President Trump on Thursday nominated Andrew R. Wheeler, a coal lobbyist with links to outspoken deniers of established science on climate change, to help lead the Environmental Protection Agency.

In announcing Mr. Wheeler, a former aide to Senator James M. Inhofe, to be deputy administrator of the agency, the White House tapped an experienced legislative hand reviled by environmental activists but hailed by industry as having the know-how to dismantle Obama-era fossil fuel regulations.

The nomination comes at a critical moment for the E.P.A. as the agency prepares to repeal a sweeping climate change regulation known as the Clean Power Plan. It would also fill a key high-level position at the agency, where many top offices remain vacant. If confirmed by the Senate, Mr. Wheeler would become the most powerful person at the agency behind its administrator, Scott Pruitt.