AUBURN — Paper manufacturer Cascades Auburn Fiber will try a new method to cut down on the smelly wastewater between its Lewiston Road plant and the Twin Cities sewage treatment plant.

John Storer, superintendent of the Auburn Sewer District, said neighbors and people living between the Cascades plant and the river regularly complain of a rotten egg smell around manholes. The smell can be traced back to wastewater from the plant that contains sulfides. Those can break down into smelly hydrogen sulfide gas.

“But we have something new we’re going to try,” Storer said. “We’re almost ready to go, but we don’t know the exact date. Then we’re going to install monitors in manholes at various spots to see the concentration of various odors. We’ll do a human sniff test, but we’re going to have independent machines to verify those results, too.”

Vivian Matkivich, pre-treatment coordinator for the Lewiston-Auburn Water Pollution Control Authority, said the company has been adding chemicals to make the wastewater more alkaline. That keeps the sulfide from producing the smelly gas until it reaches the control authority plant on Lincoln Street in Lewiston.

“It is effective but not 100 percent effective,” she said. “But you can’t always control what other people put in the sewer, and things can break down the reaction.”

The process can break down in hot weather or when other sewer customers flush something acidic into the system, she said.

Matkivich said the new plan is to pre-treat Cascade’s wastewater with hydrogen peroxide to break down the sulfide and to keep the gas from forming.

“They’re going to try to remove the sulfides completely with the hydrogen peroxide treatment,” she said. “It also acts like a disinfectant.”

Storer said the company plans to begin testing the new process late in July or early in August. He said the sewer district would send out notices to residents later this week.

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