In a recent post here on The WMEAC Blog, we wrote about the presence of microplastic beads in the Great Lakes. These beads are attributed to personal hygiene products, as outlined in a groundbreaking study published in Marine Pollution Bulletin. Here at WMEAC, however, we were struck by an additional finding within research—coal fly ash.
The research team initially misidentified fly ash particles as microplastic, because of its similarly round shape. However, upon closer examination using a scanning electron microscope (SEM), the research team discovered that 20% of the particles found in their samples were, in fact, fly ash.
Fly ash is a product of coal combustion that the EPA describes as similar in texture to talcum powder. Millions of tons are produced each year, some of which is reused in applications such as concrete, cement, and asphalt. However, Clean Water Action reports that two to five percent of coal ash is released into the atmosphere annually, resulting in millions of tons entering the water cycle each year (Check out the comprehensive report on fly ash here.).
Fly ash is not a benign substance. According to the EPA, fly ash can contain toxic substances like mercury, lead, vanadium, selenium, and arsenic. Fly ash that does not escape through a coal-fired power plant’s exhaust can also enter the watershed if it’s stored inadequately. In February, a broken pipe released 82,000 tons of ash into a North Carolina river; the ash contained arsenic levels 14 times higher than considered safe for human contact.
Eight of the 21 surface water samples examined by the Great Lakes study contained aluminum silicate, a component of coal ash. While this was not the chief objective of the study aimed at microplastics, the substantial presence of coal ash warrants additional questions. Just how much coal ash is in the Great Lakes? Were is it present and how does it move? We have some ideas of how the asharrives in the great lakes, and that we still contributing to the problem; but what impact does it have on human and environmental health? Can those impacts be mitigated and what are the options are for remediation?