Recent Updates

SUMMER 2022

We are excited to release The Peninsula Harbour Area of Concern Status Report 2022 as it shows a great example of a collaborative efforts made by conservation authorities, municipalities, First Nation communities, Métis communities, environmental groups, industry and the public to develop and successfully implement the Remedial Action Plan (RAP) for the Peninsula Harbour Area of Concern (AOC). 

The purpose of this Status Report is to summarize the remedial and monitoring activities undertaken over the history of the Peninsula Harbour Remedial Action Plan, and to present an update on the status of beneficial use impairments (BUIs) within the Area of Concern. 

The Status Report discusses what study findings are indicating about the current state of the environment, and provides evidence that supports the recent re-designations to Not Impaired status of three of the four remaining beneficial use impairments (BUIs) in the AOC: Degradation of Fish and Wildlife Populations, Loss of Fish and Wildlife Habitat and Degradation of Benthos.

Table 1 below lists the original problems identified in the 1991 Stage 1 RAP report, their status in the subsequent Stage 2 RAP report (2012), and their current status as of 2022.

Overview of Issue

In 1987, the Canada-U.S. Great Lakes Water Quality Agreement identified 43 Areas of Concern (AOC) in the Great Lakes. Peninsula Harbour was one of the designated AOCs. This agreement commits both countries to “restore and maintain the chemical, physical, and biological integrity of the Waters of the Great Lakes.” 

Area of Concern (AOC) is the term used to identify those hotspots on the Great Lakes where the environment has been harmed to the point that it affects use and enjoyment of that area of the lake or may affect the health of the lake.

Peninsula Harbour is adjacent to the town of Marathon, Ontario, approximately 290 km east of Thunder Bay on the north shore of Lake Superior. The AOC includes the town of Marathon and is comprised of two regions: Peninsula Harbour to the north of Marathon and an area of Lake Superior extending 4 km out from Pebble Beach.

In 1991, Marathon community members came together to form a Public Advisory Committee, which assisted federal and provincial agencies in developing the first stage of the RAP for Peninsula Harbour (Stage 1 Report, 1991). This plan was developed to identify environmental problems and determine sources of pollution in the AOC

The harbour was identified as an AOC as a result of problems associated with:

• Bacterial contamination
• Aesthetic impairment
• Degraded fish and benthic communities
• High levels of toxic contamination, i.e. mercury and  polychlorinated biphenyls (PCBs) in fish and bottom sediments

There were 14 environmental issues, also known as Beneficial Use Impairments (BUIs), which were considered in each Area of Concern. BUIs are changes in chemical, physical and/or or biological properties that have impaired ecosystem benefits, or uses. A status summary for the Peninsula Harbour Area of Concern (1991-2010) follows:  

Summary of Peninsula Harbour BUIs: 1991-2010

Peninsula Harbour Progress Highlights

Below, you’ll find some major milestones for the Peninsula Harbour Area of Concern along the way:

1991: The Stage 1 Remedial Action Plan (RAP) Report for the Peninsula Harbour AOC identified 6 beneficial uses as “impaired”, 11 as “not impaired” and 2 as “requiring further assessment” (see the table Summary of Peninsula Harbour BUIs: 1991-2010 above).

Environment Canada and the Ontario Ministry of the Environment have been working towards the goals identified in the Peninsula Harbour RAP. This has involved characterizing the extent of environmental risk from mercury and polychlorinated biphenyl (PCB) contamination of harbour sediments, as well as monitoring and assessing trends in fish and wildlife health in the AOC.

1995: Federal and Provincial Municipal Industrial Strategy for Abatement (MISA) regulations significantly improve effluent quality at the Marathon mill.

2008: The Environmental Risk Assessment for Peninsula Harbour prepared and released by Environ Inc. outlines risks associated with contaminated harbour sediment. It includes both an ecological risk assessment (ERA) focused on risks posed to fish and wildlife and a screening level human health risk assessment (HHRA) focused on risks posed to people who eat fish caught in Peninsula Harbour. 

2008: Following a series of meetings with stakeholders in Marathon and Pic River, thin-layer capping is selected as the most suitable choice for management of contaminated harbour sediment.

2012: The Stage 2 Remedial Action Plan (RAP) Report is completed. It outlines water use goals and actions to achieve these goals, as well as the remedial strategies for ecosystem restoration. The report identified 2 beneficial uses that remained “impaired” (Restrictions on Fish Consumption and the Degradation of Benthos) and 2 requiring further assessment (Degradation of Fish and Wildlife Populations and the Loss of Fish and Wildlife Habitat).

2012 (Spring to Fall): A major Sediment Remediation Project in Peninsula Harbour at Marathon, ON, was co-funded by the Governments of Canada and Ontario. A thin-layer cap of 15-20 centimetres of clean sand is placed on top of the most contaminated sediment in Jellicoe Cove (Cost: $ 7,300.000. Former pulp mill owners contributed $3.0M, Environment Canada – $2.7M, Province of Ontario – $1.6M).

2017: Jellicoe Cove Thin-Layer Cap Long-Term Monitoring Assessment was completed by Ontario Ministry of the Environment, Conservation, and Parks. This survey demonstrated that the thin-layer sediment cap is effective and met the goals and objectives of the remedial effort.

