Vezza Mine, a former gold mine includes a three-compartment shaft with four underground levels down to a depth of 741 metres, This mine was never put in production since its construction around 1997. In 2010, North American Palladium bought the mine and had to dewater the underground infrastructure to restart mine exploitation. Mine water was highly charged with Total Suspended Solids (TSS), Iron (Fe), Zinc (Zn) and Copper (Cu) and it was not possible to discharge that water into the natural environment. First step was to pump and treat water to dewater mine galleries and second step was to treat mine water on a regular basis. ASDR installed a chemical conditioning unit coupled with a Geotube® bag filtration unit. Treated water reached and exceeds the regulatory discharge criteria of the Quebec Government Directive 019. System has been running since January 2011 and still produces the same water quality.