Facilities that store petcoke in the state within a mile of neighborhoods and other "vulnerable populations" will have to fully enclose the oil refining byproduct under new legislation Illinois Attorney General Lisa Madigan proposed Wednesday.

Under the proposed legislation, petcoke and other refinery material also have to be completely covered at facilities within a mile of schools, hospitals and nursing homes. Mounds of petcoke, which can pollute the air and water, are being stored at facilities on Chicago's Southeast Side.

State Rep. Barbara Flynn Currie (D-Chicago) and Madigan's office crafted the proposed bill. 

If passed, the legislation will require that petcoke and coal be fully enclosed when moving to and from storage facilities on trucks, barges and other modes of transportation. The material would have to be loaded and unloaded in enclosed quarters.

Announcement of the proposed measure comes a week after Chicago Mayor Rahm Emanuel said he will introduce an ordinance next month designed to ban new petcoke facilities from setting up shop in the city and prevent existing sites from expanding.