Decommissioning of the Gentilly‑2 facilities

Dismantling of the water treatment plant and periodic inspection building at the Gentilly‑2 site

The Gentilly‑2 facilities include 17 buildings of different sizes. Two of the buildings are slated for dismantling in summer 2024: the water treatment plant (WTP) and periodic inspection building (PIB).

The WTP and PIB, which contain little to no radiological contamination, no longer serve a purpose in the context of the decommissioning of Gentilly‑2 and their fire-protection devices would required an update to meet current fire safety requirements. Early dismantling will enable our teams to focus their efforts on radiological, environmental and physical site monitoring.


  • Detailed characterization of buildings
  • Detailed decommissioning plan preparation
  • Plans and specifications
  • Dismantling of both buildings
  • Sampling and laboratory analyses


Can the dismantling activities present risks for the health of employees and the public?

The dismantling activities do not present any danger for the public, and every measure is taken to ensure the health and safety of workers.

Before personnel is mobilized, a characterization of the building is carried out to determine if there is any presence of contamination by radiological or hazardous material. We can thus plan for, among other things, any protection equipment that may be required for workers on the jobsite. However, the preliminary characterization of these buildings did not reveal any radiological contamination.

The dismantling of these buildings is essentially a demolition site, which is subject to strict health and safety measures, just like our construction sites. Even though this is primarily demolition work, the dismantling of buildings is overseen by resources specialized in radiation protection.

Where will the demolition debris go?

Hydro‑Québec has blanket contracts that make it possible to recover or recycle materials when possible (metal, for example). The debris that cannot be recovered or recycled will the transported to a location authorized by the Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs (MELCCFP).

Should the sampling and laboratory analyses reveal the presence of radioactive materials in certain debris, these will be safely stored in Gentilly‑2’s Solid Radioactive Waste Management Facility.

Are there other buildings that you are planning on dismantling in the short term?

We are currently assessing this possibility, but no decisions have been made at the present time.

It’s been 10 years since the closing of Gentilly‑2 nuclear power plant: Looking back and next steps

On December 28, 2012, after 29 years of safe operation, Gentilly‑2 nuclear power plant was permanently shut down and began its decommissioning process. Ten years later, some 40 employees continue to work on site to ensure the safety of the facilities, the health and safety of the population, radiation protection and environmental monitoring.

As we prepare for dormancy, our priorities for 2023 include carrying out radiological, environmental and physical monitoring in addition to managing the aging infrastructure.

Did you know? Since Gentilly‑2 nuclear power plant was put off-line, contracts totalling almost $30 million have been awarded to companies in the Mauricie and Centre-du-Québec regions.

Archeological surveys around the Gentilly‑2 facilities mandated by the Grand conseil de la Nation Waban‑Aki

On October 20, 2021, we opened our doors to a team of four archeologists mandated by the Ndakina office of W8banaki. Their goal? Carry out an archeological inventory and find traces of occupation by the W8banaki Nation along the Rivière Gentilly.

“Namasak,” the W8banaki place name for the head of the Rivière Gentilly, means “fish,” which leads us to believe that it may have been an important fishing area for the local W8banakiak prior to or during colonization, or even in more recent times.

We are pleased to have been able to collaborate in this great initiative.

Learn more about Waban-Aki culture.

To reach us

Info-Project line

1 866 388‑1978


Véronique Trépanier
Advisor – Community Relations