Open AccessCarbon-14 in waste packages for spent fuel in a tuff repository
Author(s) -
R.A. Van Konynenburg,
C. F. Smith,
H. W. Culham,
Harry D. Smith
Publication year - 1986
Language(s) - English
Resource type - Reports
DOI - 10.2172/59998
Subject(s) - spent nuclear fuel , radioactive waste , environmental science , carbon fibers , waste management , atmosphere (unit) , radiochemistry , chemistry , nuclear engineering , materials science , physics , engineering , meteorology , composite number , composite material
Carbon-14 is produced naturally by cosmic ray neutrons in the upper atmosphere. It is also produced in nuclear reactors, in amounts much smaller than the global inventory. About one-third of this is released directly to the atmosphere, and the other two-thirds remains in the spent fuel. Both the Environmental Protection Agency and the Nuclear Regulatory Commission have established limits on release of the {sup 14}C in spent fuel. This is of particular concern for the proposed repository in tuff, because of the unsaturated conditions and the consequent possibility of gaseous transport of {sup 14}C as CO{sub 2}. Existing measurements and calculations of the {sup 14}C inventory in spent fuel are reviewed. The physical distribution and chemical forms of the {sup 14}C are discussed. Available data on the release of {sup 14}C from spent fuel in aqueous solutions and in gaseous environments of air, nitrogen, and helium are reviewed. Projected {sup 14}C behavior in a tuff repository is described. It is concluded that {sup 14}C release measurements from spent fuel into moist air at temperatures both above and below the in situ boiling point of water as well as detailed transport calculations for the tuff geological environment will be needed to determine whether the 10CFR60 and 40CFR191 requirements can be met. 56 refs., 1 tab