subject to the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.). These information collections were approved by the Office of Management and Budget (OMB), control numbers 3150-0014, 3150-0011, 3150-0151, and 3150-0093. Public Protection Notification The NRC may neither conduct nor sponsor, and a person is not required to respond to, an information collection request or requirement unless the requesting document displays a currently valid OMB control number. DG-4025, Page 5 B. DISCUSSION Reason for Issuance Discharges of liquid effluents through surface waters are normally monitored and reported as described in RG 1.21; however, discharges through ground water pathways have not been a routinely monitored pathway. This RG provides guidance on how to determine liquid effluent discharges through the ground water pathway. Background As plants began to undergo decommissioning in the late 1990s to early 2000s, instances of subsurface and/or ground water contamination were identified. Several operating facilities also identified ground water contamination resulting from spills and leaks or equipment failure. In one instance, low levels of licensed material were detected in a private well located on property adjacent to a nuclear power plant. The source of these releases included a wide range of structures, systems and components important to safety (SSCs), such as condensate storage tanks, spent fuel pools, vacuum breaker valves along circulating blowdown lines, and buried pipe leaks. The principal radionuclide released was hydrogen-3 (tritium). Other radionuclides released include strontium-90, cesium-137, nickel-63, cobalt- 60, and antimony-125, depending upon the source. Although the releases were not a significant public health issue, they needed to be addressed. In March 2006, the NRC formed the Liquid Radioactive Release Lessons Learned Task Force (LLTF) to evaluate the liquid radioactive releases and to make recommendations. The task