The Supreme Court seemed prepared on Tuesday to rule that a federal agency had done enough to consider the environmental impact of a proposed 88-mile railway in Utah. Such a ruling could limit the scope of environmental reviews required by federal law in all sorts of settings.

The proposed railway would connect oil fields in the Uinta Basin in northeast Utah to a national rail network that runs next to the Colorado River and then to refineries on the Gulf Coast.

The Surface Transportation Board, a federal agency that regulates rail transportation, approved the Utah project after conducting a review that yielded a 3,600-page report. Environmental groups and a Colorado county sued, saying the report had not taken account of some ways in which the railway could do harm to the environment.

The U.S. Court of Appeals for the District of Columbia Circuit ruled for the challengers.

Paul D. Clement, a lawyer representing seven Utah counties in support of the project, said that “the board was not heedless of environmental effects here.”

“It consulted with dozens of agencies, considered every proximate effect and ordered 91 mitigation measures,” he added. “Eighty-eight miles of track should not require more than 3,600 pages of environmental analysis.”

More generally, Mr. Clement said that agencies should not be required to consider effects of projects that are “remote in time and space” and where other regulators have responsibilities.