Depleted Uranium Hexafluoride (DUF6) has been produced in the United States as part of the process of enriching natural uranium for both civilian and military applications since the early 1950s. Production took place at the three gaseous diffusion plants (GDPs), constructed to enrich uranium, first at the K-25 site (now called ETTP located in Oak Ridge, TN) and subsequently at Paducah, KY and Portsmouth, OH. The K-25 plant ceased operations in 1985, and the Portsmouth plant ceased operations in 2001. The Paducah GDP continues to operate.

Before 1993, all DUF6 in the U.S. was generated by the government. In 1993, the U.S. government began the process of privatizing uranium enrichment services by creating the United States Enrichment Corporation (USEC).

As a result of two memoranda of agreement signed by USEC and DOE in 1998, and another agreement signed
in 2002, a certain amount of DUF6 generated by USEC after 1993 has already been transferred or will be
transferred to DOE.

The Paducah site has about 440,000 MT DUF6 stored in 36,200 cylinders. The Portsmouth site will have about 250,000 MT DUF6 stored in 16,000 cylinders from the Portsmouth facility and 4,800 cylinders transferred from ETTP.

Continued storage of the DUF6 cylinders at the three GDP sites raised concerns by the Defense Nuclear Facilities Safety Board, and the three States where the GDPs are located. As a result, DOE has established a more aggressive approach for the management and disposition of the cylinders and their contents.

In 2002, DOE awarded Uranium Disposition Services, LLC (UDS) the contract to design, build, and operate two DUF6 conversion plants based on the proven DUF6 conversion technology and team member skill sets. UDS consists of three companies: Duratek Federal Services, Inc., Burns and Roe Enterprises, Inc., and Avera Framatome ANP, Inc.

The facilities at Portsmouth and Paducah will convert
DUF6 into uranium oxide for disposal or an alternate use
and aqueous hydrogen fluoride which will be sold.