The head of the Environmental Protection Agency claims her agency was basically powerless to deal with the Flint, Mich., lead water crisis due to the state's failures, prompting the House oversight chairman to say, "You just don't get it."

EPA Administrator Gina McCarthy said Thursday that on July 21, 2015, the EPA told the Michigan Department of Environmental Quality that they needed to get a handle on the lead water situation in the city of 100,000 people.

"They said we'll do it and since that point in time the MDEQ slow walked everything they needed to do," she said. "That precluded us from being able to jump in to the rescue."

That response so frustrated House Committee on Oversight and Government Reform Chairman Jason Chaffetz that he interrupted McCarthy's comments.

"Wow. You just don't get it. You just don't get it. You still don't get it," he said.

McCarthy and Michigan Gov. Rick Snyder appeared in front of the committee to testify about the lead water crisis in Flint that began in April 2014, when a state emergency manager appointed by Snyder signed off on a symbolic vote from the Flint City Council to change the city's water source.

The move aimed to cut costs by requiring the city to take its water from the Flint River instead of the Detroit Water and Sewerage Department while a new pipeline was built to connect the city to Lake Huron.

The Flint River water, however, was so acidic that it caused the lead pipes bringing water from the city's cast iron mains into homes to corrode. Lead leached off the pipes and into the drinking water throughout the city.

The state and the federal government have declared a state of emergency, and Flint residents are not able to drink the water coming out of their taps.

It's the third hearing the committee has held on the lead water crisis in Flint.

Rep. John Mica, R-Fla., had harsh words for McCarthy on the EPA's culture of accountability.

He said Snyder has fired somebody for their role in the crisis, but no one at the EPA has been held accountable. Susan Hedman, the leader of the regional office resigned and McCarthy refused to say on Thursday if she would have fired Hedman.

Mica said the EPA stood by and let the crisis happen despite one EPA researcher knowing something was wrong and making a report.

"It's incredibly accurate. This is dated in June and not a damn thing was done until, really, January of this year," she said.