Document: NUREG-0800
Document ID: db9f5ff5-cad8-4af5-848b-a22889b3fb51
Document Type: srp
Title: describes the design acceptance criteria for waste gas systems (as part of the
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0707/ML070730056.pdf
Revision Date: 2023-06
Chapter: 11
Section ID: 11.3
CFR Part: 
CFR Title: 

Content:
ive decay of oxygen and nitrogen isotopes. Particulates and radioiodines are assumed to be removed by pretreatment, gas separation, and intermediate radwaste treatment equipment. The release should be assumed to occur within the building structure housing the waste gas system storage tank or the main decay position of the system. It should further be assumed that the effluent resulting from the postulated event will be released to the environs without continuous effluent radiation monitoring to automatically isolate and/or terminate the effluent release. In addition, ground-level release without credit for a building wake factor should be assumed, and a conservative (5 percent) short-term diffusion estimate (X/Q), as determined by a method outlined in the acceptance criteria in SRP Section 2.3.4, should be assumed. No deposition is assumed to occur during downwind transport. 2. Staff Method for Analysis A. Pressurized Storage Tanks: The safety analysis for the radiological consequences of a single failure of an active component in a waste gas system with compressed gas storage (holdup or decay) tanks or cover gas tanks assumes that the tank being filled has a major leak to the environs. The following general procedural steps should be used for this analysis: i. The radioactive noble gas inventory in the tank, at 100-percent capacity, should be determined based on the maximum expected radioactive source term and the system design capacity using the parameters and principal components considered for pretreatment and collection of waste gas to the waste gas system tanks during normal operation, including anticipated operational occurrences. The assumptions and parameters used in the analysis should be described and justified to include among others: a description of the event leading to the release, release path from the affected system and building to the environment, type of release, duration of the release, basis for the noble gas source term, assumed receptor