Located in the southwest corner of Hamilton Harbour, the Randle Reef site is approximately 60 hectares (120 football fields) in size. The site contains approximately 695,000 cubic metres of sediment contaminated with highly toxic polycyclic aromatic hydrocarbons (PAH) and heavy metals. PAH contamination at Randle Reef is a legacy of various past industrial processes dating back to the 1800s.

The Randle Reef sediment remediation project involves constructing an engineered containment facility (EFC) around and on top of a portion of the most contaminated sediment in the Harbour. The remaining contaminated sediment surrounding the ECF is currently being dredged (suctioned out) and placed inside the structure. The ECF was constructed with double steel sheet pile walls to fortify the structure and to prevent toxins from leaching out into the Harbour.

Environment and Climate Change Canada, the Ontario Ministry of Environment, Conservation and Parks, the City of Hamilton, the Hamilton Oshawa Port Authority, Stelco, the City of Burlington, and the Regional Municipality of Halton are all working together on the Randle Reef sediment remediation project.

The Government of Canada: $46.3 million
The Province of Ontario: $46.3 million
The City of Hamilton: $14 million
Stelco: $14 million
Hamilton Oshawa Port Authority: $14 million
The City of Burlington: $2.3 million
Halton Region: $2 million
Total Project Budget: $138.9 million

Environment and Climate Change Canada is the lead agency on the Randle Reef project, while contracts are being managed by Public Services and Procurement Canada.

Stage 1 started in 2015 with the re-construction of adjacent Pier 15. This was necessary to permit dredging of the contaminated sediment in the vicinity of Randle Reef. This was followed in 2016 through 2017 by the construction of an engineered containment facility (ECF) – the “steel box” – on top of the most highly contaminated sediment. Stage 2 involves dredging as much as 550,000 cubic metres of contaminated sediment and placing it within the ECF. Stage 2 began in 2018 and is expected to be completed in 2021. Stage 3 will involve placing an environmental cap on the ECF to isolate the contaminants. Once Stage 3 is completed in 2023, the ECF will be handed over to the Hamilton Oshawa Port Authority for use as a port facility.

Stage 2 is expected to be completed by the fall of 2021. Stage 2 timelines have been extended due to delays experienced by the contractor with the delivery of the dredge in 2018, record-high water levels across the Great Lakes in 2019, and workplace limitations related to COVID-19 in 2020. Timelines have also been extended because two factors have allowed for more contaminated sediment to be dredged and contained than was initially expected: the consolidation rate of contaminated material in the ECF has been higher than expected, and contaminated sediment in some dredge areas did not extend as deep as originally estimated and therefore the ECF can hold more contaminated sediment than was originally planned.

Stage 3 is expected to start in the spring of 2022.

The project will involve the use of a completely sealed engineered containment facility (ECF) to isolate the contaminated sediment from the surrounding ecosystem. While other confined disposal facilities for contaminated sediment exist in Canada, those facilities are not designed to contain contaminants with concentrations as high as those found at Randle Reef, nor are they designed to completely seal the contamination from the surrounding ecosystem. The Randle Reef ECF will be utilized as a port facility once it is filled with contaminated sediment and capped with a solid surface. This approach to managing contaminated sediment in an engineered structure and creating a port facility is a first in Canada.

The contamination of sediment at Randle Reef is the result of multiple historical sources over a period of more than 150 years, including coal gasification, petroleum refining, steel making and associated coking, municipal waste, sewage effluent and overland drainage.

Polycyclic Aromatic Hydrocarbons (PAHs) are a class of organic compounds that are present in oil, coal and tar and are produced during the burning of these fuels. PAHs are also formed by the process of incomplete combustion of such products as wood tobacco smoke and diesel fuel. There are several known PAH carcinogens (directly involved in causing cancer) and several others are suspected carcinogens.

Real-time environmental monitoring systems are being used to measure air and water quality in the vicinity of construction at each stage. Air and water quality criteria have been established to ensure that human health and the environment are protected. In addition, a water treatment plant is being used to treat all water displaced from the containment facility during Stage 2 and 3.

The completion of the Randle Reef engineered containment facility (ECF) in 2023 will be one of the most significant milestones in the restoration of Hamilton Harbour and its eventual delisting as a Great Lakes Area of Concern. Delisting of Hamilton Harbour cannot occur until remediation of contaminated sediment at Randle Reef has been successfully addressed, and the Randle Reef ECF is the signature Remedial Action Plan project to address the issue of legacy contaminated sediment. Unrelated goals such as restoring shoreline and wetland habitat and improving water quality through phosphorus reductions are also significant, however, and ongoing RAP projects to address those issues must also be successful before delisting is achieved.