In a Notoriously Polluted Area of the Country, Massive New Chemical Plants Are Still Moving inThe industrial stretch of the Mississippi River between Baton Rouge and New Orleans, a region known as “Cancer Alley,” is one of the most highly polluted areas in the country. A ProPublica analysis using a scientific model developed by the Environmental Protection Agency shows that some of the neighborhoods where new plants are being built already have very high concentrations of toxic chemicals. But Louisiana continues to approve the building of these new plants and the expansion of existing ones.