BETHESDA, Md. - USEC Inc. (NYSE: USU) officially notified the Department of Energy (DOE) in a letter today that its Portsmouth Gaseous Diffusion Plant in Ohio ceased production of enriched uranium on Friday, May 11, 2001. USEC has leased the facility from DOE since 1993 for the purpose of enriching uranium to make fuel for commercial nuclear power plants.

The company’s plans to consolidate its enrichment operations at one plant – its Paducah, KY plant – were publicly announced in June 2000.

“The Portsmouth employees have shown a strong commitment to safety and a high degree of professionalism in their work to conclude enrichment operations at the plant,” said William H. Timbers, USEC President and CEO. “I commend all of them for their hard work and appreciate their professional attitudes.”

USEC Inc., a global energy company, is the world’s leading supplier of enriched uranium fuel for commercial nuclear power plants.

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