Iowa regulators will begin a permit hearing for the country's largest proposed carbon pipeline in August, a timeline that the project's opponents, including environmental groups and landowners, say doesn't give them adequate time to prepare.

Whether Iowa-based Summit Carbon Solutions can obtain a permit in its home state, which would house the most pipeline miles of its proposed 2,000-mile, five-state route, is a critical test for the company and the carbon capture and storage (CCS) industry.

The administration of President Joe Biden has said CCS is key to cutting U.S. greenhouse gas emissions. The ethanol industry is betting heavily that CCS pipelines like Summit's will secure the fuel's place in the increasingly climate-conscious transportation sector.

The Iowa Utilities Board (IUB) on June 16 announced that Summit's permit hearing would begin on Aug. 22 and could last for months as the board hears from the company and other participants in the regulatory process.

Summit told Reuters it supports the timeline. The company expects its pipeline to be operational in 2024, according to its website.

Opponents of the project argued at a June 20 press conference that August is too soon for landowners who may be subject to eminent domain to prepare testimony or retain attorneys.

The owners of more than 1,000 plots of land along the proposed Summit route have not yet signed easements with the company, said Jess Mazour, an organizer with the Iowa Sierra Club.

Under Iowa law, if Summit receives a permit it could take that land through eminent domain.

"We need to make sure it’s a fair process," Mazour said of the IUB schedule.

Summit has signed more than 2,000 easements, agreements to pay fees to use property, with landowners along 475 miles of its 688-mile Iowa route, it told Reuters.

Dan Wahl, a farmer living along the proposed Summit route in Dickinson County who has not signed an easement, said he and other farmers could struggle to participate in the hearing as they could be preoccupied with the farm season in late August.

Opposition groups plan to file briefs challenging the hearing schedule this week, Mazour told Reuters.