National Public Radio: DAVID GREENE, HOST: Crude oil from Canada's tar sands is providing a booming business for American refineries, but residents of one Chicago neighborhood complain that a byproduct of that business has become a health hazard. They want towering mounds of a dusty substance known as petroleum coke, or petcoke, moved out of the city. And as NPR's Cheryl Corley reports, Chicago is now requiring one company storing the substance to do just that. CHERYL CORLEY, BYLINE: Residents on Chicago's far southeast...