Calgary, Alberta-based TransCanada said on Jan. 26 that it has contracted with enough companies to proceed with the 1,980-mile Keystone XL pipeline. It would be the first to transport crude oil from Canada’s oil-sands region to refineries on the U.S. Gulf Coast. The proposed $12-billion, 36-in.-dia pipeline could move up to 150,000 barrels of oil per day. Together with the existing Keystone pipeline, the two lines would move up to 250,000 bbl daily. The project, which is contingent on U.S. State Dept. approval, is opposed by several environmental and local groups. The American Petroleum Institute says the pipeline is “a
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.