"No leaks, no spills, no impact on climate change. The Keystone XL pipeline would have 'no impact' on the environment if it were approved and built, Republican presidential candidate Donald Trump said on Tuesday. For that reason, the billionaire said he would approve the controversial project 'immediately' if elected president. ...

Though there’s been fierce debate over how large the proposed pipeline’s environmental impact would be, it’s rare to hear someone say Keystone XL would have no environmental impact at all. Even the U.S. State Department said that, while there would not be a major impact on climate change, the pipeline would likely experience spills in the course of its lifetime.

The risk of an oil spill from Keystone XL is particularly concerning to environmentalists because of the type of oil involved. Tar sands oil is more difficult to clean up than conventional crude because, when it spills into water, it does not float. Instead, it gradually sinks, making normal cleanup techniques and equipment of little use. This is partially what made the 2010 Enbridge oil spill so difficult to clean up."

Emily Atkin reports for Climate Progress August 20, 2015. [2]