Birnbaum was in charge of administering "programs that ensure the effective management of renewable energy [...] and traditional energy and mineral resources on the nation's Outer Continental Shelf, including the environmentally safe exploration, development, and production of oil and natural gas, as well as the collection and distribution of revenues for minerals developed on federal and American Indian lands.

[2][3] From 1991 to 1999 she was counsel to the House Committee on Natural Resources, where she handled legislative and oversight activities for the Department of the Interior, U.S. Forest Service, and electric power marketing administrations.

[5] In addition, she was a special assistant to the Interior Solicitor, from 1999 to 2000, overseeing legal policy on a range of natural resource issues, including mining law, public land management and hydropower licensing.

The resignation came during the controversial Deepwater Horizon oil spill and Salazar's subsequent announcement that the Minerals Management Service would be reorganized.

[20] On April 17, 2014, Birnbaum co-authored an opinion editorial in The New York Times with Jacqueline Savitz titled "The Deepwater Horizon Threat".