A fire on the roof caused the sprinkler system to mix with a water-reactive chemical at the plant, Rockdale County fire Chief Marian McDaniel said during a press conference late Sunday. She previously said that a sprinkler head malfunctioned. It’s unclear what started the fire, which was placed under control around 4 p.m. The roof and walls of the plant have since collapsed.

A shelter-in-place order was issued for all of Rockdale County until midnight. Officials said residents will likely see the plume of smoke — now a chemical reaction and not a fire — for several days. About 17,000 people live in Conyers, located roughly 25 miles east of Atlanta.

On Sunday morning, McDaniel said crews had been working on taking the material away from the water source at the facility and that the fire was contained to the roof. But the fire reignited around noon as crews were removing the material. There were employees inside the plant but no injuries have been reported at this time.

“Now we are just trying to mitigate the debris so we can offload the product,” the chief said.

Standing in front of the large plume of smoke that turned orange at one point, Rockdale sheriff Eric Levett on Sunday afternoon “strongly asked” residents to stay away from the area, which included I-20 in both directions between Salem Road and Turner Hill Road. That stretch of the interstate and all of its exits in Rockdale County are closed, the Newton County Sheriff’s Office said.

Officials created an evacuation zone for a large portion of Conyers due to the fire.

“The interstate as you can see is backed up. We are working with the Georgia State Patrol and Georgia Department of Public Safety to assist with traffic control,” the sheriff said.

There was more traffic than usual in Conyers on Sunday as drivers tried to navigate the closed roads and section of the interstate. A Kroger store on Hwy 138 was shuttered, while a QuikTrip on Klondike Road was pay at the pump only. The lights from police cruisers were visible throughout the area, many of which came from neighboring jurisdictions.

Over her seven years with the fire department, McDaniel said it was the third such incident of “this magnitude,” at the plant. The Georgia Emergency Management and Homeland Security Agency (GEMA) said it issued a shelter in place order on behalf of Rockdale’s emergency management agency, but no timetable has been provided as to when the area will be safe.

In September 2020, a “TCCA reaction and decomposition” caused another plume of hazardous chemicals to be released into the air at the Conyers plant, exposing facility personnel and nine firefighters to “dangerous fumes,” according to a U.S. Chemical Safety and Hazard Investigation Board report. Surrounding businesses were evacuated and a section of I-20 was closed for about six hours. The report stated another decomposition involving TCCA happened four days later at the plant, but no one was injured.

“TCCA is used throughout the country in pool care and, when put in large bodies of water such as a pool, breaks down slowly, releasing chlorine in the water,” the report added. “However, when TCCA comes into contact with small amounts of water and does not dissolve, it can undergo a chemical reaction that generates heat, causing the decomposition of TCCA, which produces toxic chlorine gas.”

While it’s unclear what chemical was involved with the fire on Sunday, officials said the Environmental Protection Agency (EPA) will be sampling the plume to determine its contents. Before the severity of the chemical is determined, evacuation sites are being held at Lucious Sanders Recreation Center, 2484 Bruce Street in Lithonia, Bert Adams Boy Scout Camp at 218 Scout Road in Covington, and Wolverine Gym at 8134 Geiger Street in Newton County. A previous site was listed at 90 Hardin Street in Conyers, but it is now in the evacuation zone, officials said.

A dispatcher with the Rockdale fire department confirmed that Rockdale Piedmont Hospital was evacuating some of its patients.

On Monday, all Newton County Schools will be closed out of an abundance of caution, officials said. The Rockdale County District Attorney’s Office said its offices and the county courthouse would also not be open Monday due to the fire.

“We ask for your prayers for the safety of the residents of Rockdale and the first responders committed to protecting our community,” the DA’s office said.

As of Sunday morning, there was not a plan in place for residents unable to return to their homes by the evening. County officials will let the public know on its social media channels when the EPA determines the threat level to the community. A shift in the plume and report from the EPA will likely influence how long the area would be impacted.

“We have about 60 folks over at the scene working through this, so it’s going to be a long process,” McDaniel said.

According to its website, BioLab “is the swimming pool and spa water care division of KIK Consumer Product.” That company is based in Lawrenceville.

The site goes on to say that their brands are “industry leaders” that “pioneered computerized water testing and the 3-step system for pool and spa care.”

“We are actively responding to an occurrence at our facility in Conyers, Georgia,” a BioLab representative said in a statement. “Our employees are accounted for with no injuries reported. Our team is on the scene, working with first responders and local authorities to assess and contain the situation. As always, the safety of our community remains our top priority.”

The fire led to the cancellation of church services from Rockbridge to the Northside County line. Officials said local hospitals will be putting out a PSA about steps to take for those affected by the incident.

The road closures include:

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