Minerals and Resources rules for exchange listing are pretty tight with respect filing third party independant reports that assess mineral volumes and estimates, economic feasibility, environmental impact, and human rights etc.
While it's possible that some things are covered up in these relatively modern capital projects (eg: like conditions mining copper in PNG in days of yore leaving substantial impacts today) it's unlikely due to modern communications and the known fact that everything gets out and doesn't remain hidden - more so today than back when PNG was literally and figuratively obscured by clouds.
Austrlia is keeping clean, and you can knock yourself out looking into
and report anything you find to the TSX.