Boeing has a carbon emissions problem. Startup Charm Industrial is cleaning up.

Boeing has signed a deal with startup Charm Industrial to remove 100,000 metric tons of carbon from the atmosphere.

Charm collects agricultural and forestry waste and uses heat to turn it into a product it calls “bio-oil,” a messy mixture of hydrocarbons that it injects underground, including into former oil wells. Once isolated, Charm can sell carbon removal credits to businesses. Axios first reported on the startup’s deal with Boeing.

Aviation has made little progress in reducing carbon emissions. This has left companies in this sector looking for alternatives. Decarbonization has emerged as a contender because it may be less expensive than switching to sustainable aviation fuel.

By 2050, one study found that the aviation industry will need to spend at least $60 billion on carbon offsets to reach net-zero emissions.

Charm can also produce biochar, a material that when applied to agricultural fields can help boost soil productivity, though such efforts are still in their infancy, according to data from the Isometric Carbon Removal Registry.

The financial terms of the deal were not disclosed. Two years ago, Charm sold 112,000 carbon removal credits to Frontier, an advanced market compliance company, for $53 million, or about $470 per metric ton. Charm said it wants to get the cost down to about $50 per metric ton.