Environmental Protection Agency Administrator Scott Pruitt on Tuesday discussed plans, with the help of the Army Corps of Engineers, to propose repeal of the Clean Water Rule during a Senate hearing to review the proposed EPA budget for fiscal year 2018.

Pruitt cited the executive order President Donald Trump signed in February to review the Clean Water Rule and “propose to rescind or revise the rule as appropriate and consistent with the law and to ensure that we are meeting the original goals and policies of the Clean Water Act as Congress has established,” Pruitt’s written statement to the committee read.

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What is the Clean Water Rule?

The Clean Water Rule, or the Waters of the United States, was added to the Clean Water Act in 2015 to clarify which waters were protected under the Clean Water Act of 1972. The Clean Water Act was known as the Federal Water Pollution Control Act of 1948 before it was amended in 1972 to include stricter regulations.

The Clean Water Rule made it clear that waters feeding rivers, like streams and wetlands, also were to be protected under the act. There had been confusion about which waters were specifically protected, and after years of requests from members of Congress, local elected officials, environmental and agricultural groups and others, the rule was added, a release said. The goal of the rule is to safeguard the drinking water of 117 million Americans who get their water from waterways that previously were unprotected by the initial act.

President Trump and Scott Pruitt want to get rid of the rule, Trump’s executive order and Pruitt’s statement Tuesday indicated. The executive order said the rule needed to be reviewed to ensure its consistency in “promoting economic growth, [and] minimizing regulatory uncertainty.

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New Mexico Sen. Tom Udall, who sits on the committee that was hearing the budget proposal, tweeted his disapproval of Pruitt’s “inability to articulate this admin’s position on #ClimateChange.”

Pruitt’s statement comes just weeks after President Trump pulled the United States from the Paris Climate Agreement, a move elected officials and companies nationwide protested by signing statements committing their jurisdictions and firms to the agreement anyway.

Pruitt and other officials in the Trump administration have expressed doubts about the science of climate change. President Trump once called global warming a “hoax” and “bullshit.” Pruitt said he does not believe climate change is caused by increased levels of carbon dioxide even though 97 percent of scientists agree it is caused by the CO2 released by human activity. Energy Secretary Rick Perry also shares this doubt, which he discussed on CNBC last week.