WATERFRONToronto

Contaminated Soil Management

Aerial view of dig site

The revitalization of Toronto's waterfront is one of the largest urban brownfield remediation projects in the world. Given the contamination after decades of infilling and industrial activity, we anticipate managing approximately 2,000,000 cubic metres of contaminated soil over the next 20 years. Soils throughout the waterfront must be restored before the area can be developed into sustainable mixed-use communities.

The total area being revitalized by Waterfront Toronto is 800 hectares. The following pie chart shows the status of contaminated soil management for active projects only, meaning lands where some level of work is currently being undertaken. Projects Not Yet Started represent projects where contaminated soil management activities have not yet been undertaken, but some level of work is underway, such as planning or design.

Contaminated Soil Management

View a detailed map.

Soil Recycling

Contaminated soil is typically trucked to a landfill site and then clean soil is brought in to replace it; a process called dig and dump. To minimize this unsustainable practice, Waterfront Toronto established a pilot soil recycling facility in the Port Lands in July 2010. The pilot was an opportunity to treat soil on-site to an environmental condition that allows for its reuse. This process transforms a liability into a resource and minimizes the additional environmental impacts associated with moving the soil.

The objective of the pilot was to identify treatment options, assess economic feasibility, confirm that impacted soil could be treated and reused in compliance with Ministry of the Environment and Climate Change guidelines, and showcase treatment technologies.

Deme Environmental Contractors and Tetra Tech Canada Construction were chosen to conduct the pilot. Both operators treated contaminated soils from various Waterfront Toronto sites using soil washing processes, complemented by field trials of a number of advanced technologies. Approximately 20,000 cubic metres of soil was processed during the three month pilot processing period.

In addition to the field tests, the Ontario Centre for Environmental Technology Advancement (now called BLOOM) was retained to compare and quantify the environmental and societal impacts of the dig and dump approach versus the soil recycling option. The study results showed that the impacts of the dig and dump approach are significantly higher than the impacts of recycling and reusing soil.

The study also found that soil recycling and reuse creates societal, environmental, and health benefits by saving landfill space and aggregate quarry resources, reducing traffic accidents, noise, congestion, pavement wear and tear, truck traffic and fuel consumption. BLOOM quantified these benefits at $18.5/tonne, projected as $65 million over 10 years of avoided costs to the public. It was also estimated that soil recycling and reuse would reduce greenhouse gas emissions by 36 kg/tonne largely as a result of decreasing truck traffic..

Upon completion of the pilot project, Waterfront Toronto supported the establishment of a private operator to run a facility on the pilot site.

ApproachCost Estimate
Recycling Facility$40-50 / tonne
Dig and Dump$45-50 / tonne
Environmental and Social Cost Savings$18.5 / tonne
Dig and Dump, considering environmental and social costs$63.5-68.5 / tonne
Projected environmental and social cost savings to Waterfront Toronto by using the recycling facility over 10 years$65 million