The Supreme Court struck down some of EPA's rules regulating the discharge of treated sewage. The rules allegedly enforced the Clean Water Act. In a 5-4 decision, with Justice Amy Coney Barrett crossing to join three progressive justices, the Supreme Court ruled that the EPA can't play Humpty Dumpty and say the legal standard "means just what I choose it to mean — neither more nor less."

It started when the EPA fined the City of San Francisco nearly $10 billion because of alleged violations of its sewage discharge into the Pacific Ocean. There were $313 million in assessed fines and about $10.6 billion in mandated upgrades to its treatment plant. San Francisco did not deny that the EPA had the authority to police sewage discharge; its objection was that the standards were so vague that the city could not meet them because they were forever shifting.

“We simply want to understand our prohibition limits so we can comply with them,” Tara M. Steeley, the San Francisco deputy city attorney, told the justices.

This is how Justice Alito described the situation in his opinion.

Instead, this case involves provisions that do not spell out what a permittee must do or refrain from doing; rather, they make a permittee responsible for the quality of the water in the body of water into which the permittee discharges pollutants. When a permit contains such requirements, a permittee that punctiliously follows every specific requirement in its permit may nevertheless face crushing penalties if the quality of the water in its receiving waters falls below the applicable standards. For convenience, we will call such provisions “end-result” requirements. //

This case marks the latest entrant in the list of court cases that roll back the incredible authority that the EPA has arrogated to itself to manage the US economy.