Delineation and Soil Remediation at Hawkins Island Coast Guard Site, Lake Superior, Ontario

The Hawkins Island Minor Shore Light (MSL) (DFRP # 83486, FCSI No 00014403) is owned by the Government of Canada (Custodian: DFO). It is located at the southern tip of Hawkins Island on the north shore of Lake Superior next to the town of Marathon.

Previous environmental investigations at the site assessed for contaminants including metals and PCBs in the vicinity of the current MSL. Soil samples near the MSL from up to 0.18m below surface (bedrock depth) contained several metals in concentrations above applicable standards. In 2020, during a site visit, the Canadian Coast Guard (CCG) identified that elemental mercury was present in and on soils near the helipad that was constructed at the original location of the lighthouse. It is understood that the mercury originates from a mercury bath that would have been used for the lighthouse.

A review of historical documentation indicates that the helipad is located at approximately the same location as the former lighthouse. It is inferred that in addition to the presence of the mercury bath, the light was likely fueled by a petroleum product, and thus petroleum impacts may be present in the area.

The contamination requires assessment and remediation prior to replacement of the helipad, scheduled for summer 2021.

The work to be undertaken at the includes the following physical activities:


  • Remove visible mercury impacted soil from the area of the helipad using hand tools and store it inside sealed pails. These pails will be disposed of off-site at an approved waste facility. Limits of visible mercury (and thus limits of remediation work) will be determined via field screening with a portable mercury vapour meter.
  • Collect confirmatory soil samples surrounding the helipad following removal of the visible mercury impacted soil.
  • Collect additional soil samples in the helipad area to delineate other COPC criteria exceedances associated with both the helipad and the former lighthouse activities that occurred in this area.
  • If required, re-mobilize to the site to complete any additional soil delineation or remediation, based on the results of the confirmatory testing.


  • Collect and conduct laboratory analysis of soil samples surrounding the MSL tower to delineate impacts observed in the historical Phase II ESA.
  • Collect a paint sample from the MSL light tower structure for analysis of lead and mercury.


  • Conduct a visual survey within the federal site boundaries to determine the presence or absence of waste dumps and/or scattered debris and determine if the light tower battery is present at the site.
  • Take photos of the helipad area, the light tower area and any other areas of environmental importance (e.g., dump sites).


The work is anticipated to start in July 2021 and be completed by October 2022. 


Latest update

December 16, 2021 - The assessment decision statement has been issued to the proponent.



Fisheries and Oceans Canada
Chris Davis, Environmental Officer, Real Property, Safety and Security
520 Exmouth Street
Sarnia, Ontario
Telephone: 519-331-0870

  • Location

    • Hawkins Island (Ontario)
  • Nature of Activity

    • Waste Management
    • Remediation and conservation
    • Soil management
  • Assessment Status

  • Start Date

  • Proponent

    Fisheries and Oceans Canada
  • Authorities

    • Fisheries and Oceans Canada
  • Assessment Type

    Project on federal lands
  • Reference Number


This map is for illustrative purposes. The markers represent the approximate locations based on available data. More than one marker may be identified for a given assessment.


Nearby assessments

...within 200 kilometres
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