Low Disturbance and Limited Access In-situ Soil and Groundwater

Following the recommendations of a Phase I ESA, an intensive Phase II ESA and contaminant delineation investigation program were conducted. The contaminated groundwater and gasoline from a fiberglass UST migrated east, towards the Athabasca River, and underneath an adjacent office building and community hall. Low-level (<1000 mg/L air) VOC fumes were identified inside the office building. In addition, during the Phase II ESA investigation, diesel contaminant was identified in the limited area southeast of the office building. Based on subsequent interviews and air photo reviews, a former forestry operation was detected and determined as a source of diesel contamination. An aggressive soil and groundwater in-situ bioremediation program was designed to prevent further migration of the contaminants towards the Athabasca River and to control the concentration of fugitive VOC inside the office building. In the first phase, the remediation program focused on the extraction of the estimated 35 m3 of the free gasoline on top of the shallow watertable. The ongoing soil and groundwater in-situ bioremediation program consists of two sets of horizontal air sparging (AS) and soil vapour extraction (SVE) wells installed underneath and east of the office building. The office building, general store, and community hall have been operating without interruption throughout the program execution