The year 2017 marks 40 years since the U.S. Department of Energy (DOE or Department) was established to unify the federal government’s energy planning efforts. Since its activation on October 1, 1977, the Department—bolstered by dedicated personnel like Environmental Justice Program Manager Melinda Downing, who has been with DOE since its inception—has ensured America’s security and prosperity by addressing the nation’s energy, environmental, and nuclear challenges through transformative science and technology solutions.

The roots of DOE, however, trace back much further to World War II, when the U.S. Army Corps of Engineers established the Manhattan Engineer District to develop and build the atomic bomb. The Manhattan Project built uranium isotope separation facilities at Oak Ridge, Tennessee; plutonium production reactors at Hanford, Washington; and a weapons laboratory at Los Alamos, New Mexico. Numerous additional sites across the nation supported these efforts. The project culminated with the United States dropping atomic bombs on Hiroshima and Nagasaki, Japan, in early August 1945. The Japanese emperor announced Japan’s surrender on August 15, 1945.

After World War II, Congress sought to promote the peaceful use of atomic energy and placed weapons production under civilian control. President Truman signed the Atomic Energy Act of 1946, conveying Manhattan Project assets and responsibilities to the civilian U.S. Atomic Energy Commission (AEC). Soon after, the United States government transferred all atomic energy activities to the newly created commission. During the early Cold War years, AEC oversaw design and production of nuclear weapons, developed nuclear reactors for naval propulsion, and regulated the new commercial nuclear power industry.

By the 1970s, AEC faced increasing criticism for serving as both the regulator and promoter of the atomic energy industry. At the same time, a growing energy crisis underscored the necessity to develop a coordinated national energy policy and concentrate the government’s various energy programs into one agency. President Gerald Ford signed the Energy Reorganization Act of 1974, abolishing the AEC and establishing the Energy Research and Development Administration (ERDA) and the U.S. Nuclear Regulatory Commission. In 1975, the president activated ERDA, and the agency assumed responsibility for the AEC nuclear weapons program.

As the energy crisis of the 1970s deepened, the government explored ways to consolidate the nation’s fragmented energy program to maximize efficiency. In 1977, President Carter signed the Department of Energy Organization Act, which abolished ERDA and the Federal Energy Administration and established the U.S. Department of Energy as the 12th cabinet-level department.

With the end of the Cold War and resulting reduction in nuclear build-up, the primary missions of many nuclear weapons production sites shifted to environmental remediation. In 1989, DOE created the Office of Environmental Restoration and Waste Management, which later was renamed the Office of Environmental Management (EM). EM’s mission is to complete the safe cleanup of nuclear waste, materials, and facilities left over from five decades of nuclear weapons development and government-sponsored nuclear energy research.

In the 1990s, there was a growing realization within DOE that there would still be residual risk at some Manhattan Project and Cold War legacy sites, even after cleanup. As part of the cleanup effort, DOE had installed a variety of environmental remedies, some requiring long-term surveillance and maintenance.

As a result, in 2003 DOE established the Office of Legacy Management (LM) to fulfill the Department’s cleanup responsibilities at sites no longer needed for DOE missions. Former Energy Secretary Spencer Abraham stated that the “establishment of the Office of Legacy Management demonstrates the Department’s continued commitment to manage sites where active remediation has been completed, as well as our commitment to the contractor workforce that will be affected by changing Departmental missions.”

As of March 2017, LM is responsible for 92 sites in 28 states and the territory of Puerto Rico, with more sites expected to transfer to LM post-cleanup. Although LM will only be 14 years old this December, it has the responsibility for the protection of human health and the environment at sites that trace their histories back to the Manhattan Project and the nation’s early atomic energy program.

“Legacy Management is dedicated to keeping the promises made to the workers who helped our country win the Cold War and to protect the health, safety, and the environment in the communities where this work occurred,” said LM Director Carmelo Melendez. “We are thankful for the support we enjoy within the Department and from political leaders and community organizations that help ensure that we will have the necessary resources to fulfill our mission now and in the future.”