Posted By: epstudios

By Ella Swan, Lake Windermere Ambassadors’ Summer Student

Coal Dust and Our Lake

Like in many other BC towns, Invermere has a Canada Pacific Rail (CPR) line running through. CPR is not required to disclose the cargo they are transporting to the public (only to the municipalities), but as can be seen from the open rail cars, coal is commonly shipped through our town. The fact that the cars are open to the air begs the question of how much coal dust might be blowing out of the cars, and into the air and water. The train runs right along the shore of Lake Windermere, so anything that blows out of the cars could get in to the whole lake. This article explores what we know and what we don’t know about the impacts of coal dust on lake ecosystems.

Coal dust has been shown to negatively affect aquatic ecosystems in some instances. Most of the documented impacts have been physical effects.  These include the actual particles in the water which cloud the water and reduce the amount of light that can reach the bottom. This causes plants to not be able to photosynthesize, producing less oxygen for the fish and other organisms. In extreme cases, the increased cloudiness has been shown to alter the freshwater ecosystem. Coal dust in aquatic environments has also been shown to smother, abrade, and clog breathing and feeding organs in fish (Ahrens and Morrisey, 2005). Data have been available about these impacts for a long time. As early as the 1930s, a study was released that linked fish mortality in freshwater streams to irritation caused by coal dust (Pautzke, 1938).  A 1979 study reported that the spawning success of fathead minnows was reduced from 90% to 36% because of PAH (polycyclic aromatic hydrocarbon) contamination from coal. (United States Environmental Protection Agency, 1979).

What impacts might coal dust have on water quality? The Navajo have traditionally believed that coal is the liver of the earth, a belief that is actually backed up by science. When left in the ground coal acts as a filter. As water percolates though it, coal seams trap heavy metals and toxins and actually improves water quality. However when the coal is mined, shipped, and burned, these metals and toxins are allowed to escape into the environment.

In the mining process, the impacts on water quality vary based on method. In the Powder Basin in Montana, strip mining is used, a technique that is so destructive it can alter watersheds. What this means is that land that once had a natural flow and retention of water ends up permanently disfigured. Any nearby stream or river is at a high risk for being polluted with excess sediment from disturbed topsoil. This can cause fish and plant death and even flooding. Chemical contamination of groundwater is another risk that this type of mining opens land up to.

Burning coal produces the most impact worldwide. Aside from liberating very nasty heavy metals such as uranium and thorium, the chemical smoke collects in the troposphere (the closest layer of atmosphere to earth) and goes through a series of chemical reactions with oxygen and water that can produce acid rain as well as generally degrade air quality and warm the earth (Formation of Acid Rain, John Ha).

The shipping of the coal is a more direct concern for Invermere. Coal dust can get into water when it is loaded, unloaded and during transport. Because of the way that trains carry coal, large amounts of coal dust can simply blow out of the cars. As in Invermere, trains always carry coal in open cars, allowing the potential for dust to escape. In 2009, a BNSF Rail representative testified that over a 400-mile journey, approximately 645 pounds of coal dust per car are lost. With an average of 125 cars in a train, that’s 80,645 pounds of coal dust on one trip – that’s 200 pounds per mile per train. To reduce the amount of coal dust released into the atmosphere, a spray-on substance called a surfactant is applied to the trains before they leave. BNSF Rail (a company that operates mainly in the US and BC) claims that the use of surfactants reduces escaping coal dust by up to 85%. Assuming that is correct, 15% of 80,645 pounds is still 12,094 pounds of coal that is being released into the environment. And that’s just one train. An average of 20 trains pass through Invermere each day.

Coal dust can be dangerous for more reasons than one. Aside from any environmental concerns, the dust can cause derailments and even destabilization of the tracks. According to the Federal Railroad Administration, “coal dust travels from rail cars and blocks drainage pathways, reducing ballast’s drainage capabilities; this weakens the load carrying capacity of the ballast. The track may then become prone to shift when a train passes.”

Even though studies on this topic began early in the last century, relatively little research has been done on the environmental impacts of coal dust.   Accurate information on the regulations around controlling the dust can be difficult to locate. It’s up to us to push for the best possible regulations and research to keep our Lake this beautiful for generations to come.