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The Portsmouth plant enriched uranium from 1954 until 2001 through a process called gaseous diffusion.

The Portsmouth Gaseous Diffusion Plant operated from 1954 to 2001. Located in Pike County, Ohio, the plant occupies about 1,200 acres of the 3,777-acre federally-owned Portsmouth Site. The plant was one of three large gaseous diffusion plants in the United States initially constructed to produce enriched uranium to support the nation’s nuclear weapons program and, in later years, enriched uranium used by commercial nuclear reactors. After the Cold War, weapons-grade uranium enrichment was suspended and production facilities were leased to the private sector. In 2001, enrichment operations were discontinued at the site. 

DOE's Office of Environmental Management began its environmental cleanup program at the site in 1989 and the effort continues today in cooperation with the U.S. and Ohio Environmental Protection Agencies.  Decontamination and decommissioning (D&D) of the plant commenced in 2011 and is ongoing.  


Portsmouth Environmental Cleanup
Portsmouth Cleanup Program was established in 1989 to evaluate and take appropriate actions to ensure protection of human health and the environment.
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Portsmouth Environmental Monitoring
Timely information about DOE's program to detect and eliminate environmental hazards at or near the Portsmouth Site.
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Portsmouth D&D Program
The Decontamination & Decommissioning (D&D) Program at the Portsmouth Site addresses recent, current and planned demolition of facilities.
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Portsmouth Future Use
DOE's D&D project helps prepare the site for reuse, supporting the community’s vision to redevelop the Portsmouth Site property.
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Portsmouth Community Outreach
DOE is committed to fostering meaningful public involvement in environmental remediation decision-making at the Portsmouth Site.
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At His Day Job at EM’s Portsmouth Site, This Gamer Doesn’t Play
August 20, 2019
Zak Lafontaine is a world-class gamer.
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DUF6 Conversion Project Reaches Highest Plant Reliability Mark at Portsmouth Site
May 7, 2019
EM’s project to convert the nation’s inventory of depleted uranium hexafluoride to a more stable oxide form disposal recently achieved a milestone.
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DUF6 Conversion Project Meets Fiscal 2019 Goal Six Months Early
April 30, 2019
EM’s project to convert the nation’s inventory of depleted uranium hexafluoride to a more stable oxide form has reached its fiscal year.
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2019 DOE Public Tours Of Portsmouth Site Begin April 27
April 5, 2019
DOE is pleased to announce the 2019 public-tour dates for the former Portsmouth Gaseous Diffusion Plant in Pike County, Ohio.
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