2022: The Peninsula Harbour Area of Concern Status Report summarizes the remedial and monitoring activities undertaken over the history of the Peninsula Harbour Remedial Action Plan, and presents an update on the status of beneficial use impairments (BUIs) within the Area of Concern. The Status Report provides evidence that supports the recent re-designations to Not Impaired status of three of the four remaining beneficial use impairments (BUIs) in the AOC: Degradation of Fish and Wildlife Populations, Loss of Fish and Wildlife Habitat and Degradation of Benthos.

Peninsula Harbour Sediment Remediation Project

Elevated levels of mercury and PCBs accumulated in the Jellicoe Cove portion of Peninsula Harbour adjacent to a former pulp mill. The source of harbour mercury was a chlor-alkali plant which at one time operated beside the pulp mill.  To create clean habitat for plants and animals and to accelerate natural recovery, Environment Canada and Ontario Ministry of the Environment put in place a project to cap this contaminated sediment with clean sand. The project was completed during the summer of 2012. The integrity of the cap and “re-colonization” of the area by bottom dwelling organisms, including plants, will be monitored for the next 20 years. The capping project is the last major action required to address environmental concerns in Peninsula Harbour.

Here you can find additional photos of the the first post-cap long-term monitoring (LTM) survey (2017) demonstrated that the thin-layer sediment cap is effective and met the goals and objectives of the remedial effort.

View presentation materials about the capping project:

• Presentation “The Use of Thin-Layer Cap to Manage Hg and PCB Contaminated Sediments in Jellicoe Cove, Peninsula Harbour, Ontario, Canada” (November 20, 2012) – Technical presentation by Kay Kim et. Al from the Environment Canada, Sediment Remediation Unit on the thin-layer capping project in Jellicoe Cove, Peninsula Harbour. The presentation covers the sediment studies, risk assessment, management options, cap design, implementation, and long-term monitoring of the project.

• Presentation “Peninsula Harbour Area of Concern Thin-Layer Cap Long-Term Monitoring” (2021) created by Tara George, Ministry of the Environment, Conservation, and Parks, Great Lakes Unit.

View photos of the project taken during a public tour organized by the Peninsula Harbour Remedial Action Plan.

Peninsula Harbour – Important Documents

You can also access the full list of documents related to the Peninsula Harbour AOC in our DocumentCloud Hub.

Stage 1 Report (1991) – This is the Stage 1 Report for the Peninsula Harbour Area of Concern which identified the environmental conditions and defined the problem for future remediation work.

Environmental Risk Assessment (Environ 2008) – This environmental risk assessment for Peninsula Harbour includes both an ecological risk assessment (ERA) focused on risks posed to fish and wildlife and a screening level human health risk assessment (HHRA) focused on risks posed to people who eat fish caught in Peninsula Harbour. It also supports the development of a sediment management strategy for Peninsula Harbour. 

Community Open House Handout (June 2008)

Peninsula Harbour Fish Habitat Assessment (Northern Bioscience 2011) Existing fisheries and habitat reports, mapping, underwater video, and geospatial data were reviewed for the Peninsula Harbour Area of Concern on Lake Superior near Marathon, Ontario.  This review is to support an environmental assessment of proposed capping of mercury and PCB contaminated sediments in the Jellicoe Cove “hotspot”.

Peninsula Harbour – Factsheet (2011) Update from 2011 on the progress made and issues outstanding in the Peninsula Harbour Area of Concern

CEAA Screening (AECOM Jan. 2012) The proposed project to cover, or cap, the contaminated sediments in Jellicoe Cove in Peninsula Harbour was subject to an environmental assessment according to the Canadian Environmental Assessment Act (CEAA). This report was prepared by AECOM.

Water Quality Monitoring During Capping (AECOM Jan. 2012) Report by AECOM about the water quality monitoring during capping operations in Marathon, 2012.

Public Media Backgrounder (Jan.2012) Background information on the sediment capping project in the Peninsula Harbour Area of Concern.

Public News Release (2012) Quick facts about the capping project at the Peninsula Harbour Area of Concern

Stage 2 Report (Nov.2012) The Stage 2 Report for the Peninsula Harbour Area of Concern laid out the remedial strategies for Ecosystem Restoration

Peninsula Harbour – Factsheet_Newsletter (2014) An update on the Peninsula Harbour Area of Concern including the completion of the sediment capping project and the next steps

Update on Cap Monitoring (Environment Canada 2014) An update on the monitoring results from the Peninsula Harbour Area of Concern sediment management plan.

Jellicoe Cove Thin-Layer Cap Long-Term Monitoring (2017) (MECP, Nov 2019) The first post-cap Long Term Monitoring (LTM) survey demonstrating that the thin-layer sediment cap is effective and met the goals and objectives of the remedial effort. 

Peninsula Harbour Submerged Aquatic Vegetation and Cap Movement Study (2018) Results from the monitoring done in 2017 indicate that there has very little cap mobilization in the five years postcapping and a fine layer of silt has accumulated over the coarse and medium sand cap material in much of the cap, reducing the risk of contaminants being biologically active. 

Peninsula Harbour – BUI Summary Sheets (Nov 2020)

Peninsula Harbour AOC Status Report w Appendices (Nov 2020)

Final Peninsula Harbour Status Report – July 2022