Lithium ion battery likely sparked Arlington Heights garbage truck blast, officials say

Arlington Heights Fire Department officials believe the Dec. 6 garbage truck fire and explosion that injured three first responders and strew debris blocks away was caused by a lithium ion battery collected during recycling pickup.

Fire Chief Lance Harris also pointed to mechanical failures on the Groot truck, which was unable to dump its load or activate any of 10 pressure relief devices that would have emptied the vehicle’s five compressed natural gas fuel containers and likely prevented the massive blast.

The relief devices — located at the top and bottom of each fuel cylinder placed atop the truck — are supposed to activate between 212 and 220 degrees.

“We showed up and had flames shooting out the top of this truck,” Harris said. “You don’t have to know anything about fire behavior to know that it was 212 degrees.”

“It’s very important that these (devices) go off and they release the pressure so the pressure can’t build and we wouldn’t have an explosion,” he added.

The fire chief presented the department’s internal review of the explosion to the mayor and village trustees at a village board meeting Tuesday night. Officials initially said representatives from Groot — Arlington Heights’ waste hauler — would attend the public presentation, but withdrew due to pending litigation.

The explosion occurred just before 4 p.m. Dec. 6 on the 500 block of Derbyshire Avenue, just south of Euclid Avenue.

Minutes before the blast, the first responding fire department officer asked the truck’s driver to dump the recyclables that had been collected, which would have allowed firefighters to extinguish the blaze on the street and taken the compressed natural gas cylinders atop the truck out of the equation, Harris said.

It’s a best practice that’s been employed in three of the six garbage truck fires that have occurred in Arlington Heights since 2017, he said.

But the truck wouldn’t release the load, likely because a hydraulic line melted or safety sensors wouldn’t allow it to operate, according to the chief.

The system had been working properly four hours earlier, when the driver dumped the morning haul at a waste transfer station, he said.

Village officials have asked residents not to dispose of batteries in recycling bins or the regular trash, but to bring them to village hall for proper disposal. Recycling also is available at Best Buy, Home Depot, or by doing a search at call2recycle.org.

The highly flammable lithium ion batteries can explode or ignite when damaged or pressure is placed on them, as occurred Dec. 6 in the garbage truck’s compactor. During previous fires, it’s been customary for Groot drivers to compress the load to try to squeeze out oxygen and tamp down flames.

But Harris said Groot will no longer try to compact the contents.

“If they have a fire in one of these trucks in Arlington Heights today or tomorrow, the first thing they’re doing is getting off the main thoroughfare, looking for a side street or a parking lot, and they’re dumping the load,” Harris said. “Once the load is off the truck and there’s no fire in the truck, the (natural gas) doesn’t come into play any longer.”

New fire department protocols call for firefighters to keep a 300-foot distance from a garbage truck fire, while a police department drone is deployed to make sure the gas is venting. First responders will evacuate residents within that radius, and put out an online public service announcement.

If the fire is smoldering, crews will try to put it out, but otherwise will just let it burn, Harris said.

Arlington Heights firefighters did a training session on compressed natural gas vehicle fires exactly a year ago, learning to listen for a loud hissing noise if the relief valves are working properly. Of the 165 vehicles in Groot’s fleet based in Elk Grove Village, 115 run on compressed natural gas.

The explosion on Dec. 6 occurred 11 minutes after the truck driver called 911, and just four minutes after firefighters got to the scene.

Harris and other command staff were standing about 100 yards away when the cylinders violently ruptured, sending truck parts and other debris several blocks away, pealing off siding and roofs from nearby homes, shattering windows, and deploying car air bags.

Two police officers and one firefighter were injured, but not seriously.

Harris called it a “miracle.”

“I’m here to tell you I’m blessed to be standing here tonight,” he said.