The Environmental Protection Agency will review the definition of “waters of the United States,” pledging to follow a U.S. Supreme Court ruling that shortened the reach of the Clean Water Act.

Speaking in Atlanta, EPA Administrator Lee Zeldin said March 12 he wanted to “fix” the definition “once and for all” with something “simple and durable.”

“We are not looking for this to be a ping-pong,” he said.

The Clean Water Act regulates the discharge of pollutants into waters of the United States, or WOTUS. The WOTUS definition has shifted with White House polices and court decisions.

The Supreme Court’s Sackett v. The Environmental Protection Agency decision limited the Clean Water Act to larger bodies of water, rather than extending it to isolated wetlands.

To date, the EPA has failed to implement the Supreme Court’s decision, according to a statement by the agency. The scope of the law determines when farmers and other landowners must obtain federal permits for projects.

The EPA said it will work with the Army Corps of Engineers. According to the EPA, the definition will discard the “significant nexus” test, a way of defining WOTUS that came from an earlier Supreme Court, but critics said gave too much discretion to regulators.

Appearing with Zeldin, Sen. Kevin Kramer, R-North Dakota, said Sackett should have brought clarity to federal enforcement.

“There are a lot of people, including in the previous administration, who just ignored that clarity and sort of chose to make it sound murky,” he said.

Farmers have suffered regulatory whiplash, said Sen. Joni Ernst, R-Iowa. “We really do have to stop this,” she said.