WASHINGTON – The Environmental Protection Agency’s Lisa Jackson, who headed up the agency while it developed the new federal fuel economy rules that set a goal of 54.5 mpg by 2025, is leaving the Obama administration after four years. She issued a statement on Dec. 27, 2012, announcing her intent to leave.

In response to Jackson’s announcement, the White House issued a statement wishing her well and noting her contribution to the new fuel economy rules, among other regulations. The White House has not yet announced a replacement.