Winsome actor and activist Mark Ruffalo does just about the best job possible explaining the proposed tar-sands pipeline and how you can help fight it in Washington, D.C., starting Aug. 20. Watch his quick video primer below. (Do it if only to watch a scruffily tousled Mark speak from the heart. Sigh … )

Got a dial-up connection? Hate watching ruggedly handsome Sundance-darlings-cum-Earth-advocates? No matter. Here are four disturbing reasons why you should fight the tar sands:

  1. The proposed Keystone XL pipeline runs from Alberta, Canada to Texas.TransCanada’s 1,700-mile-long Keystone XL pipeline will stretch across the continent, from Alberta to Texas and into the Gulf of Mexico. If approved, it will be among the largest industrial projects in the world.
  2. You know it’s bad when it makes conventional oil look good: The process to make liquid fuel from the tar sands generates two to four times the amount of greenhouse gases per barrel as conventional oil, earning the tar sands the nickname “carbon bomb.”
  3. Extracting crude bitumen (the semisolid fossil fuel found in tar sands) pollutes the air and water of nearby boreal forests and wetlands that serve as natural carbon sinks. These same forests and wetlands also serve as breeding grounds and habitat for 30 percent of North America’s land birds (about 215 species) and are home to fragile populations of wolverines, caribou, lynx, and grizzly bears.
  4. As Ruffalo notes, “This pipeline will travel over some of the richest farmland and most beautiful, pristine wilderness on the continent — and spills are inevitable.” Tar-sands oil gets pumped under high pressure, and high concentrations of chloride salts, sulfur, abrasive minerals, and acids act as corrosives.
 

President Obama will decide as soon as September on whether to OK the Keystone XL pipeline, so fast action is critical. Tim DeChristopher’s Peaceful Uprising will coordinate sustained protests and camping in front of the White House from Aug. 20-Sep. 3. Over 2,000 people have committed to participating in nonviolent, civil disobedience during these two weeks. Bill McKibben, James Hansen, Danny Glover, and many others are expected to attend to put “our values into action.”

“The action could turn out to be the largest ongoing collective civil disobedience in the history of our movement,” says Flora Bernard, co-director of Peaceful Uprising.