Coal ash, also known as coal combustion residuals (CCRs), is the particulate residue that remains from burning coal. Depending on the chemical composition of the coal burned, this residue may contain toxic substances and pose a health risk to workers in coal-fired power plants.
2 Occupational health concerns
3 Health effects of toxic constituents found in coal ash
4 Coal ash reuse
5 Coal ash waste regulations
Coal ash is found in coal-fired power plants. Coal is burned in coal-fired plants to produce electricity. More specifically, the coal is pulverized and then burned to generate energy. The particles that remain after burning coal is called coal ash. The production of coal combustion produces many by-products of coal ash. Some of these by-products are boiler slag, flue gas desulfurization material, bottom ash, fly ash, scrubber residues, cenospheres and fluidized bed combustion ash. Depending on the coal that was burned, the chemical composition found in coal ash can vary. However, most coal ash will contain aluminum oxide (Al2O3), calcium oxide (CaO) and silicon dioxide (SiO2). Regardless of the by-product produced, there are many toxic substances that are present in coal ash that can cause major health problems in humans. Some toxic constituents that are found in coal ash are arsenic, boron, cadmium, chromium, cobalt, copper, lead, mercury, molybdenum, selenium, thallium and uranium.
In the United States, approximately 44.6 percent of electricity is produced from over 450 coal-fired power plants. In 2012, approximately 110 million tons of coal ash was produced from the coal that was burned in the United States. However, more than half of the coal ash produced is dumped into surface impoundments (wet storage) or landfills (dry storage). Specifically, there are approximately 1,070 coal ash waste ponds and about 435 landfill sites located throughout the United States. The major problem of these disposal sites is the toxicity of coal ash escaping and causing harm to humans and the environment. When coal ash waste is not properly controlled, the toxic substances can affect drinking water, food and air.
Occupational health concerns
Coal ash contains many toxic substances that can negatively impact the human body. Employees working in coal-fired power plants or near coal ash waste sites are at major risk of inhaling coal ash dust. Coal a