Reprocessing facilities
regularly release radionuclides such
as krypton-85, argon-41, tritium, and
carbon-14, into the atmosphere, and
others, such as tritium, strontium-90,
cesium-137, and plutonium-241, to
surface waters. France and the UK
have reduced the volume of released
effluents since the 1990s.
The bulk of the volume of wastes associated
with nuclear power originates
from mining and processing the uranium
ore for fabrication into fuel. The
largest and most problematic wastes
associated with mining are uranium
mill tailings, which are the rock residue
from the extraction of uranium from the
ore. The problem is that all the uranium
daughter products, in particular radium
(Ra-226) and its daughter radon (Rn-
222), from millions to billions of years
of decay, remain with the residual rock.
These pose risks from windblown dust
exposure, radon emissions, and leaching
into groundwater. Currently there
are over 900 million cubic meters of
tailings covering almost 5800 hectares
at uranium mines and mills around the
globe.44 The mill tailings are generally
kept in large sludge ponds on site. Like
coal mine impoundments, these structures
can fail, with catastrophic results
to surrounding communities and the
environment.