A Conceptual Site Model (CSM) has been developed to assemble and synthesize existing information pertaining to contaminated sediment within the AOC. The overall deduction of the CSM is that that there is a low potential for adverse effects in benthic invertebrates, fish, wildlife, and humans that are exposed to contaminated sediment in the St. Marys River. Institutional controls to safeguard against exposing deeper, buried contaminants was advised.
A Sediment Management Strategy for the Canadian section of the St. Marys River Area of Concern (AOC) was drafted in 2021 to account for the updated Degradation of Benthos BUI delisting criteria. It provides a plain language summary of the history, current status, and future actions required as related to the management of contaminated sediment in the AOC. This strategy is intended to provide the AOC community with a clear understanding of the sediment assessment process and outline management approaches appropriate for the St. Marys River.
Over the course of more than two decades, five depositional areas where contaminants are present in sediments at high concentrations have been studied extensively. Summarized below are the current status and conclusions for Algoma Boat Slip, the Federal Water Lot, Bellevue Marine Park, East of Bellevue Marine Park and the Lake George Channel, Little Lake George and Lake George. Management approach, status, and further actions for the five areas are summarized below.
Algoma Boat Slip
- Management approach: Environmental dredging.
- Status: Verification sampling and assessment are underway to establish risk-based targets and to determine if dredging completed to date has met those targets.
- Future Actions: Depending on the results of the status assessment, either management is complete or further dredging and verification sampling are required.
St. Marys River Federal Water Lot
- Management approach: Monitored natural recovery, plus recommend administrative controls for in-water work.
- Status: Ongoing.
- Future actions: A recent round of long-term monitoring was completed in 2023, with continued monitoring every five years thereafter; adaptive management will be considered in the future if monitored natural recovery is deemed ineffective.
Bellevue Marine Park
- Management approach: No action required; recommend administrative controls for in-water work.
- Status: Complete.
- Future actions: None, other than abide by administrative controls for in-water work.
East of Bellevue Marine Park (Topsail Island Area)
- Management approach: No action required; recommend administrative controls for in-water work.
- Status: Complete.
- Future actions: None, other than abide by administrative controls for in-water work.
Lake George Channel, Little Lake George and Lake George
- Management approach: No action required, but administrative controls for in-water work within Lake George Channel recommended.
- Status: Complete.
- Future actions: None, other than abide by administrative controls for in-water work.
The Sediment Management Strategy is scheduled to be finalized in 2024 after public and indigenous engagement are complete. To view the draft Sediment Management Strategy, click here.