Impact of Tailings Seepage Water on Soil Quality and Vegetation

A long-term research program initiated in 1997 investigated how tailings water affects soil, water, and vegetation quality at Syncrude’s Southwest Sand Storage (SWSS) facility. Monitoring from 1997 to 2011 confirmed that seepage water led to elevated salinity, sodium, and chloride concentrations in groundwater and surface water which were particularly influenced by slope position. Technologies such as underdrain installation (2010) and soil capping strategies were evaluated to manage contaminant movement and water table levels. The study contributed data critical for designing reclamation systems that promote revegetation and environmental recovery.

The project found that seepage water led to salt and sodium accumulation in reclamation soils, particularly in areas where slope position affected water table depth and solute movement. Seasonal precipitation helped flush these elements from the root zone, maintaining soil drainage and structure. Despite elevated levels of certain ions in vegetation, plant health and vigor remained strong throughout the study. The findings support reclamation strategies that incorporate underdrain technology and are responsive to the topographic and hydrological influences across the facility.