Workers sort through recycling materials on a conveyor belt as they are sent through a complex sorting machine on Wednesday, Feb. 17, 2016 at the Hamm's Recycling Facility, 26195 Linwood Road.

Among the consequences of China’s new ban on solid waste imports could be an increase in recycling bills for Lawrence residents.

China has processed a large share of recyclable material worldwide, and towering bales of plastic, paper and other recyclables now sit unsold at some recycling plants. Though leaders at the local Hamm recycling plant said they have found buyers for recyclables previously sold to China, the ban has affected the overall market.

“There has been a slight depression in pricing for certain commodities,” said Hamm director Charlie Sedlock. “And as I understand it, some recycling firms that generate low-quality material are having hard time shipping those either around the United States or to China.”

The City of Lawrence contracts with Hamm for its single-stream residential service and is charged per ton of material. While the effects of the ban are still unfolding, if low prices for material cause recycling processing fees to increase, it could have direct effects on how much recycling service costs Lawrence residents.

China notified the World Trade Organization last summer that it would stop importing a list of 24 materials beginning this year, including some plastics and mixed paper. The ban has already caused buildups at recycling plants in the United Kingdom, Canada and the United States, according to various news reports.

China cited the contamination in recyclable materials as the reason for the ban, stating that it would no longer be accepting “foreign garbage.” For those recyclable materials not banned, the Chinese government has said it would impose stricter standards for contamination.

“We found that large amounts of dirty wastes or even hazardous wastes are mixed in the solid waste that can be used as raw materials,” the WTO notification states. “This polluted China’s environment seriously.”

Hamm has typically sent about 1,000 tons of recyclable material annually to China, which represents about 10 percent of Hamm’s output, according to Sedlock. He said Hamm pre-emptively shifted away from exporting material to China after the ban was announced last summer and found other buyers for those recyclables.

Exactly how the ban and shifting demand of the global recycling market will play out in Lawrence is yet to be seen.

The city’s solid waste fund is an enterprise fund, meaning that fees and operations are set up to cover costs. Solid Waste Director Kathy Richardson said that according to the city-Hamm contract, Hamm may adjust the city’s processing fee annually.

Richardson said the processing fee began at $45 per ton and is now $45.71. She said if that fee increases, it can affect the residential solid waste rates. She noted the City Commission approves all rate increases annually.

Specifically, Sedlock said the lower prices for material affect the rebates that Hamm and the city receive for recyclables. Sedlock said the rates of materials change monthly and it’s too early to say what the trend will be. He said if the recycling industry adjusts and more material is processed in the United States, it may even have some positive effects in the long run.

As far as any buildup of material, Sedlock said Hamm has no “out of the ordinary” stockpiles and they are confident that the low contaminate level of the material produced by Hamm — it uses a multistep sorting and decontamination process — will keep its material marketable.

“We’re confident in our processing capability to generate high quality recycling without contamination,” Sedlock said. “And that’s something we’ve been doing since day one.”

Still, he said it’s important that residents do their part in keeping recycling clean.

In the past, material that cannot be recycled, such as Styrofoam, small pill containers, plastic bags and bottle caps, have contaminated recycling at Hamm. A full list of the materials accepted as part of the city’s single-stream recycling pickup is available on the city’s website.