Washington (CNN) Newly released emails appear to contradict EPA Administrator Scott Pruitt's account in recent congressional testimony that the aide who assisted him with his apartment hunt did so "on personal time."

The emails, released by three Democratic senators who have been investigating Pruitt's actions at the Environmental Protection Agency, show a scheduler in Pruitt's office corresponded with a real estate agent during typical work hours.

Her assistance in the housing search has drawn attention because of Pruitt's previous $50-per-night lease, a below-market-rate arrangement with a lobbyist couple, one of whom represented clients before the EPA, and because she received two raises in her first year at the agency, together boosting her pay by 72%.

"It's my understanding that all activity there was on personal time," Pruitt said at a hearing two weeks ago. The aide, who he described as "a longtime friend of my wife and myself," was not paid for the work, Pruitt said.

Sens. Tom Udall, Tom Carper, and Sheldon Whitehouse released the emails on Thursday along with a letter asking for an inspector general probe of the matter. The EPA inspector general has previously acknowledged concerns with the condo and the "use of the Administrator's subordinates' time," but has not announced whether he will perform a full review.

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