A private waste management company looking to expand in Maine is guaranteeing that communities that sign on to its pay-as-you-throw waste disposal system will reduce the amount of trash they must dispose of by one-third within a year of making the switch.

WasteZero, a North Carolina-based company, announced the promotion Wednesday in partnership with the Natural Resources Council of Maine, the state’s largest environmental advocacy group.

The company administers pay-as-you-throw trash programs across the U.S. including more than 40 communities in Maine. This is the first time WasteZero has offered its guarantee to all communities in a state, said chairman John Campbell.

“We think that Maine could be the greenest state in the U.S. from a solid waste perspective,” said Campbell.

Many towns and cities in the U.S., including several in Maine, have adopted pay-as-you-throw programs, also called waste metering, to create an incentive for residents to recycle and compost and reduce the amount of trash they must pay to dispose of.

Programs commonly require residents to buy a specific kind of colored trash bag to dispose of their waste, with the cost varying by community. In Waterville, where a pay-as-you-throw system is already in place, residents pay $2 each for large trash bags and $1.25 each for small ones. In Portland, residents pay $2.70 for 30-gallon bags and $1.35 each for 15-gallon bags.

“It is shifting costs in a way, but the cost is more direct,” said Sarah Lakeman, sustainability director at Natural Resources Council of Maine. “The cost is coming out of their wallets, people get a sense of accountability for the waste they produce.”

WasteZero is promising that communities will reduce the waste they produce by 35 percent in the first year after implementing the company’s program. If it doesn’t hit that guarantee, the company will pay for the remainder. The deal is aimed at communities with curbside trash pickup, but can work in places where residents take their waste to a transfer station, Campbell said.

The 42 Maine communities that work with WasteZero experienced an average 44 percent reduction in waste with the program, according to the company. Offering a guarantee can ease concerns for towns and cities that feel putting the time and research into a pay-as-you-throw program might not be worth it, said Craig Dunkley, a senior vice president for the company.

The company’s offer comes as the solid waste disposal landscape in the state is shifting. Almost 190 communities in central and eastern Maine whose long-term disposal contracts are up in 2018 were courted by competing waste-to-energy proposals, including one for a new biomethane plant in Hampden. That proposal is opposed by the Natural Resources Council of Maine and some legislators who claim it would violate Maine’s solid waste policy because it prioritizes energy production over waste reduction and recycling.

The uncertainty has led some communities to inquire about different solid waste options, Campbell said.

Many southern Maine cities and towns that send their waste to the ecomaine recycling and a waste-to-energy plant in Portland already use pay-as-you-throw. The company believes that approach is gaining momentum and more communities are moving toward the system, Campbell said.