From 1950 to 1994, the U.S. Army operated a radio transmitting station and electronics research facility on this site. This cold-war-era military base was the heart of Army communications and electromagnetic pulse research. In 1995, the entire 580-acre facility was transferred to the U.S. Fish and Wildlife Service and became the Occoquan Bay National Wildlife Refuge. The footprint of the former Harry Diamond Laboratory is now restored to grassland, and although much of the Army's presence on the refuge has been removed, remnants such as power poles, power and communications conduit, and concrete supports are still visible.