Peninsula Harbour: Area of Concern
Peninsula Harbour was designated an Area of Concern (AOC) in 1987 under the Canada-U.S. Great Lakes Water Quality Agreement. Pollution from wastewater and contamination from logging and a former pulp mill led to degraded water quality and ecosystem health. Five out of the 14 beneficial use impairments (BUIs) were identified, which measure the environmental, human health and economic impact of poor water quality. An additional beneficial use was deemed “requiring further assessment”, meaning more information was required to determine whether it was impaired.
Accomplishments
All remedial actions were completed by 2012, and environmental monitoring and assessments have determined one remaining BUI.
Over the past 35 years, there has been significant progress in restoring the water and environmental quality in the AOC. This includes:
- improving municipal and industrial wastewater treatment through upgrades to the Town of Marathon’s wastewater treatment plant in 1982
- improvements to the local pulp mill in 1995 (closed in 2009) and the closure of a chemical plant in 1977, which was the primary source of mercury contamination
- the implementation of a thin-layer sediment cap in 2012 over the most contaminated sediment at Jellicoe Cove to create a healthy fish habitat, stop the spread of contaminated sediment and accelerate the natural recovery process by 75 years
- the restoration of fish habitat and diversity of mostly native species with only minor organic impurities leftover from logging activities prior to the 1980s
- the significant decline in polychlorinated biphenyls (PCBs) and mercury in fish
Restoration of beneficial uses
Over the last decade, significant progress has been made to improve environmental conditions in the AOC. These beneficial uses are no longer considered “impaired”:
- restrictions on dredging activities (2012)
- fish tumours or other deformities (2012)
- degradation of fish and wildlife populations (2021)
- loss of fish and wildlife habitat (2021)
- degradation of benthos (2022)
Work continues on the one remaining beneficial use:
- restrictions on fish and wildlife consumption – wildlife consumption is not impaired, and an assessment is being conducted on fish contaminants and consumption
Recent actions
The overall health of Peninsula Harbour has improved for fish habitat, fish populations and benthos.
Following the thin-layer cap project in 2012, results under the 20-year Long-Term Monitoring Plan show the cap is stable and has been effective in reducing contaminant concentrations. Results also show a healthy benthic community and vegetation, which are an indication of a healthy aquatic habitat.
Remaining actions
We will continue to work with local and provincial partners to support environmental monitoring and assessment studies needed to confirm the last beneficial use is restored. Priorities are to:
- assess the restrictions on fish and wildlife consumption, which includes results from a completed community fish consumption survey
- continue to implement the Long-Term Monitoring Plan for the thin-layer cap every five years until 2032
- engage local and Indigenous communities on the assessment of the fish and wildlife consumption BUI and confirm restoration of Peninsula Harbour AOC
Outlook
Peninsula Harbour has seen significant progress towards restoration since its designation as an AOC. Under the Canada-Ontario Agreement on Great Lakes Water Quality and Ecosystem Health, we work with the province of Ontario to continue making progress towards remediation, environmental recovery and the restoration of beneficial uses.
Partners
We partner with other levels of government, non-government groups, Indigenous communities and members of the public. This restoration work requires a large amount of scientific and technical expertise, local knowledge, hard work and the help of:
- Biigtigong Nishnaabeg
- EcoSuperior Environmental Programs
- Environment and Climate Change Canada
- Métis Nation of Ontario
- Ontario Ministry of the Environment, Conservation and Parks
- Ontario Ministry of Natural Resources
- Peninsula Harbour Remedial Action Plan Community Liaison Committee
- Town of Marathon