What are bad impacts oil sands can cause on the environment?

Northern Alberta's oil sands are increasingly becoming a source of political conflict, both domestically and globally, as scrutiny of the world's second-largest known oil reserve intensifies. While recent production in the oil sands has driven rapid economic growth in Alberta, there is increasing concern that this growth is causing unprecedented ecological harm. Major environmental non-government organizations (ENGOs), such as Greenpeace and the Pembina Institute, and local First Nations have begun to call for a moratorium on new oil sands projects until associated environmental destruction can be mitigated. At the same time, prominent political observers, such as former Alberta PremierPeter Lougheed, have argued publicly that development in the oil sands is proceeding at a rate that is not economically and socially beneficial for Alberta. As the primary regulatory body responsible for the oil sands, the Alberta government is responsible for shaping most of the economic, social and environmental policies that guide oil sands development. Numerous complex and divisive policy problems that all demand resolution compete for the government's attention. The provincial government, however, has remained generally hostile to any calls for a slowdown in oil sands growth.