Prior to 2015, the Rio Tinto Alcan aluminum smelter in Kitimat, B.C. applied to modernize their facilities.
Following collaborative environmental assessments, it was concluded that the technological improvements would resultantly increase the smelter’s sulfur dioxide emissions.
This was predicted to pose a “moderate” level of risk to the ecosystems nearby.
Although the risk was labelled “moderate”, the B.C. government granted Rio Tinto permission to raise sulphur dioxide emission limits from 27 to 42 tonnes per day – as long as an extensive monitoring program of the Kitimat Valley was implemented.
Since then, there has been continuous monitoring of lakes, rivers, community health, vegetation and forest soils.
Justin Spak, a Trent University student in the ENLS M.Sc. program, is assessing the forest soil properties in Kitimat Valley.
As part of his research, he sampled soils from 2 pre-established plots near and far from the smelter within the Kitimat Valley.
The samples were bagged (pictured below) and brought back to Trent University to undergo laboratory analyses to quantify soil properties of interest, namely: pH, exchange acidity, organic matter, and nutrients/base cations such as exchangeable calcium, potassium, and magnesium.
Literature suggests that the decline in soil pH, decrease in organic matter, and loss of nutrients/base cations are all key indicators of soil acidification caused from sulphur dioxide emissions.
Justin was responsible for determining whether or not significant detectable change of these properties occurred between 2015 and 2018. This is a challenge because soil properties can be drastically different even when sampled in the same area – especially in old forest soils.
Justin’s research found small yet significant changes for a couple of soil properties.
However, these changes contradicted one another and did not collectively align with the soil acidification concept.
Measures put in place to monitor soils from Rio Tinto Alcan aluminum smelter emissions have been relatively effective shown by small changes – which is good news for surrounding ecosystems.
Justin’s project helps provide insight into how smelting technologies can be made cleaner to reduce their negative impacts the environment.
This is important when considering other industries, their potential environmental impacts, and the effectiveness of long-term monitoring plans.
The project is just one part of a successful collaboration between industry, the B.C. provincial government and various organizations like Trent University with the collective goal to monitor, identify and minimize any degrading environmental impacts over time.
We thank Justin for conducting important research that can help big industries, like the aluminum industry, reduce the impact on the environment in as many ways as possible.
“Trent University has allowed me to experience amazing research opportunities. I was fortunate to spend a week in Nanjing, China for a Fate Contaminants in the Environment summer school organized by the International Institute for Environmental Studies (IIES), to field sample in wild northwestern British Columbia for my project, and be part of a nomadic lake sampling squad on the stunning arctic terrain near Iqaluit, NU. I’m very appreciative of working alongside such a diverse group of people, for the advice and guidance from my supervisor Julian Aherne, committee members Jean-Francois Koprivnjak and Shaun Watmough, and for the numerous invaluable resources available for a student.”