The former Meloche quarry has been in operation since 1999 and Matrec became the owner in 2016. Upon acquisition by Matrec, an action plan was developed to accelerate site closure and complete facility upgrades to address the odor problems. The implementation of the action plan required the authorization of the Ministère de l’Environnement et de la Lutte contre les changements climatiques du Québec (MELCC). Authorizations were delivered to Matrec at the end of June 2019 and the first stage of the closure works began in August 2019.

Restart of the final site closure work

With the arrival of spring, Matrec has restarted the work for the final closure of the Pierrefonds landfill site. The work planned for 2021 mainly includes the screening and spreading of the last layers of cover material on the landfill area which will be completely covered with an impermeable membrane, as well as the complete seeding of the site in order to allow the vegetation to grow.

All final closure work is expected to be completed by the end of September 2021.

The landfill area is now sealed.

Over the past 18 months, Matrec has invested more than $10 million to:

  • Seal the site with the installation of an impermeable membrane and different layers of cover material on the landfill area
  • Increase by 400% the capacity of the biogas collection and destruction system
  • Destroy biogas by installing a new flare
  • Manage rainwater by building a peripheral ditch and a retention basin

All of this new equipment has been in operation since last fall and is constantly monitored to meet government requirements.

The site is now fully sealed following the installation of the impermeable membrane and all biogas wells are operational. All the biogas is now captured and directed to the new flare for destruction.

In 2021, only the installation of the last layers of cover materials will remain on a specific section of the site. Minor landscaping work and final seeding of the site will be carried out during the summer.

Photos taken at the end of October 2020.

Tight controls after site closure

Regulations require landfill owners to closely monitor facilities for 30 years after the site is permanently closed. Matrec will therefore have to submit regular control reports to the MELCC. To this end, the company has created a multi-million dollar fund to monitor the site in the future.


Government authorities having identified the residual materials management industry as an essential service in the context of the pandemic, Matrec is able to carry out the work to close the Pierrefonds site. Rest assured that all measures are being taken to prevent the risk of spreading and to ensure the safety of workers and those who will have access to the site.

Questions and comments

If you have any questions or concerns regarding the work at the Pierrefonds site, please contact 514.696.4509 or write to