SM-1 Stakeholder Update: May 2024

The SM-1 Project Team continues work on the SM-1 Decommissioning and Dismantlement project with APTIM AECOM Decommissioning, LLC (A2D) Joint Venture (JV) of Alexandria, VA.

The team completed the demolition of the Spent Fuel Pit and the above-grade Vapor Container structure, which previously housed the primary reactor system. The team completed the packaging of waste from this demolition effort in late-April. The team is now preparing to begin the demolition of the remaining building slab, foundations, footers and the below-grade utilities, and the below grade Spent Fuel Pit and Vapor Container structure. Additionally, the team continues to work on remediation of the site soils and is currently backfilling the remaining lower-site utility excavations areas with clean soil.

Decommissioning and remediation activities will continue through 2025. From there, the work will focus on site restoration and final project documentation, with an estimated project completion in August 2026.

The decommissioning contract includes all aspects of the project, including the removal of all reactor components; transportation and disposal of material; site cleanup; and restoration. The U.S. Army Corps of Engineers team continues to partner with our decommissioning contractor to ensure all aspects of the project are done with safety as the top priority. The USACE team overseeing the SM-1 decommissioning has a proven track record of safely carrying out a broad array of radiological projects around the world. This includes the complete decommissioning of one of SM-1’s sister reactors - the Army’s deactivated MH-1A nuclear reactor onboard the STURGIS vessel, which was the world’s first floating nuclear power plant and now the same team is implementing the decommissioning of the SM-1A, the sister plant in Alaska.  

Thank you all again for choosing to be a part of this process with us as progress with the decommissioning and dismantling of the deactivated SM-1. More project information is always available here on our project website.  As a reminder, we have a dedicated YouTube channel with videos for the Deactivated Nuclear Power Plant Program: Deactivated Nuclear Power Plant Program (DNPPP) - YouTube (includes videos for SM-1 and her sister site, SM-1A in Alaska). 

If you have any questions, feedback or information you’d like to share with us, please feel free to e-mail me or reach out to our Corporate Communications Office.

SM-1 Former Nuclear Power Plant Overview

The SM-1 Former Nuclear Power Plant is located on the western shore of the Potomac River within the boundaries of Fort Belvoir in Fairfax County, Virginia. It is approximately 17 miles south by southwest from the center of Washington D.C.

The construction of the SM-1 at Fort Belvoir was completed in 1957, and it achieved its first criticality in April 1957. The SM-1 was a single-loop 10 megawatt-thermal (MWt) pressurized water reactor delivering a net 1,750 kilowatts of electrical power. It was the first nuclear power reactor to provide electricity to a commercial power grid in the United States. The SM-1 Reactor operated from April 1957 to March 1973. Fort Belvoir was home to the U.S. Army Engineer Reactors Group (USAERG), and the SM-1 was used for training the multi-service crews that would operate the various plants in the program. The reactor was stationary with a medium power range, which was between 1,000 and 10,000 kilowatt-electric (kWe).

Deactivation was performed on the SM-1 Reactor from 1973-1974, in accordance with the SM-1 Decommissioning and Conversion Plan as approved by the Army Reactor Systems Health and Safety Review Committee (ARCHS). This consisted of removal of the nuclear fuel, minor decontamination, shipment of necessary radioactive waste, sealing the pressure vessel, and installing appropriate warning signs and monitoring devices.

After the completion of the facility deactivation and conversion, a third party radiological survey by the U.S. Army Environmental Hygiene Agency verified that known areas of radioactive contamination had been decontaminated to acceptable levels or were properly controlled. The ARCHS approved the SM-1 Post-Decommissioning Environmental Monitoring Plan, which has been used to provide on-going surveillance of the decommissioned facility.

In October 1996, the U.S. Army Center for Health Promotion and Preventive Medicine (USACHPPM) took extensive surveys of the SM-1 and surrounding environment to determine the radiological status of the facility at that time. In 2005, a Historical Site Assessment was developed using operational records and data collected from the 1996 USACHPPM Surveys. In 2009/2010 Characterization Surveys were completed and the Report was finalized in 2013.

The Historical Site Assessment and Characterization Surveys support the decommissioning study process outlined in Army Regulation 50-7. This process is performed by USACE, at the direction of the Army Reactor Office, to better define disposal activity costs.

The decommissioning strategy that was developed in the 1970's recommended that the deactivated reactors be placed into a safe storage mode that would allow the shorter-lived radionuclides to decay. It was expected that delaying decommissioning would reduce radioactive waste volumes and worker exposures. However, subsequent studies indicated that the levels of contamination present within the reactors would not be reduced by decay sufficiently to allow for release of the facilities without significant decontamination being performed. Additionally, concern regarding the increasing cost and decreasing availability of radioactive waste disposal led the Army Reactor Office (ARO) to recommend that an assessment be performed of the SM-1 reactor. The assessment allowed for a more accurate decommissioning cost estimate, which addresses projected changes in disposal options.

USACE developed a management plan for conducting an All Hazards Assessment, which contained provisions for four phases of work to be performed. Phase I included a Historical Records Review and Disposal Alternatives Investigation. Phase II, included performing a characterization survey and decommissioning cost estimate. Phases III and IV deal with decommissioning planning, design, and execution.


SM-1 Walk-Through

Contact Information

To join our stakeholder list and receive email updates, send your info to

USACE SM-1 Field Office
10236 Burbeck Road
Fort Belvoir, VA 22060

Or if you have questions, please don't hesitate to reach out to us. 

Please direct any inquiries regarding contracting opportunities to Brian Richardson via email to


SM-1 Decommissioning Contract Awarded

August 2020 Update: The U.S. Army Corps of Engineers, Baltimore District, has awarded a $67.98 million contract to joint venture APTIM AECOM Decommissioning LLC of Alexandria for the decommissioning, dismantling and disposal of the deactivated SM-1 nuclear power plant. Full news release available here.