QM Environmental completed a remedial excavation of approximately 5,100 cubic meters of sediment from a pond where contaminated sediment had accumulated from Victoria International Airport runoff. The project area was located within a park owned by the Town of Sidney and the work was managed for Transport Canada, by Public Services and Procurement Canada. The project involved construction of a creek diversion to maintain a minimum flow for downstream fish, dewatering of the pond, excavation and offsite disposal of over 7,000 tonnes of PAH and metals contaminated sediment, construction of habitat features such as submerged planting beds, and large woody debris piles, removal of invasive species, and restoration of the upland disturbed areas.
The project was completed in a sensitive freshwater aquatic environment. Prior to excavation, a total of over 13,200 fish were salvaged and relocated, including cutthroat trout, threespine stickleback and pumpkinseed. The KEL,SET Creek and pond receives runoff from approximately ½ of the surface area of the Victoria International Airport, with base flow of 5L/sec, and large storm flows of up to 12,500L/sec. Management of these flows and contingency planning for storm events was critical to the success of the project, as it was completed up to a period of seasonally high rainfall.
Sediment excavated during the project was closely monitored by members of local First Nations employed under the W̱SÁNEĆ leadership council. The W̱SÁNEĆ was engaged by Transport Canada during the planning stages of the work and was present on-site throughout the execution. The sediment was transferred to a materials handling area in trucks, and then transferred to one of two permitted disposal facilities; one operated by QMF LP, and the other operated by the Cheam First Nation.
Site restoration included the construction of habitat features, including installation of 12 anchored large woody debris piles with root wads, placement of double washed round coho gravel, and construction of 4 submerged planting benches to create a diverse environment for the fish, birds and other local wildlife.
The project was completed on-time and on-budget. The local First Nations, neighbours, owner and contract manager was pleased with our work, our onsite staff and supervisors, management and our communication during the project.