NorthStar Group Services has removed the Vallecitos boiling water reactor (VBWR) from the GEH Vallecitos Nuclear Centre in California and has delivered it for disposal to the Texas facility of its affiliate, Waste Control Specialists (WCS). The privately owned VBWR operated from 1957 to 1963 at the Vallecitos Nuclear Centre (VNC) in Alameda County some 48 km east of San Francisco. The VBWR was the first NPP to deliver significant quantities of electricity to a public utility grid and the first NPP to receive an operating licence issued by the Atomic Energy Commission (AEC).

Removal of the VBWR is part of ongoing work to rehabilitate the VNC site for commercial or industrial use. NorthStar agreed in May to take ownership of the site from GE Hitachi Nuclear Energy (GEH) for nuclear decontamination, decommissioning, and environmental site restoration. NorthStar and GEH are currently awaiting the regulatory approvals necessary to enable full transfer of the site and associated licence to NorthStar.

After more than a year of planning, the reactor vessel – nine feet in diameter, 22 feet tall and weighing more than 100,000 pounds -- was prepared for shipment and removed by NorthStar. The reactor was first loaded onto a highway transport system and then into a specially configured railcar at a rail transload facility for direct transfer by rail to WCS’s disposal facility in Texas where it will be safely disposed.

From 1965 to 1975, VNC undertook research for AEC’s nuclear energy programme and the civilian nuclear power industry. As well as the VBWR, the site hosted a Radioactive Materials Laboratory where post-irradiation examinations were carried outas well as a small 100kW Nuclear Test Reactor that used U-AL alloy fuel and was used for non-destructive material imaging. VNC also fabricated radioactive source materials for medicine and industry, under a California State licence. In May GEH announced cessation of all operations at the Centre and its intention to transfer the site to NorthStar for decommissioning.

The 5 MWe VBWR was a light-water moderated and cooled, enriched uranium reactor using stainless steel-clad, plate-type fuel. It was a pilot plant and test bed for fuel, core components, controls, and personnel training for Commonwealth Edison’s Dresden Nuclear Power Plant, which was built in Illinois five years later. The plant was originally collaboration between General Electric and Pacific Gas & Electric Company, with Bechtel Corporation serving as engineering contractor.

The VBWR plan was approved by General Electric’s management in late 1955. Construction began in June 1956 and the reactor went critical in 1957. The plant’s cost was well below the original estimate. It was built entirely with private funds. The entire privately owned VNC area is now managed by the US Department of Energy (DOE) Office of Legacy Management as a Manhattan Engineer District/Atomic Energy Commission Legacy Site.

After its closure, the VBWR was deactivated, defuelled, and put into SAFESTOR status pending eventual decommissioning. Waste removal from VNC began in September 2009 and was completed in 2010. Most of the nuclear waste generated from decontamination work was transuranic waste (TRU) that consisted of clothing, tools, rags, debris, and other items contaminated with small amounts of radioactive TRU elements. The TRU waste was packaged and shipped to the Waste Isolation Pilot Plant in Carlsbad, New Mexico, for permanent disposal. Decontamination and restoration activities are conducted in compliance with the requirements and licence provisions of NRC and the California Department of Health.

Image: Removal of the boiling water reactor from the GEH Vallecitos Nuclear Centre in California (courtesy of NorthStar)

Date: Friday, 17 November 2023
Original article: