Gentilly-1 (G1) is a permanently shut down and partially decommissioned, prototype 250 megawatt (MWe) CANDU® boiling water reactor in Bécancour, Quebec.
The reactor was put into service in 1972 and operated intermittently, for a total of 183 effective full power days, until 1978 when it was determined that certain modifications and considerable repairs would be required to continue operations. In 1984 it was permanently shut down and initial decommissioning was completed. Since then it has been in a safe, partially decommissioned, state of “storage with surveillance”.
The G1 Facility is owned by Atomic Energy of Canada Limited (AECL), a federal Crown corporation. G1, as well as another reactor, Gentilly-2 (G2), owned by Hydro Quebec, are located on the Gentilly Nuclear Generating Station site, which is also owned by Hydro Quebec.
The small G1 site is surrounded by the wider Gentilly Nuclear Generating Station site.
CNL has the responsibility to manage all of AECL’s sites and assets through a government-owned, contractor-operated (GoCo) model.