Area of Environmental Concern (AEC) 10 is located adjacent to the foreshore of Watson Lake, YT, to the south of the Watson Lake Airport. AEC 10 was historically used as a refueling station during World War II, resulting in contamination of the soils by petroleum hydrocarbons and polycyclic aromatic hydrocarbons and the presence of petroleum hydrocarbons, polycyclic hydrocarbons, and metals in the groundwater on site.
The purpose of the project was to remove contaminated soils from the site to remediate the area and prevent further contaminant migration into Watson Lake. Impacted soils were removed by a wet-excavation method completed in 4-6 m wide sections, with crushed gravels for gravity shoring of the excavated slopes. Exposed groundwater remained in the open excavation throughout the project, and was maneuvered through the remediation area until the final backfill, where it was covered with clean materials.
Cascade Environmental Resource Group was retained by Franz Environmental Inc. on behalf of Public Works and Government Services Canada to monitor foreshore works associated with remediation of AEC 10.
Services provided by Cascade included monitoring water quality of Watson Lake during works, advising on spill prevention and response procedures and protocols, and providing adaptive management solutions for implementing effective site preparation and foreshore re-vegetation plans.