Document: NUREG-0800
Document ID: 7bbfa5be-36ba-4273-8f24-038130581ae5
Document Type: srp
Title: SHORT-TERM DISPERSION ESTIMATES FOR ACCIDENTAL ATMOSPHERIC RELEASES
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340583.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.3.4
CFR Part: 
CFR Title: 

Content:
ta as input to the models, have been used to calculate relative concentrations at appropriate distances and directions from postulated release points during accidental airborne releases of potentially hazardous materials. If adequate onsite meteorological data are not available for the construction permit review, the reviewer must assure that adequate conservatism has been applied to the calculated relative concentrations for accidental airborne effluent releases based on available data. The reviewer's evaluation must support the following type of concluding statement, to be used in the staff's safety evaluation report: The staff concludes that atmospheric dispersion estimates are acceptable and meet the relevant requirements of General'Design Criterion 19 and 10 CFR Part 100. This conclusion is based on the conservative assess- ments of postaccident atmospheric dispersion conditions that have been made by the applicant and the staff from the applicant's meteorological data and appropriate diffusion models. These atmospheric dispersion estimates are appropriate for the assessment of consequences from (1) radioactive releases for design basis accidents in accordance with 10 CFR Part 100, §100.11 and (2) onsite and offsite releases of hazardous materials in accordance with General Design Criterion 19. In the determination of the atmospheric dispersion estimates, the applicant has followed the guidelines of Regulatory Guides 1.5, 1.23, 1.24, 1.25, 1.77, 1.78, 1.95 and 1.145 (as appropriate). 2.3.4-5 Rev. 1 - July 1981 The input to the safety evaluation report will also include a brief summary of the relative concentrations (X/Q) calculated by the staff, reference to dispersion models used, and a comparison between the values computed by the staff and the applicant. V. IMPLEMENTATION The following is intended to provide guidance to applicants and licensees regarding the NRC staff's plans for using this SRP section. Except in those cases in which the applicant proposes