Truck leak snarls traffic on Outbound Edens Expressway between Morton Grove, Skokie

Truck leaking corrosive substance snarls traffic on Outbound Edens Expressway between Morton Grove, Skokie

Traffic on the outbound Edens Expressway between Morton Gove and Skokie is stalled due to a truck leaking a corrosive material blocking a lane at Dempster.

CBS Skywatch was over the scene as the situation first developed around 6:30 am. The tractor trailer's tank was labeled as containing a corrosive material.

Illinois State Police said the truck is leaking sodium bisulfate. Sodium bisulfate is an acidic salt often used to lower pH in swimming pools, spas and industrial water systems, and is also used in metal finishing, food processing, cleaning products and sanitizing. It is typically a dry, white crystalline substance.

The truck pulled over in the right lane just past the westbound entrance to the Edens at Dempster, with the lane blocked off for the emergency response.

The leak appeared to be at the very back of the truck, off the rear. Fire and hazmat teams were there by 6:45 a.m., dumping sand under the back of the truck to soak up the liquid and make sure the leak remained contained in a strategy known as "dike, dam, divert" – basically, taking steps to ensure that none of the hazardous material was able to spread.

The Demspter entrance to northbound I-94 is closed, as is the right lane, amid the ongoing hazmat response. As a result, traffic between Morton Grove and Skokie has slowed to a crawl, and on the inbound side there has also been a slowdown due to rubbernecking.

ISP did not have any further information or an estimate for when the Dempster ramp would reopen.

Drivers should avoid that stretch of the Edens, or allow extra travel time if they have no choice.