ALLENTOWN, Pa. — A shelter-in-place order was lifted about 6:30 p.m. Friday in the area near a Lehigh County Authority water treatment facility that experienced a hazardous vapor incident.
A chemical mix-up caused a hazmat situation inside the building, and five employees were sent to the hospital Friday morning as a precaution, officials said.
After the vapor inside the facility along Martin Luther King Jr. Drive had stabilized, hazmat crews ventilated the building throughout the day. The facility was reopened Friday night about 8:30 p.m.
Contractors for LCA are doing remediation inside, officials said Friday night.
The previous shelter-in-place order was in effect out of an abundance of caution and covered the area within roughly a half-mile of the water treatment facility. It impacted about 1,300 residents.
Additionally, homeless people living in the area were asked to evacuate Friday morning for their safety, officials said.
Though the shelter-in-place order has since lifted, part of Martin Luther King Jr. Drive — from South 10th Street to South 15th Street — remains closed, officials said Friday evening.
Chemical delivery apparently went into the wrong tank
The incident began after a routine delivery of chemicals that are used in the water-treatment process.
LCA Director of Communications Taylor Stakes said sodium hypochlorite was apparently delivered into the wrong tank, where it mixed with polyaluminum chloride.
“So hypochlorite and polyaluminum chloride aren’t really good to mix together, and unfortunately, we had a delivery of hypochlorite that apparently went in the wrong tank,” Stakes said.
The apparent chemical mix-up created a hazardous vapor inside the facility and triggered a large emergency response Friday morning.
The building was evacuated as firefighters and hazmat crews worked to determine the extent of the release and to manage the vapor.
Changing winds expand precautions
As crews monitored the air around the facility, shifting winds became a concern.
Allentown Fire Department Capt. Jon Hammel said emergency crews needed to account for where the vapor could travel if it escaped the building.
By Friday afternoon, shifting winds prompted officials to expand the precautionary shelter-in-place area around the treatment facility. The shelter-in-place order has since been lifted.
Drinking water not affected
Despite the emergency at the treatment facility, LCA officials stressed that the area’s drinking water remained safe and the public water supply had not been affected.
LCA CEO Liesel Gross said the authority has several sources available to keep water flowing even if treatment operations at the facility are temporarily disrupted.
“We have a very diverse supply of water,” Gross said.
“At the moment, we are feeding water from one of our springs that can continue to feed through the plant and through the distribution system as it is right now,” she said at a news conference Friday afternoon.
“And we also have a couple of days’ worth of water in storage,” she added.
Gross said the authority has time to determine what happened inside the building without threatening the area’s water supply.
Investigation continues
Officials were still working Friday evening to determine exactly how the chemicals were mixed.
Officials had not announced when the roadway would return to normal operations.
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