The effects of Congress' fiscal noose are beginning to show at U.S. EPA: To save on security costs, officials are closing three staff-only entrances to its Washington, D.C., headquarters.

Spokeswoman Alisha Johnson said the move will save EPA $300,000 annually. The doors will remain functional for emergencies, but their closure will mean fewer security guards to pay.

"This is an EPA decision driven by the need to cut costs and budget reductions," she said in an email. "EPA has carefully considered this action in order to reduce the extent of inconvenience to employees and visitors while retaining sufficient, safe and reasonable entrances to support agency and public needs."

The agency's headquarters sits in the Federal Triangle and comprises several buildings, including the main Ariel Rios Federal Building. The three least-used entrances will be closed starting this weekend: the Ariel Rios South entrance that opens to the Woodrow Wilson Plaza; the EPA East entrance on 12th Street NW; and the Ariel Rios North interior employee entrance at the corner of 12th Street NW and Pennsylvania Avenue NW.

As lawmakers debate over fiscal 2012 and 2013 budgets -- and how to find the $1.5 trillion in cuts required by August's debt ceiling deal -- the fiscal future at federal agencies remains uncertain. EPA's position is particularly precarious, as GOP lawmakers continue to criticize its regulatory role.

Last month, the Office of Management and Budget directed agencies to cut costs by 5 percent in their fiscal 2013 budget requests, and agencies are already downsizing in the face of tight budgets.