Recent and less recent industrial activities have generated radium-bearing waste. It is only slightly radioactive but there are much larger quantities of it than the other types of waste. As its name suggests, this waste contains traces of radium and its descendants from the decay chain of uranium, traces of which are found in the Earth's crust. Alongside uranium, which is long-lived (it has a half-life of 1600 years), there is also radon, a natural radioactive gas with a half-life of four days.
Some radium-bearing waste comes from the cleanup of former radium industry sites, which were contaminated when this industry was flourishing before 1940. Other more recent waste comes from the processing of weakly radioactive ores such as monazite, which contains rare earths and their oxides in varying proportions. About fifteen chemical elements with similar structures and properties are known as the rare earths or lanthanides.
Until July 1994, Rhône-Poulenc and then Rhodia Electronics and Catalysis processed monazite to extract the rare earths, at their factory in La Rochelle. Since August 1994 this factory has imported pre-processed ores with lower levels of radioactivity. The rare earths are used in electronics, magnetism (tape heads), the automotive industry (catalytic converters), television screens, etc.
The radioactivity level of radium-bearing waste is usually somewhere between a few dozen Bq and a few thousand Bq per gram. The radioelements are mainly long lived alpha-emitters.
Radium-bearing waste is classed as low-level long-lived waste (LLW-LL). It has its own special conditioning and disposal process, on which research is being done by ANDRA.
Access to page in french.