New information shows nearly 4 million Californians are at risk if trains carrying oil through the state should have an accident.  

The revelations come to light as the Bay-Area based Valero Refining Company unveils its plans to run crude-oil trains through Roseville and Sacramento.

A series of rail route maps, released today by the Natural Resources Defense Council, shows more than 250,000 Sacramento residents and more than 175 schools lie within one mile of the evacuation zone.

And, while a report commissioned by the city of Benicia says the likelihood of a crash or spill is low, NRDC's Dianne Bailey believes too many people are in harm's way.

"Some of the concerns stem from the conditions of the track -- poor maintenance and such," Bailey said. 

The council's senior scientist also points to issues with the trains.

"A lot of the biggest safety concerns come with the tank cars themselves being quite old and not being built for carrying these types of hazardous materials," she said. 

If Valero Refining's plans are approved, oil shipments would begin moving through the area by early next year.