Oak Ridge Reservation Fact Sheet

The mission of NCSL’s Nuclear Legislative Workgroup (NLWG) is to provide legislative members with the opportunity to learn about the cleanup of federal nuclear weapons production and research facilities, the transportation and storage of radioactive wastes, and nuclear energy issues that affect our nation and states. This fact sheet is part of this effort.


The Oak Ridge Reservation (ORR) in East Tennessee originally operated as a gaseous diffusion plant that produced enriched uranium for nuclear weapons during the Manhattan Project and the Cold War. The 37,000 acre reservation consists of three major campuses that have diverse operations. The U.S. Department of Energy’s Environmental Management (DOE-EM) and National Nuclear Security Administration oversee cleanup activities at the site, which began in 1989.

State:  TN
Size: 37,000 acres
Original Purpose: Uranium, Lithium, and Plutonium Production
Estimated Cleanup Completion: 2015

Scale of the Contamination

The DOE originally initiated about 50 remedial activities at ORR. There are three primary cleanup sites at ORR: (1) Oak Ridge National Laboratory, (2) Y-12 National Security Complex, and (3) East Tennessee Technology Park. Two million pounds of mercury were discharged into the environment, contaminating soils, groundwater, air, and the East Fork Polar Creek. Unlined burial grounds, pits, and more than 100 underground waste tanks have contaminated groundwater. Low-level and mixed wastes were stored in over 27,000 containers, and 3,500 cubic meters of Transuranic (TRU) wastes existed on site.

DOE Environmental Management Activities

The DOE EM’s mission at ORR is to improve the reservation’s environment through remediation and decontamination while reducing the risk of potential exposure.
East Tennessee Technology Park

  • K-25 demolition. Demolition of the massive K-25 uranium enrichment facility, once the world’s largest building under one roof, is expected to finish in 2014, at which time the 44-acre site will become a private industrial park.
  • K-27 demolition. Also a massive former uranium enrichment facility, the K-27 building is currently being prepped for demolition. The facility presents a major radiological challenge with some areas contaminated with technetium-99, a slow-decaying radioactive metal. The building also contains high-risk equipment that must be removed.

Oak Ridge National Laboratory

  • Building 3026. The site of a radioisotope development laboratory during the Manhattan Project, Building 3026 contained six radioactive hot cells. EM has completed demolition of the outer structure of the building and has removed four of the hot cells.  
  • Uranium-233. DOE is working on removing the significant inventory of Uranium-233 at the Oak Ridge National Laboratory. The inventory is being evaluated to determine what can be used for other programmatic purposes and what can be disposed of directly.

Y-12 National Security Complex

  • Remediation of Upper East Fork of Poplar Creek. DOE is conducting multiple projects to identify mercury sources and lessen the flow of mercury into the groundwater. The ongoing work includes remediating the soil, sediment and buried materials at the site.
  • Alph-5 and Beta-4 demolition. These two buildings housed uranium processing equipment and mercury enrichment or lithium production operations. Both buildings have been prepped for demolition.

TRU Wastes
Transuranic (TRU) wastes are a mixed byproduct of nuclear production and research consisting of protective gear, tools, residue, debris, and other items. In 2003 the TRU Waste Processing Facility was constructed to treat, package, and dispose of TRU waste from the site. The TRU wastes are transported to the Waste Isolation Pilot Plant in New Mexico. The TRU processing facility did not meet the expected goals of 2011 and have been revised to a final legacy waste disposal date of 2016.
Environmental Waste Management Facility
The Environmental Management Waste Management Facility disposes of wastes generated from the cleanup. The facility is predicted to reach capacity before ORR completes its cleanup. As a result, the construction of a new on-site disposal facility is now being considered.
Chromium Water Treatment System
The Chromium Water Treatment System began operations in 2012. The system provides a long-term solution to chromium contaminated groundwater affecting Mitchell Branch, East Fork Poplar Creek, and the Clinch River.

Timeline for Cleanup Completion

The overall site cleanup is estimated to continue until 2022. Some of the work may take longer due to uncertainties. In 2017 the National Nuclear Security Administration and DOE’s Office of Science will transfer a large amount of facilities to EM.

Other Activities

Oak Ridge National Laboratory
The Oak Ridge National Laboratory, formerly known as X-10, is a multipurpose laboratory supporting research, science, technology, supercomputing, energy, and national security. The laboratory has nine facilities, including the High Flux Isotope Reactor and the Spallation Neutron Source, offering advanced research to scientists and universities.
Y-12 National Security Complex
The complex ensures national security by nuclear nonproliferation, disassembling nuclear weapons, and storing nuclear materials. Y-12 also serves as the National Prototype Center, manufacturing complex items for federal government agencies. Y-12 is now following a Ten Year Plan to modernize the facility for future beneficial use.