Coal's Dark Side: Pollution And Its Causes

Coal is a major source of pollution and has extensive environmental and health impacts. Coal mining and coal-fired power plants contribute to air, water, and land pollution, affecting the health of miners, workers, and surrounding communities. The burning of coal releases toxic substances, including mercury, lead, sulfur dioxide, nitrogen oxides, particulates, and heavy metals, leading to respiratory illnesses, heart and lung diseases, neurological problems, and cancer. Coal mining practices, such as mountaintop removal, also cause landscape devastation and water contamination, resulting in the decline of wildlife and the contamination of downstream water sources. Additionally, coal is a significant contributor to greenhouse gas emissions, particularly carbon dioxide, which drives climate change and global warming, with consequences such as drought, sea-level rise, flooding, and extreme weather events.

Coal mining harms lands, waters, and wildlife

Coal mining has extensive environmental impacts, from devastated landscapes to polluted waterways. These issues reach far beyond greenhouse gas emissions, and often have irreversible effects on lands, waters, and wildlife.

Lands

Surface mining, a common method of coal extraction, involves removing large amounts of soil and rock to reach underground coal deposits. This process clears forests, strips away the earth, and leaves behind barren lands incapable of supporting wildlife. The removal of vegetation exposes the soil to precipitation, which can then carry away the topsoil, leading to erosion. Mountaintop removal is an especially destructive form of surface mining, where explosives are used to blast off the mountaintop, and the excess rock and soil are dumped into adjacent valleys, permanently burying headwater streams.

Waters

Mining operations can negatively impact water supplies, with long-lasting effects. Acid mine drainage (AMD) is a significant issue, where water reacts with sulfur-bearing minerals in rocks, resulting in highly acidic water containing toxic heavy metals. AMD renders waterways unusable for drinking and recreation, and poses severe threats to aquatic life and nearby communities. Additionally, coal plants discharge heated wastewater into nearby water sources, creating "thermal pollution" that can decrease fertility and increase heart rates in fish.

Wildlife

The degradation of land and water habitats through coal mining activities has severe consequences for wildlife. The loss of forests and streams disrupts ecosystems and forces wildlife to seek new homes. The pollutants emitted by coal-fired power plants, such as sulfur dioxide, nitrogen oxides, mercury, and arsenic, contribute to smog, acid rain, and toxic air pollution, impacting both wildlife and human health. The dust created by coal mining and processing causes respiratory issues and impairs the ability of leaves to photosynthesize, further harming wildlife.

Coal-fired power plants cause air pollution

Coal-fired power plants are a major source of air pollution, causing severe environmental and public health impacts. The burning of coal releases a range of airborne toxins and pollutants, including mercury, lead, sulfur dioxide, nitrogen oxides, particulates, and heavy metals. These emissions have been linked to various health issues, such as asthma, breathing difficulties, brain damage, heart problems, cancer, neurological disorders, and even premature death.

Sulfur dioxide (SO2), for example, is produced when the sulfur in coal reacts with oxygen. SO2 combines with other molecules in the atmosphere to form small, acidic particulates that can penetrate human lungs. It is a major contributor to asthma, bronchitis, smog, and acid rain, which damages crops, ecosystems, and acidifies lakes and streams. In 2014, US coal power plants emitted over 3.1 million tons of SO2.

Nitrogen oxides (NOx) are another significant pollutant emitted by coal-fired power plants. These gases are visible as smog and irritate lung tissue, worsen asthma, and increase susceptibility to respiratory diseases like pneumonia and influenza. US coal power plants released more than 1.5 million tons of NOx in 2014. Particulate matter, often referred to as "soot," is the ashy grey substance in coal smoke. It is linked to chronic bronchitis, aggravated asthma, cardiovascular issues, and premature death.

Mercury, a toxic heavy metal, is another concerning pollutant emitted by coal plants. Mercury can damage the nervous, digestive, and immune systems, and is particularly harmful to human health. Coal plants are responsible for 42 percent of US mercury emissions. Additionally, coal power plants release carbon monoxide, which can cause headaches and place additional stress on individuals with heart disease. They also emit volatile organic compounds (VOCs), which contribute to ozone formation, and arsenic, a potent carcinogen.

The environmental and health impacts of coal-fired power plants have led to increasing attention and regulation. The Clean Air Act and the Clean Water Act require industries to reduce pollutants released into the air and water. Efforts have been made to install pollution control technology, such as emissions scrubbers, to reduce emissions and improve air quality. These regulations and retirements of coal power plants have contributed to a decline in associated deaths. However, many plants still lack the necessary pollution controls, and the transition to cleaner energy sources is essential to mitigate coal's worst impacts.

