Bush said he selected Leavitt, 52, "because he is a trusted friend, a capable executive and a man who understands the obligations of environmental stewardship.

"As co-chair of the Western Regional Air Partnership, Governor Leavitt has been a leader in applying high standards in air quality, and he understands the importance of clear standards in every environmental policy."

Governor Leavitt said he believed in "libra. It's a latin word. It means to move toward balance. To me, there is an inherent human responsibility to care for the earth. But there's also an economic imperative that we're dealing with in a global economy to do it less expensively."

Leavitt's nomination drew mixed reviews. Business interests described him as a consensus-builder and a moderate. Environmental groups said he supported development over conservation.