A fire has been smoldering underground at the Bridgeton Landfill (labeled "Former Active Sanitary Landfill" in this image) since late 2010. There is radioactive waste in the two purple regions labeled Operable Unit 1 Area 1 and Operable Unit 1 Area 2.
Credit Environmental Protection Agency report p. 15
Updated Wednesday, May 22, 5:30 p.m.: The Department of Health & Senior Services is also posting its evaluations of the air monitoring data here. The regulatory standards that DHSS is using to estimate the health risks from landfill fumes are here.