Document: NUREG-0800
Document ID: 37e64905-5f3c-4221-9ce6-b3089b164d6f
Document Type: srp
Title: LONG-TERM DIFFUSION ESTIMATES
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070237.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.3.5
CFR Part: 
CFR Title: 

Content:
ensees should, in addition to complying with the limits set forth in 10 CFR Part 20, make every reasonable effort to maintain radiation exposures, and releases of radioactive materials in effluents to unrestricted areas, as far below the limits specified in 10 CFR Part 20 as is reasonably achievable. The Commission encourages licensees to operate their facilities in a way that maintains occupational doses and those resulting from the release of radioactive effluents ALARA. 10 CFR Part 50, Appendix I, provides numerical guidance for doses to meet the ALARA criterion. Meeting the guidance provided in Appendix I to 10 CFR Part 50 provides assurance that the health and safety of facility workers and the public will be protected.17 DRAFT Rev. 3 - April 1996 2.3.5-4 III. REVIEW PROCEDURES The reviewer verifies that appropriate atmospheric dispersion models, with adequate onsite meteorological data as input to the models, have been used to calculate relative concentration and relative deposition at appropriate distances and directions from postulated release points during routine airborne releases of radioactive gases. 18 1. Atmospheric Dispersion Models The applicant's models are compared to the general modeling criteria presented in Regulatory Guide 1.111. The models should be suitable to topography of the site and vicinity, plant configuration, and release characteristics. Additional information for determining model suitability may be found in standard references such as "Meteorology and Atomic Energy - 1968." The staff performs an independent evaluation of long-term dispersion characteristics. Identification of release points and release characteristics is provided by ETSB. RAB provides the locations of receptors of interest.Release points, release characteristics, and locations of receptors of interest are identified. Each release should be characterized as 19 continuous or intermittent. Using the criteria presented in Regulatory Guide 1.111, each release is