Coal extraction techniques change the landscape

Coal extraction techniques have significantly altered landscapes, particularly through surface mining methods such as mountaintop removal and valley fill mining. This process involves removing the tops of mountains with explosives, changing the topography and impacting local ecosystems. Streams are sometimes buried under rock and dirt, and the resulting water drainage may contain pollutants harmful to aquatic life.

Surface mining, also known as open-cast, open-cut, or strip mining, involves removing layers of soil and rock above coal seams. This method can be completed quickly and with reduced risk to workers. However, it disrupts the land's aesthetic elements, creating unfamiliar configurations and exposing different colours and textures. The removal of vegetative cover, construction of haul roads, and stockpiling of topsoil contribute to increased dust, affecting air quality and harming nearby vegetation and human health.

Underground mining, on the other hand, uses technology like remote-controlled machinery and monitoring systems to access coal seams. While more complex, this method can help minimise exposure to hazardous conditions. One technique is room-and-pillar mining, where miners cut a network of rooms into the coal seam, leaving pillars of coal to support the roof. Another method is longwall mining, which uses hydraulically-powered self-advancing roof supports to temporarily hold up the roof while extracting coal.

The choice between surface and underground mining depends on the depth and thickness of the coal seam. Surface mining is often preferred when coal is closer to the surface, while underground mining is typically used for seams located deeper underground.

Regardless of the method, coal mining has been associated with significant negative environmental impacts, including habitat destruction, water pollution, and air quality degradation. These issues have led to coal being phased out in some parts of the global energy economy.

Coal ash storage can contaminate groundwater

Coal ash is the residue of burning coal. In the U.S., coal ash is generally stored near power plants, placed in landfills, or stored in unlined ponds. Coal ash contains toxic metals that can easily leach out and contaminate groundwater. Rain that falls on unlined coal-ash impoundments can transport these contaminants to underlying groundwater, affecting drinking water supplies.

According to a 2022 Earthjustice report, at least 24 coal ash sites in the U.S. have contaminated more than 100 private wells. Groundwater sampling at the New Castle plant between 2015 and 2017 revealed arsenic levels 372 times higher than EPA health standards and lithium levels 54 times higher than the proposed federal standard. The New Castle Generating Station, located an hour northwest of Pittsburgh, has been identified as one of the most contaminated coal-fired power plant sites in the country. The site retains 3 million tons of ash, which continues to leak high levels of contaminants into the groundwater, threatening the drinking water source for over 5 million people.

In 2019, a study found that groundwater near 52% of U.S. power plants with available data had unsafe levels of arsenic, and 60% had unsafe levels of lithium. These contaminants pose significant risks to human health, with arsenic being a known carcinogen and neurodevelopmental toxicant, and lithium associated with neurological effects.

The U.S. Environmental Protection Agency (EPA) has taken steps to address this issue. In 2023, the EPA announced actions to protect groundwater from coal ash contamination, including decisions on requests for extensions to the deadline for initiating the closure of unlined coal ash surface impoundments. The EPA also put several facilities on notice regarding their obligations to comply with regulations and laid out plans for future regulatory actions to ensure coal ash impoundments meet environmental and safety standards.

Despite these efforts, challenges remain. Many power plants storing toxic coal ash have not initiated cleanups or developed plans to address the contamination. Additionally, there are concerns about improper groundwater monitoring, insufficient cleanup information, and the regulation of inactive impoundments.

Burning coal releases airborne toxins and pollutants

Mercury, a toxic heavy metal, is released into the air when coal is burned. It has been linked to neurological issues, developmental problems, and damage to the digestive and immune systems. Mercury is particularly dangerous for children and can contaminate fish in lakes, making them unsafe to eat.

Sulfur dioxide and nitrogen oxide emissions contribute to the formation of acid rain, which has detrimental effects on the environment and infrastructure. Additionally, these emissions can cause respiratory illnesses, affecting the health of vulnerable individuals.

Particulates, or soot, are tiny airborne particles released during coal combustion. These particles can penetrate deep into the respiratory system, causing or aggravating respiratory conditions such as asthma and chronic bronchitis. They have also been associated with cardiovascular effects, including heart attacks and premature death.

Coal-fired power plants also emit other harmful substances, such as carbon monoxide, volatile organic compounds (VOCs), arsenic, and lead. These pollutants have a range of adverse effects on human health, including headaches, increased risk of cancer, and cardiovascular problems.

The release of these airborne toxins and pollutants from burning coal has serious consequences for both the environment and public health. It is important to reduce these emissions and mitigate their impacts to protect the well-being of communities and the planet.

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