For nearly four months, the Aliso Canyon methane leak just north of Los Angeles spewed several thousand metric tons of potent greenhouse gases into the air before it was finally sealed in February. The disaster displaced residents, forced schools to close, and incited widespread distrust in the local government's regulation of the oil and gas industry.

Few people realize that Los Angeles was actually built on oil. The Aliso Canyon natural gas facility is just one of thousands of oil and gas drilling and storage sites located in and around the city, which is also home to the country's largest urban oil field. Thousands of wells dot the cityscape, and many operate in highly populated, low-income neighborhoods.

VICE News visited Los Angeles to investigate how carcinogenic fumes from urban oil drilling are affecting local communities.

Read "Record LA Gas Leak Could Bring Summer Blackouts to Southern California"

Read "LA's Methane Leak Was the Biggest in US History"