The Petcoke: Tracing Dirty Energy exhibit at the Museum of Contemporary Photography (MoCP) in Chicago took place from July 21st to Oct 9th, 2016 and features MoCP commissioned works by artists in response to the environmental and public health impact of petcoke, a dust-like waste product containing carbon, toxic heavy metals, and other dangerous compounds resulting from oil refining processes in the Chicago region and beyond. 
These audio interviews are part of Terry Evan's photographic and audio series "Petcoke vs. Grassroots."