The Catalyst Mill in Rumford accidentally discharged 15,600 gallons of cooling water contaminated with paper fiber into the Androscoggin River on Thursday afternoon, a mill spokesman said.

The Maine Department of Environmental Protection said “thermal seal water,” which is used in the paper-making process, leaked into the river.

“The department investigated the occurrence and spoke with mill representatives who tested the wastewater and confirmed it was essentially hot water with paper fiber,” DEP spokesman David Madorem said. “Based on current information, this incident did not require a response from DEP to be onsite; however, we are in contact with the Catalyst paper mill and will continue to monitor the situation.”

The DEP statement did not say whether there was any threat to the river, although mill spokesman Tony Lyons said it posed no threat to wildlife or the public.

There were early reports of up to 57,000 gallons of contaminated water being dumped in the river. When the system malfunctioned at about 2:30 p.m., the mill was required to notify local fire departments and the state, which happened before mill operators completely understood the extent of the discharge.

The mill is allowed to discharge water that has not had contact with paper manufacturing, but is used for cooling, he said. The sewers that collect that cooling water have a turbidity meter that determines whether there are paper fibers in the water. That meter malfunctioned, so instead of diverting the water to a holding tank because of the paper fiber, it instead released it into the river, he said.

“Paper fiber was the only material in the water. It was not a chemical spill,” Lyons said. He said the water had no contact with chemicals used in the papermaking process.

“We contacted the DEP and the commissioner’s office. … They consider it a non-emergency event.” It is, however, a violation of the mill’s discharge permit with the DEP.

The mill will probably have to clean up the paper fiber that settled in a retention pond at the discharge site, from which point it passes over some rocks and into the river, he said. It was unclear whether the mill would be fined.

The Catalyst Mill makes coated paper used in magazines and food and beverage packaging. The mill employs 800 people, according to its website.

David Hench can be contacted at 791-6327 or at:

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