Old gold mine subsidence

The vicinity of the closed Hollinger gold mine near Timmins, Ontario has experienced extensive subsidence problems in recent years. AMEC found that Coherent Target Monitoring (CTM) based on radar satellite images could serve as a very useful prediction tool in owner Placer Dome’s subsidence-monitoring programme. AMEC’s study of satellite data between 1992 and 2003 found subsidence in the range of 25 millimeters to 55 millimeters in some areas where it previously was thought to be stable.