BEAVER COUNTY(KDKA) — Potential hazards remain at the site of a Beaver County fire that led to a cloud of chlorine gas being released.

Progress on the site is proving to be expensive for the Pennsylvania Departmentment of Environmental Protection.

Workers were at the former Pool Doctor-Beaver Alkali Products site in Rochester early Thursday morning, wearing white jumpsuits and face masks.

Some workers wore construction hats.

(Photo Credit: KDKA)

As recently as Tuesday, contractors with the DEP removed, neutralized and disposed of most of the chemicals and debris from the building that ignited.

The building was demolished to completely remove the chemicals stored inside.

The footprint of the building has been filled in, and that site is now secure.

“Even though our response had taken place earlier this summer, there was a chemical reaction that occurred on the property on July 12 and 13,” said Lauren Fraley of the DEP.

In July, the site caught fire, creating a cloud of chlorine that settled over the river.

Investigators believe the building’s collapsing roof caused a mixing of chemicals that erupted in flames.

A public meeting was held Wednesday night to address concerns, provide updates and gather information.

As for the next phase of the cleanup with the larger building that houses the bowling alley, that’s still unclear when it will begin.

“We had a structural engineer go through the building, let us know what we can and can’t do from a safety standpoint, and then we will slowly begin to categorize those chemicals that are inside and then remove and properly dispose of them,” said Fraley.

The DEP said it could cost more than $1 million to clean up the hazardous chemicals inside.

The building also has a collapsed roof, and public access to the site remains restricted while work continues.

The DEP is waiting on a structural survey before beginning work on the larger building. They say it could take months to clean up the chemicals that still remain inside.