“We are not out of the woods, but the fire is behaving as we would like for it to behave,” Winston-Salem Fire Chief Trey Mayo said in a briefing Tuesday afternoon.
The fire forced emergency responders to urge the evacuation of about 6,000 people earlier, including Wake Forest University students and more than 200 inmates from a nearby prison.
“If that doesn’t convey the gravity of this situation and how serious folks need to take it, I don’t know how else to verbalize that,” Mayo said.
Through aerial surveillance, officials have been able to determine that there is no imminent heat threat to the rail car on the back of the facility that contains about 100 tons of ammonium nitrate, according to Mayo.
Officials on Tuesday were able to shut off two lines that were flowing natural gas into the vicinity of the fertilizer plant, the fire chief said.
As the winds begin to shift into the evening, Mayo warned residents that they will be able to see a haze in the air, and they will begin to smell an odor similar to “spent fireworks.”
The odor is from irritants and not considered toxic, he said.
Still, people with “sensitive respiratory systems” should avoid being outside, Mayo said.
“We do not encourage folks to be out exercising, running and walking and doing that sort of thing,” he said.
Residents urged to evacuate
At one point, fire trucks were driving down every road in the evacuation zone — and going door-to-door in some places — using a public address system to urge residents to evacuate, Winston-Salem Fire Department Battalion Chief Patrick Grubbs said early Tuesday.
The blaze began Monday night at the plant. After battling it for two hours, the fire department pulled back its crews after the blaze spread to a rail car containing ammonium nitrate, Grubbs said.
“Right now, the fire is still active, and there’s still potential for explosion. We’re asking all the citizens to evacuate the area for a 1-mile radius around it,” he said Tuesday morning. “We do not know the full extent of the time we’ll be here. It will not be anytime soon that we’ll be leaving.”
The one-mile radius around the plant was still in place Tuesday afternoon.
The cause of the fire remains under investigation, Grubbs said, and the fire department has been in touch with the company that owns the plant. The Winston Weaver Co. did not respond immediately to CNN’s request for information.
“We will continue working with first responders and relevant officials to ensure safety of the community, and we would participate fully in the investigation into the cause of the fire,” he said.
Mayor Pro Tempore Denise Adams heard sirens around 7 p.m., Monday, then a “tremendous boom,” while watching TV, she said.
The fertilizer plant had passed a routine inspection in December, officials said.
Inmates moved and students advised to say indoors
Authorities overnight moved about 220 inmates from Forsyth Correctional Center to the minimum-security Alexander Correctional Institution in Taylorsville, about a 90-minute drive west of Winston-Salem, said North Carolina Department of Public Safety spokesperson John Bull.
There was no imminent threat to the Forsyth facility, Bull said. Emergency officials recommended moving the prisoners as a precaution. They’ll be returned to Forsyth when it’s safe, he said.
“Travel in the evacuation area around 4400 North Cherry Street will become increasingly difficult as police begin to shut down roads and prohibit vehicle traffic. Faculty, staff and students are encouraged to evacuate as soon as possible. Use personal vehicles and carpool when possible. Parking anywhere on campus is allowed,” Wake Forest said early Tuesday.
At least 90 firefighters and up to about 150 emergency personnel — including police and others — have been working on the fire and evacuating the area, Grubbs said.
CNN’s Ray Sanchez, Tina Burnside, Eliott C. McLaughlin contributed to this report.