Document: NUREG-0800
Document ID: a397b98f-e122-4d15-8471-5259fb45b58b
Document Type: srp
Title: and BTP 11-6 since the use of durable and passive design features would provide
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1305/ML13051A458.pdf
Revision Date: 2023-06
Chapter: 11
Section ID: 11.2
CFR Part: 
CFR Title: 

Content:
effluent concentration limits, as was the case in previous guidance. The reason for this change is the need to better account for the effects of multiple exposure pathways. Releases may affect surface water and groundwater differently; consequently, the impact in some instances may be by way of direct consumption of water, while in others the impact may be only by indirect use of water (e.g., for livestock watering or crop irrigation). These different exposure scenarios and pathways can be quantified, because the applicant is expected to describe uses of water resources based on local or regional land-use census information. As described in the 2007 version of BTP 11-6, the acceptance criteria stated that the postulated release should not result in radionuclide concentrations in useable surface water or groundwater exceeding the effluent concentration limits (ECLs) of 10 CFR Part 20, “Standards for Protection against Radiation,” Appendix B, “Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs) of Radionuclides for Occupational Exposure; Effluent Concentrations; Concentrations for Release to Sewerage,” Table 2, Column 2, and Note 4 for radionuclide mixtures. While the ECLs are a reasonable standard for direct consumption of water, their use is not as obvious or practical for indirect uses of water or for the consumption of impacted food products. As a result, the revision of this BTP applies a dose-based limit instead, because it provides the most flexibility in assessing and meeting the acceptance criteria, regardless of the postulated exposure scenarios. The dose acceptance criteria are as follows: A. Radioactive releases associated with the postulated failure of a tank and components should not do the following: i. result in radioactive material concentrations leading to a dose in excess of 100 mrem (1 mSv ) at the point of entry into the nearest existing or a known future water supply when (1) used as a source of water for direct human