LEBANON — Fire investigators are waiting for extreme heat to abate at the site of a former plywood mill, where at least one building was destroyed in a blaze this morning. They will begin working at the site Tuesday morning, said Lebanon Fire Prevention Specialist Jon Davis.

This morning, a plume of black smoke filled the sky and was visible from several miles away.

Students at Riverview Elementary School in Lebanon were evacuated to Seven Oak Middle School for the day due to the amount of smoke in the air, said a representative from the school district office.

The Lebanon Fire District responded to the site near Santiam Highway and Market Street at 6:57 a.m. and discovered one building on fire.

The flames were threatening another building, Davis said, and firefighters instantly upgraded the call from a first alarm to a third alarm.

Additional firefighters from around the area then arrived to assist.

From the highway this morning, two trucks could be seen with firefighters in raised buckets spraying water down into the fire.

No injuries were reported.

By late ths morning, officials had not yet determined the cause of the fire or the extent of the damage.

The main mill building remained standing after the fire was out.

Eric Buckner, a nearby resident, said he observed a narrow column of smoke a little before 7 a.m. on the northeast corner of the property, close to River Road, and called in an alarm.

Within a couple of minutes the fire had grown exponentially, he said.

Buckner said massive explosions shook his family at their home about 400 yards away.

“We thought we could smell chlorine in the air as the smoke traveled over our house and that’s when we decided to leave,” he said.

The mill site is owned by a company called Lebanon Hardboard LLC, although it hasn’t been used for lumber production for several years.

Managing partner Rece Bly announced his intention to turn the mill into a wood waste steam-power plant shortly after the site was purchased in January 2006, but the plans never materialized.

In September of that year, firefighters extinguished a blaze that reportedly gutted the mill building. That fire was said to have been started by work crews cutting metal on the third floor near a pile of sawdust.

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