American Centrifuge Reaches One-Million Hour Milestone

USEC
Inc. (NYSE:USU) today announced that its American
Centrifuge project for uranium enrichment has surpassed one million
hours of machine run-time in its Lead Cascade test program. USEC has
operated centrifuge machines at its American Centrifuge Demonstration
Facility in Piketon, Ohio since August 2007.

'One million hours of run-time is a testament to the robustness of this
leading-edge technology and a great accomplishment for our team,? said
Dan Rogers, general manager of American Centrifuge Plant operations.
'With this experience in the demonstration facility, we have improved
the technology and gained extensive knowledge and operating data.?

USEC continues work on a research, development and demonstration (RD&D)
program proposed by the Department of Energy (DOE) to enhance the
technical and financial readiness of the centrifuge technology for
commercialization.

'One million hours of run-time gives us great confidence in the machine
technology and design. The RD&D program that we are working on will
provide further demonstration of the technology′s readiness for
commercialization and serves as a bridge to commercial deployment,?
added John K. Welch, USEC president and chief executive officer.

The proposed RD&D program scope is to construct and operate a
demonstration cascade of 120 commercial centrifuge machines. The RD&D
program is expected to establish the high-confidence level in cascade
reliability required by DOE to support loan guarantee financing for the
commercial plant. The RD&D program will also build out and demonstrate
the redundant cascade support systems that will be installed in the
commercial plant.

USEC has already invested more than $2 billion in the American
Centrifuge project, and will continue funding the RD&D program through
the end of May. After May 31, the company′s credit facility will impose
tight restrictions on American Centrifuge project spending absent a
definitive agreement with DOE for federal funding of the RD&D program.
While Congress is pursuing program funding as part of the fiscal year
2013 budget process, federal funding for the RD&D program is not yet
available from June 1 through October 1. Without federal funding, USEC
will likely begin to demobilize the project in June.

When commercially deployed, the American Centrifuge project will support
approximately 8,000 jobs across the country, especially in Ohio,
Pennsylvania, West Virginia, Alabama, Tennessee, Michigan and Indiana.
It will also preserve the U.S. government′s ability to produce enriched
uranium to support U.S. national security needs.

USEC Inc., a global energy company, is a leading supplier of enriched
uranium fuel and nuclear industry related services for commercial
nuclear power plants.

Forward Looking Statements

This news release contains 'forward-looking statements? within the
meaning of Section 21E of the Securities Exchange Act of 1934 ? that is,
statements related to future events. In this context, forward-looking
statements may address our expected future business and financial
performance, and often contain words such as 'expects?, 'anticipates?,
'intends?, 'plans?, 'believes?, 'will? and other words of similar
meaning. Forward-looking statements by their nature address matters that
are, to different degrees, uncertain. For USEC, particular risks and
uncertainties that could cause our actual future results to differ
materially from those expressed in our forward-looking statements
include, but are not limited to: risks related to the ongoing transition
of our business, including uncertainty regarding the transition of the
Paducah gaseous diffusion plant and uncertainty regarding continued
funding for the American Centrifuge project and the impact of decisions
we may make in the near term on our business and prospects; the outcome
of ongoing discussions with DOE regarding the RD&D program, including
uncertainty regarding the timing, amount and availability of funding for
such RD&D program and the dependency of government funding on
Congressional appropriations; restrictions in our credit facility on our
spending on the American Centrifuge project after May 31, 2012 and the
potential for us to demobilize the project; the impact of any conditions
that are placed on us or on the American Centrifuge project in
connection with or as a condition to the RD&D program or other funding,
including a restructuring of our role and investment in the project;
limitations on our ability to provide any required cost sharing under
the RD&D program; the ultimate success of efforts to obtain a DOE loan
guarantee for the American Centrifuge project, including the ability
through the RD&D program or otherwise to address the concerns raised by
DOE with respect to the financial and project execution depth of the
project, and the timing and terms thereof; the impact of actions we have
taken or may take to reduce spending on the American Centrifuge project,
including the potential loss of key suppliers and employees, and impacts
to cost and schedule; the impact of delays in the American Centrifuge
project and uncertainty regarding our ability to remobilize the project;
changes in U.S. government priorities and the availability of government
funding, including loan guarantees; uncertainty regarding the continued
capitalization of certain assets related to the American Centrifuge
Plant and the impact of a potential impairment of these assets on our
results of operations; and other risks and uncertainties discussed in
our filings with the Securities and Exchange Commission, including our
annual report on Form 10-K and quarterly reports on Form 10-Q, which are
available on our website at www.usec.com.
We do not undertake to update our forward-looking statements except as
required by law.

USEC Inc.

Media: Paul Jacobson, 301-564-3399

Investors: Steven
Wingfield, 301-564-3354