Phase III Environmental Site Assessment and Environmental Monitoring of Remediation Work in Montreal

Phase III Environmental Site Assessment
Our firm was commissioned to conduct a Phase III Environmental Site Assessment and to prepare a technical specification for the remediation work, as well as to carry out environmental monitoring during the remediation of contaminated soils (Saint-Denis Street, Montreal). The project was undertaken in the context of rebuilding a structure with a change in site use, requiring environmental management as outlined in Article 31.53 of the Quebec Environment Quality Act (LQE), since the site previously hosted an activity listed in Schedule III of the Regulation respecting the protection and rehabilitation of contaminated land (RPRT): a gasoline distribution station (with three generations of fuel tanks) and a former mechanical maintenance and repair garage.

Services provided for this project included:

• Preparation of specific technical specifications;

• Management during the call for tenders;

• Project management and coordination;

• Environmental monitoring of the remediation work, including use of the Trace Québec platform;

• Sampling of soil (sidewalls and bottom of the excavation) and water, with preparation for laboratory analysis;

• Interpretation of analytical results;

• Preparation of a remediation report, certified by a qualified expert;

• Drafting of a summary report and decontamination notices;

• Preparation of a certificate of compliance with the environmental quality of the site (if required).

Environmental Monitoring of Remediation Work
Approximately 179.75 metric tonnes of contaminated soil were excavated, and the remaining soils were sampled from the excavation sidewalls and bottom. Contaminated soil was disposed of in accordance with the criteria of Schedule II of the Regulation respecting the protection and rehabilitation of contaminated land (RPRT) under the Ministry of the Environment, the Fight Against Climate Change, Wildlife and Parks (MELCCFP), and the Interim Soil Management Grid for Excavated Soils. Finally, annual monitoring of groundwater environmental quality was conducted from 2021 to 2023.