Each week, up to 40 trains hauling crude oil move through the Chicago region, an analysis of documents by the Chicago Tribune shows. Such information was recently provided by main railroads to the Illinois Emergency Management Agency.

Each train moves at least a million gallons of crude oil, the newspaper reported.

In May, U.S. Transportation Secretary Anthony Foxx ordered railroads to provide the information to state emergency response officials following accidents involving trains carrying flammable Bakken crude oil.

"Releases of petroleum crude oil, subsequent fires and environmental damage resulting from such releases represent an imminent hazard," the transportation secretary said at that time.

The documents provided to the newspaper do not detail the specific train routes due to "trade secrets or (proprietary) commercial or financial information," according to the Illinois Emergency Management Agency. The release of such information would also reveal "vulnerability assessments, security measures and response policies" meant to safeguard neighborhoods, the agency said.

The newspaper was able to determine that the majority of the trains are moving on the BNSF Railway through Cook, DuPage, and Kane counties. Each week, as many as 30 trains carrying crude oil move in these areas on the railway.

In Cook, DuPage and Will counties, between five to seven trains carrying the liquid move on the Canadian National Railway.

The Canadian Pacific railway reported that it moves an average of four trains hauling crude oil each week through Lake, Cook and DuPage counties. And as many as two trains roll through Cook and Will counties each week on the Union Pacific railroad. 

Most fire departments in the Chicagoland area are not prepared to handle big fires or explosions that can occur due to a crude train derailment, according to the newspaper. In the event of such an incident, the majority of the fire departments in Illinois would rely on assistance from other departments through the Mutual Aid Box Alarm System. In Chicago, the fire department is prepared to send out a "foam task force" to any part of the city, the newspaper reported.

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