The US Army Corps of Engineers (USACE) is set to begin decommissioning the SM-1A mothballed nuclear power reactor at Fort Greely, in Alaska, beginning next year, a project that is expected to take approximately six years, the American Nuclear Society reported on 2 July. USACE said it expects to release a request for proposals soliciting contractor bids for the decommissioning and dismantlement project by late summer.

The USACE issued a final environmental assessment and finding of no significant impact for the SMA-1 decommissioning on 28 June, beginning a 30-day wait period before the plan is officially finalised. A public review period was held in February and March, and comments received during that time are addressed in the final documents. USACE intends to decommission the deactivated plant site to a level that will allow it to be released for unrestricted use.

The construction of SM-1A began in 1958 and first criticality was achieved in March 1962. The design was based on the concept of the SM-1 reactor at Fort Belvoir, in Virginia, a prototype for stationary medium-power plants (SM). The “1A” notation designates it as the first field plant of its type.

A 20.2-MWt pressurised water reactor, SM-1A was designed to be used as an “in-service” test facility for nuclear power in an Arctic environment, with its primary mission being to supply electrical power and heating steam to Fort Greely. The secondary mission was to study the economics of operating a nuclear power plant in a remote area where conventional fuel costs are high and supply lines unusually long.

By 1968, however, the decision was made to close the plant because of the high operating costs and the projected cost of replacing SM-1A’s reactor pressure vessel. The final shutdown was performed on the SM-1A Reactor in March 1972, in accordance with theSM-1A Decommissioning 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 pre-packaged radioactive waste, encasing certain reactor components (vapor container, waste tanks, and demineraliser room), sealing the pressure vessel, and installing appropriate warning signs and monitoring devices. Certain areas were maintained as restricted areas for radiation safety considerations. This method of decommissioning was selected due to the low initial cost and low personnel radiation exposure. Future remediation was to take place at a time when radiation levels and quantities of radioactive waste were significantly reduced due to radioactive decay. The plant put in safe storage (SAFSTOR) condition.

Because of SM-1A’s historical significance (the plant was found eligible for listing in the National Register of Historic Places), and because decommissioning will adversely affect the property, USACE signed a memorandum of agreement with the Alaska State Historic Preservation Office and the City of Delta Junction outlining how the history of SM-1A and its unique artic mission will be preserved.

USACE said that “when safe and feasible,” it will salvage historical items from the reactor facility. This includes informational safety plaques and an unopened time capsule. Also, within two years of awarding the decommissioning contract, USACE will develop a detailed plan for the identification, curation, storage, and transportation of SM-1A’s historical items.

The project team continues to make advances towards a Request for Proposal (RFP) for the procurement process for the decommissioning and dismantlement of the SM-1A. The team anticipates the release of the RFP by late summer. The USACE team is also working with Defense Logistics Agency, Fort Greely staff, and Doyon Utilities to implement the separation of utilities between the north and south end of Building 606 which houses the SM-1A reactor. This portion of the project must be implemented prior to decommissioning activities to ensure the USACE team can safely execute the project.

The USACE team plans to continue to work on the decommissioning planning efforts and receive a Decommissioning Permit from the Army Reactor Office (ARO) in early 2022 for the site.In 2022, the USACE team will continue to work with Doyon Utilities to complete the segregation work at the site. Additionally, the team plans to award a contract for the implementation of decommissioning. Decommissioning efforts will start in early FY 2023. In FY 2023 – FY28 the USACE team will be implementing the various phases of the decommissioning efforts at the site.