Project Summary

The work included winter spill response, site assessment, conceptual site model development, regulatory submissions and remediation of a 900L fuel heating oil spill at a residential site in Hay River, NT.

Remediation Activities

Initial spill response consisted of the excavation of impacted soils for local biotreatment, and the installation of a vertical groundwater recovery culvert into the deepest point of the excavation pending the removal of the mobile trailer. Following the demolition and removal of the mobile trailer, additional soil was excavated. Excavation was limited by the proximity of adjacent buildings and utilities, as well as the presence of saturated sands and gravels at the groundwater table.

Residual groundwater impacts included toluene and the petroleum hydrocarbon fractions F1 and F2. Groundwater was treated the following spring with the injection of a chemical oxidant slurry consisting of 800 kg sodium persulfate and 800 kg calcium peroxide. The groundwater monitoring wells were decommissioned one year after the in-situ chemical oxidation project was completed and regulatory closure was achieved.