Solano County Fire battled a 3-alarm fire at the Alco Metal and Iron Company at 321 Azuar Drive on Mare Island in Vallejo Friday afternoon.
The North Bay fire triggered a shelter-in-place order for people within breathing distance of it, as a column of thick, black smoke was billowing from the metal recycling facility and was blowing over North Vallejo.
At first, fire crews said they did know what was burning, and they worried the smoke was toxic. But the order has now been lifted.
"The challenge is we don’t know what’s in the pile. We're worried about it being toxic," Vallejo fire spokesman Mike Brooks said.
As of Friday night, fire crews were still pulling the pile of debris apart and putting water on it.
The column of smoke has environmentalists concerned. Hours after a fire started at the metal yard, crews continued to pour water on a smoldering pile.
"About an acre in size, 50 feet tall whatever could be inside," Brooks said. "It’s washers. It's dryers. It’s water heaters."
The Solano County hazmat team took air and water samples. When results came back normal around 8 p.m., crews lifted the shelter in place advisory.
Deb Self from San Francisco Baykeeper said investigators may never know what kind of toxins the column of smoke carried into the air. But with metals and plastics burning, Self said it is likely pollutants ended up in the bay and nearby estuaries, putting wildlife in danger.
"A lot of toxic pollutants can build up and cause reproductive harms…for fish and for birds that eat the fish," Self said.
In a statement, Alco said it is grateful no one was hurt.
Crews did keep the fire contained to the yard. No structures were damaged.
Crews said they will stay all night, and the cause of the fire is under investigation.