Portfolio: Energy + Waste: Tar sands oil, a sour crude, is highly enriched in sulfur, requiring a large amount of energy to ref

Crude oils are designated "sweet" or "sour," depending on how much of the impurity sulfur, which must be removed, they contain. Tar sands oil, a sour crude, is highly enriched in sulfur, requiring a large amount of energy to refine. At Syncrude Mildred Lake, sulfur is removed from the crude oil and stored in the massive pyramids seen here. These two plots cover together occupy more than 1.8 million square feet of land.