This past Tuesday, we spoke to filmmaker Josh Fox and the environment activist Dallas Goldtooth about the protests at Standing Rock, North Dakota. For our Bonus Weekend Podcast, we’ve decided to look back at some other segments about the front lines of environmental protection and political activism. In 2013, we spoke to Mark Weiss about his documentary “A Fierce Green Fire,” and one of the film’s subject, Lois Gibbs, who led the protests at Love Canal, started the Center for Health, Environment & Justice. In 2014, who spoke to Frances Beinecke, former head of the Natural Resources Defense Council. And last year, to bring it close to home, we spoke to Joseph Alexiou who wrote a history of one of the most important waterways in the history of New York harbor that has since been turned into an industrial dumping ground: the Gowanus Canal.