Document: NRC Regulatory Guide
Document ID: 29acb072-d497-44e6-ac1c-a053c0a468a0
Document Type: regulatory_guide
Title: Meteorological Monitoring Programs for Nuclear Power Plants + HISTORY - HISTORY DG-1164 , Third Proposed Revision 1, published 10/2006 Draft ES 926-4 , Second Proposed Revision 1, entitled "Meteorological Measurement Program for Nuclear Power Plants," published 04/1986 Draft SS 926-4 , First Proposed Revision 1, entitled "Meteorological Programs In Support of Nuclear Power Plants," published 09/1980 Revision 0, entitled "Onsite Meteorological Programs," was issued as Safety Guide 23
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0625/ML062540408.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.23
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CFR Title: 

Content:
the impact of plant operation on the environment, joint frequency distribution types of data summaries should be compiled, which will permit the description of the frequency and extent of fogging and icing conditions caused by plant operation. 7. Special Considerations for Complex Terrain Sites The plant’s preoperational meteorological monitoring program should provide an adequate basis for atmospheric transport and diffusion estimates for the exclusion area distance, the outer boundary of the low-population zone, and the hypothetical maximally exposed member of the public (e.g., the site boundary and the nearest resident, vegetable garden, and milk and meat animals within 8 kilometers (5 miles) in each downwind sector). At some sites, because of complex flow patterns in nonuniform terrain, additional wind and temperature instrumentation and more comprehensive programs may be necessary. For example, the representation of circulation for a hill-valley complex or a site near a large body of water may need additional measuring points to determine airflow patterns and spatial variations of atmospheric stability. Occasionally the unique diffusion characteristics of a particular site may also warrant the use of special meteorological instrumentation and/or studies. The plant’s operational meteorological monitoring program should provide an adequate basis for atmospheric transport and diffusion estimates within the plume exposure emergency planning zone [i.e., within approximately 16 kilometers (10 miles)].11 DG-1164, Page 12 8. Special Considerations to Support Emergency Preparedness In order to identify rapidly changing meteorological conditions for use in performing emergency response dose consequence assessments, 15-minute average values should be compiled for real-time display in the appropriate emergency response facilities (e.g., control room, technical support center, and emergency operations facility). The 15-minute averaged values should be calculated using