The US Department of Energy (DOE) Office of Environmental Management (EM) is set to decommission and demolish (D&D) a second submarine reactor prototype at the Idaho National Laboratory (INL) Site’s Naval Reactors Facility (NRF).
The Submarine 5th Generation General Electric (S5G) prototype, which has been defueled, is a land-based reactor vessel that served as an important training ground for Navy submariners.
A ceremony marking the transfer of the defueled S5G prototype from NRF to EM was held at NRF. Jeff Avery, EM Principal Deputy Assistant Secretary, attending the ceremony praised the efforts of EM crews in Idaho. Idaho Clean-up Project Manager Mark Brown said the EM team is excited to continue its close partnership with NRF.
“Our clean-up contractor, Idaho Environmental Coalition (IEC), has a well-trained and motivated workforce that has demonstrated huge progress in safely demolishing the first NRF submarine prototype, S1W,” Brown said. “This same workforce will maintain demolition momentum at the S5G prototype.”
D&D plans at S5G are consistent with a 2019 agreement between EM and the Office of Naval Reactors that created a path for EM’s current D&D efforts at the Submarine 1st Generation Westinghouse (S1W) and the Aircraft Carrier 1st Generation Westinghouse (A1W) legacy prototypes at NRF.
“S5G was a testbed for multiple technologies that are still used today, ensuring our submarine fleet can operate anywhere, anytime, virtually undetected,” said Gil Pratt, Naval Reactors Idaho Branch Office Manager. “Naval Reactors is preserving the legacy of S5G through oral histories, written records and artifacts from the prototype.”
The Submarine 5th Generation General Electric prototype was constructed in a below-ground basin, unlike the Submarine 1st Generation Westinghouse and Aircraft Carrier 1st Generation Westinghouse prototypes. The S5G prototype, constructed in 1965, was built to simulate the operations of a nuclear reactor within a submarine.
During operations, it was submerged in thousands of gallons of water to mimic ocean-like conditions. The prototype also was used to train nearly 12,000 naval officers and enlisted personnel to operate the propulsion plants of nuclear-powered submarines. The prototype was shut down in 1995 and its reactor vessel was defueled in 1999.
EM, with the agreement of the Environmental Protection Agency and the state of Idaho, has released an engineering evaluation and cost analysis on the final end state for D&D of the S5G prototype. D&D of the S5G prototype required an evaluation separate from the S1W and A1W prototypes because the S5G prototype was constructed below ground, unlike the other two.
Following the public comment period, a memorandum will be prepared to document the final end-state decision for the S5G prototype. Four alternatives are detailed in the evaluation and analysis. EM anticipates signing that memorandum next year.
