Environmental chemistry of technetium

Safe disposal of waste is perceived by public opinion as probably the greatest technical problem of the nuclear industry. This concern derives from the large quantities of radioactivity involved and from the suspicion that man-made barriers are not completely reliable for the lifetime of such waste. Therefore, the biogeochemical cycling of long-lived radionuclides resulting from nuclear power generation represents an important factor influencing decisions regarding the future development of the nuclear industry. As far as technetium is concerned, it should be mentioned that the hazard from the isotope /sup 99/Tc remains practically unchanged for some 30,000 years because of its 2.1x10/sup 5/ year half-life. In this paper the information available on the environmental chemistry of technetium is discussed in order to evaluate the importance of chemical processes in determining the distribution of technetium in the biosphere