LEETSDALE (KDKA) – A massive, five-alarm fire sent a large black plume of smoke over parts Allegheny and Beaver counties Tuesday as it tore through an industrial park in Leetsdale and took hundreds of firefighters several hours to get under control.

According to Allegheny County Emergency Services, the fire broke out at the Lubrizol Corporation’s Oilfield Chemistry site in the 100-block of Leetsdale Industrial Drive.

The company is involved in the development of oil and gas production.

A worker called 911 around 10:15 a.m. to report an explosion and fire.

The fire spread to a second building nearby. Firefighters took up a defensive position and watered down six other buildings.

Officials say that the two chemicals involved – ammonium persulfate and sodium chlorite – are inhalation contact hazards.

The Allegheny County Health Department Director Dr. Karen Hacker issued this statement:

“The Allegheny County hazmat teams, which are fully-equipped emergency response teams, were on-scene. PA DEP assessed air quality. These chemicals can have an impact if inhaled in high doses. Any individuals who are experiencing trouble breathing or intense coughing, especially those with an existing chronic condition, should seek medical attention. However, at this point in time, we at the Allegheny County Health Department, do not believe there is any immediate risk to the public. Our monitors have not shown any levels of concern and are not expected to. Winds should continue to remain fairly brisk out of the southerly directions even overnight, so we do not anticipate Allegheny County will receive much impact or elevated readings.”

An evacuation order was issued for all homes on Washington Road in Leetsdale. About 75 homes were involved in the evacuation. Those residents were taken to the Quaker Valley High School gymnasium. The order was finally lifted just before 4 p.m.

Rudy Plese was able to return to his home late Tuesday.

Plese was working in Bridgeville when he heard about the smoky chemical fire.

Even though his neighborhood was under an evacuation order, he drove back home and parked his car on another street so he could “sneak” home to check on his three dogs. Plese said they were all okay.

Hazmat was called to the scene and officials went door-to-door to make sure everyone had gotten out. Nearby Buncher and Leetsdale Business Parks were also evacuated as a precaution.

Some other residents were ordered to shelter in place.

“We have made some progress with releasing the shelter in place orders that have been out there and also with the school districts that were sheltering in place. We had some concern if they were going to be able to release the students on time; happy to say that is taking place,” said Allegheny County Emergency Services Chief Alvin Henderson.

Henderson said more than 200 firefighters from about 20 companies battled the flames.

Eight people, including three firefighters and five workers, were treated at area hospitals and released, or were treated at the scene.

Two workers suffered chest pains and were taken to Allegheny General Hospital. A third worker suffered chemical burns and was taken to UPMC Mercy Hospital.

None of those injuries are believed to be life-threatening.

Two firefighters suffered minor injuries, but refused medical treatment at the scene. Additionally, another firefighter was treated for chest pains.

Thick black smoke could be seen from parts of Beaver County and was even picked up on radar.

Ambridge, Aliquippa and Hopewell elementary schools were advised to keep students inside due to the smoke.

Hopewell High School officials canceled all extracurricular activities after school Tuesday. They also did not send any students to the ROTC program.

“It was coming our way, coming across, and that was our area of concern – Ambridge, Hopewell, Aliquippa school districts were right in the path,” said Wesley Hill, the director of Beaver County 911.

Beaver County 911 also did a downstream notification to everyone to the Ohio line. They were told to monitor water intakes, but so far there are no reports of illness.

The Quaker Valley School District’s administrative office is right in the industrial park.

“We received word there was an apparent fire and the staff evacuated right away,” said Superintendent Heidi Ondek.

Officials were asking motorists to avoid Route 65 in the Leetsdale area into the afternoon hours.

Because of all the hot spots that still needed dousing late into Tuesday, officials say the fire marshal will begin investigating the cause of the fire Wednesday morning.

There’s been no damage estimate made by the Lubtrizol Oilfield Solutions company that owns the chemical warehouse.

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