A U.S. Department of Energy official is visiting South Carolina's former nuclear weapons complex to celebrate a milestone in stimulus-funded cleanup.

Officials say U.S. Department of Energy Assistant Secretary for Environmental Management Ines Triay is at the Savannah River Site on Wednesday to mark the completion of work at the M Area.

Savannah River opened in the early 1950s and once produced plutonium and tritium for atomic bombs. The M Area was once used for reactor fuel production. Now, work at the U.S. Energy Department site is focused mostly on research and environmental cleanup.

The site received $1.6 billion in stimulus cash to create and save about 3,000 jobs for environmental cleanup work.