Companies like Starbucks and McDonald’s have been trying for 30 years to recycle those single-use polyethylene-coated paper cups, the kind that coffee comes in. It turns out the impossible just takes longer.

Georgia-Pacific says it’s invested about $45 million to equip paper mills in Green Bay, Wisconsin, and Muskogee, Oklahoma to turn the cups from landfill waste into recycled toilet tissue, napkins and paper towels.

“The testing is done … We have validated we can do it,” says John Mulcahy, vice president of sustainability for the Atlanta-based Georgia-Pacific.

About three months ago, the company worked with municipalities in the areas surrounding their Green Bay and Muskogee mills to let residents know they can put out the plastic-coated cups as part of blue-bin curbside recycling.

“We started with homes because we believed that it is cleaner and lot of the studies show that it is cleaner (than restaurants),” Mulcahy explained, speaking of the condition of items put into recycling bins.

Studies also show that about 75% of single-use cups that leave restaurants end up in the trash bin at home. Now those cups can go into home recycling bins instead.

“It’s both the biggest opportunity and the easier of the two streams to deal with,” he says.

The goal is make cup recycling available at local Starbucks and McDonald’s locations (along with all the other places that sell the ubiquitous liquid holders) some time down the road. Hundreds of billions of the cups are used annually in the United States and around the world, with very little recycling.

Georgia-Pacific isn’t ready to say how soon that may be, but Mulcahy says other recycling companies also are working to turn the cups into reusable fiber.

“I think what you’ll like see happening sooner is different companies will announce they are accepting cups in the stream,” targeting residential areas like Georgia-Pacific’s mills in Wisconsin and Oklahoma, Mulcahy says.

Georgia-Pacific is working with the NextGen Consortium, a global initiative led by Closed Loop Partners with founding partners Starbucks and McDonald’s, to help open opportunities for paper cup recycling. The Coca-Cola Company, Yum! Brands, Nestlé and Wendy’s are supporting partners. The World Wildlife Fund (WWF) is an advisory partner.

The Food Service Packaging Institute, the trade association for the foodservice packaging industry in North America, also is involved. The cup recycling effort in Green Bay and Muskogee is the culmination of about two years of effort.

What’s the secret that’s kept these cups out of the recycling stream for so long?

Polyethylene (PE) coatings, along with any remaining liquid and food left behind from use, have historically left single-use paper cups out of the recovery and recycling process, according to a news release. Georgia-Pacific has found a way to effectively recapture cup fiber from PE-coated cups while screening out the coatings.

“It’s existing technology,” Mulcahy says of how his company arrived at the solution. “We’ve kind of worked to adjust our processes so we can deal with it.”

“It’s water and agitation,” Mulcahy adds, likening the process to a clothes washer.

“In the past, the cups were going to go in the reject stream. But now the plastic that is removed goes in the reject stream but the paper fiber goes out with the water.”

Company officials declined to discuss the volume of PE-coated cups they’re taking in at the Green Bay and Muskogee mills.

But they noted the recycled fibers from the cups are being used to make recycled products that are used in the same places where the formerly “impossible to recycle” cups came from, including restaurants and office buildings.