The Goo Earth

"[W]hat angers environmentalists and an increasingly vocal segment of Albertans [is that] the oil sands projects have grown in number and size so suddenly that there hasn't been time to consider the long-term environmental costs. Groups like the Pembina Institute, an Alberta-based environmental think tank, have proposed a moratorium on new projects until technology can catch up. Greenpeace, which opened an Edmonton office last summer, is campaigning for a complete halt to all development.

There's no getting around it: Oil produced from the bitumen lying in the sand under Alberta's boreal forest is one of the dirtiest fuels in the world. Under current conditions, extracting one barrel of synthetic crude from a mine requires roughly two to four barrels of fresh water from the nearby Athabasca River (an amount top water scientists say the river cannot sustain), along with 750 cubic feet of non-renewable natural gas and about four tonnes of tarry sand and "overburden" – the industry term for what Mr. Groot calls soil.

Steaming it out of the ground – a process that will dominate most of the future expansion since the vast majority of bitumen is found too deep to be mined – creates a crisscross of pipes across the wilderness and requires large amounts of energy to boil the necessary water. The impact of so-called "in situ" extraction on groundwater supply and quality, environmentalists say, is uncertain.

What's more, the oil sands are easily cast as a climate-change villain: In 2006, researchers at Simon Fraser University found that the mining and upgrading of oil sands bitumen created five times as many greenhouse-gas emissions as would come from producing oil from a conventional well.

The most dramatic visible legacy of mining the oil sands – and an example environmentalists cite of the uncertainty of the long-term impact – are the large, manufactured lakes that store the cloudy waste water left over from the extraction process. Many scientists now believe the tailings-pond clay will take 500 to 1,000 years to settle on its own.

Barring new technology, and if production increases, as predicted, to four million barrels a day by 2020, it will be virtually impossible for Canada to meet its international climate-change commitments."