Environmental impact monitoring of a goldmine

The Rosia Montana Goldmine,  located in the so-called “Golden Quadrilateral” in the Apuseni  Mountains, Western Romania, has been an active gold mine since Roman times. Currently the mine is inactive but previous mining activities have left deep environmental scars. Recent plans to reopen the mine have sparked intense protests amongst national and international organisations.  If realized, Rosia Montana would become Europe’s largest open pit gold mine, and this would have a devastating  impact on the local environment. 

As part of the EU-FP7 IMPACTMIN study subsidized by the European Commission, this area was surveyed using a combination of remote sensing data (Satellite imagery, UAV technology, airborne hyperspectral  imagery, gammaray data) and a variety of field data, including a detailed spectral study of soil, rocks and vegetation.  

The combined remote sensing data were used to characterize:

  • The open pit area: mineralogy, geochemistry, geomorphology
  • The tailings dam area: Mineralogy, geochemistry, tailings dispersal into einvironment
  • The acid drainage from the mine and the tailings dam.
  • The acid generating/buffering potential of various geologic formations in the area.
  • Condition of soils, farmland and forest areas: soil mineralogy and vegetation stress.  

Middle right: Acid mine drainage with pH<1, running off into the local surface water system.
 

Mapping of Acid drainage related secondary iron minerals by:

Top left: Smartplanes natural color image
Top right: Worldview 2 satellite image, resolution 50 cm

Bottom left: Hyperspectral images from manned aircraft, resolution 50 cm 
Bottom right: Drone aerial photograph, resolution 5 cm