A top aide to Environmental Protection Agency Administrator Scott Pruitt has resigned from the agency after telling a congressional committee that she was asked to obtain a used mattress from the Trump International Hotel in Washington.

Hupp issued her resignation, and her last day will be Friday.

Hupp serves as Pruitt's director of scheduling as a number of scandals have emerged over his travel and security spending. More than a dozen investigations on Pruitt's spending are under way.

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One top EPA official told the Atlantic, which first reported the news, that the 26-year-old Hupp was “tired of being thrown under the bus by Pruitt” and grew weary of her name appearing in headlines about the EPA.

"I’ve had the opportunity to know Millan for the last several years as a colleague, friend and trusted partner. She has done outstanding work in all of her endeavors here and will be sorely missed. I wish her all the best," Pruitt said Wednesday.

In March, Hupp was one of two aides who received large salary increases from Pruitt after the White House denied the request for pay raises.

The Washington Post reported Monday that Hupp testified before the House Oversight and Government Reform Committee that she regularly did personal tasks for Pruitt, from looking for housing to calling the Trump Hotel about acquiring a used mattress.

The White House said this week that it was looking into the mattress matter.

EPA spokesman Jahan Wilcox would not comment on the resignation. He instead called Elaina Plott, the Atlantic staff writer, a "piece of trash," the Atlantic reported.

Meanwhile, congressional Democrats tried to attach riders to the EPA's fiscal 2019 appropriations bill, seeking to hold Pruitt accountable.

One rider sought to mandate the administrator's travel be disclosed 10 days beforehand. Another rider sought more funding for the EPA inspector general to probe Pruitt's actions. Both riders failed to be included, along strict party-line votes.