I'd call your attention to Corporate Social Responsibility: A Legal Analysis, by Michael Kerr, Richard Janda, and Chip Pitts, published by LexisNexis. They make the argument that if Canada passes legislation such as this, everybody will come up to Canadian standards. The reason is that the mining industry is so integrated; when an Australian company buys a Canadian company--which has happened--and has operations around the world, the argument is that they will operate at the highest standards because everything else is just too much grief. It actually brings up everybody.
On May 25th, 2009. See this statement in context.