The Courdraies district in Gif-sur-Yvette: the radon roaring years

This document first recalls the history of the site of the SNR (Societe nouvelle du radium) which, between 1904 and 1957, hosted industrial activities of radium extraction and a research laboratory. It was at that time the first industrial installation in the world to produce this natural radio-element. The pitchblende ore was coming from Cornwall, transported by train to the small Gif railway station, bulk unloaded, and carried with a barrow along a path named 'the radium path'. The author recalls the debates about this installation, notices that, during the first years, radioactivity was not taken into account, and reports the evolution of the activities until they were stopped and the installations remained abandoned. The district was converted into a housing one and partial de-pollution actions were performed due to the presence of radon. The author reports what happened to the different installations, describes the present situation of the district, indicates the previous locations of installations, and shows that some radioactivity has been present during the years, and is still present (maps and measurements are provided). The issue of a total decontamination is addressed and discussed.