ABSTRACT
Radioactive waste (radwaste) is produced in the extraction or subsequent use of natural or artificial radionuclides and said to be discharged when the user disposes of it without intention of using it further. All stages of the nuclear fuel cycle produce radwastes in the form of gases, liquids, sludges and solids which, because of their inherent toxity, must either be treated to remove most of the contaminants before being released to the environment or must be so diluted that contaminants are below permitted levels. However, it is at the so-called back-end of the nuclear fuel cycle – the stages following removal of used fuel from the reactors – where radwaste management comes into sharpest focus. Two basic concepts are inherent in radwaste disposal practice: the first is 'dilute and disperse to the environment', and the second is 'concentrate, contain and isolate'.
