Coal Mining: Streams And Rivers Pollution Risk

Coal mining is a practice that has been associated with damaging effects on air and water. Coal mines and power plants heavily impact lakes, rivers, streams, and drinking water supplies. The process of mining and burning coal releases several pollutants, including toxic heavy metals like arsenic, copper, lead, cobalt, cadmium, silver, and zinc, which contaminate water bodies. The water draining from these mines often contains high levels of acidity and pollutants that can harm aquatic life and render water unusable. Additionally, the storage of coal waste and ash in unlined ponds or pits can result in leaks, further contaminating nearby waterways and drinking water sources. The environmental and health consequences of coal mining and its impact on water bodies have led to growing public concern and the need for stricter regulations.

Mountaintop removal mining

The MTR process begins with the removal of topsoil and vegetation from the mountaintop. Explosives are then used to blast away the rock and soil above the coal seams, and the debris is usually disposed of in the surrounding valleys, forming what is known as "valley fill" or "holler fill". This process can result in a loss of up to 600 feet in elevation and has been shown to alter the composition of nearby streams, impacting aquatic life and water quality.

The Environmental Protection Agency (EPA) has conducted research on the impacts of MTR on headwater streams and other water resources near mining sites. Their studies have found that MTR has altered the composition of nine out of ten streams in mining areas since 1992. Additionally, a 2012 study by the Environmental Science and Technology journal concluded that decades of MTR in Appalachia may have harmed aquatic life along more than 1,700 miles of streams in southern West Virginia.

The negative environmental and health impacts of MTR have led to calls for stricter regulations and reclamation efforts. While federal law requires reclamation of MTR sites, the focus has traditionally been on stabilizing rock formations and controlling erosion rather than on reforestation. In 2016, the Office of Surface Mining, Reclamation and Enforcement finalized the Stream Protection Rule to protect water quality and communities affected by MTR. However, this rule was repealed by President Trump in 2017.

Despite the negative consequences, MTR is sometimes considered the most cost-effective method of extracting coal, and it has been argued that it is safer for miners than traditional underground mining methods. MTR allows for the extraction of thin seams of coal that would be inaccessible through underground mining. However, the mechanization of MTR has also resulted in significant job losses in the coal industry.

Coal washing and waste storage

Coal washing is a standard practice in developed countries. It involves washing mined coal with water and chemicals to remove impurities before it is burned. This process generates wastewater, which is often stored in coal slurry impoundments or ponds. These ponds can leak, spill, or fail, leading to the contamination of nearby rivers and streams.

In 2000, a coal slurry impoundment in Kentucky failed, resulting in the release of over 300 million gallons of thick black sludge into nearby rivers and streams. This was 30 times larger than the Exxon-Valdez oil spill. Similarly, in 2014, 39,000 tons of coal ash spilled into North Carolina's Dan River. Six years earlier, more than 5 million cubic yards of coal ash spilled into Tennessee's Emory River, contaminating it and causing a train wreck.

Coal washing also produces coal ash, a grey powder-like substance left behind after coal is burned. Coal ash typically contains toxic elements such as arsenic, lead, and mercury. In the United States, coal-fired power plants produce over 100 million tons of coal ash and other waste products annually.

The disposal of coal ash has been a contentious issue. The U.S. Environmental Protection Agency (EPA) has proposed two options for regulating coal ash waste: listing it as a "special waste" or hazardous waste, or regulating it as a non-hazardous waste. The first option would require Treatment, Storage, and Disposal Facilities (TSDFs) to obtain permits and comply with land disposal restrictions. The second option would not require permits, and monitoring would be the responsibility of citizens rather than the federal government. However, critics argue that the EPA's plan does not adequately address the disposal of coal ash, particularly the phase-out of wet storage impoundments in favour of landfills.

The improper storage and disposal of coal waste can have severe environmental and health consequences. Coal ash ponds can leak toxic substances into nearby waterways and drinking water supplies, leading to increased risks of cancer, heart damage, reproductive problems, and neurological disorders. Additionally, the release of coal ash and sludge into rivers and streams can result in the death of aquatic life and the contamination of drinking water sources.

Acid mine drainage

Coal mining has a detrimental impact on all types of waterways, including rivers, streams, lakes, and drinking water supplies. Acid mine drainage (AMD) is a significant contributor to this issue. AMD refers to the outflow of acidic water from coal or metal mines, often abandoned ones where coal mining activities have exposed rocks containing sulphur-bearing minerals, such as pyrite. This process occurs when the sulphur-bearing minerals react with air and water to form sulphuric acid, which then washes into nearby rivers and streams. The resulting acid can dissolve harmful metals and metalloids, such as arsenic, copper, and lead, from the surrounding rock, leading to highly acidic water that contaminates these waterways.

AMD has severe and long-lasting impacts on the environment, including fish, animal, and plant life. It can alter the pH of nearby streams, making them as acidic as vinegar or battery acid, which is detrimental to aquatic ecosystems. The contamination can also reach drinking water supplies, posing risks to human health. Exposure to coal ash, for example, has been linked to an increased risk of cancer, heart damage, reproductive problems, and neurological disorders.

The Environmental Protection Agency (EPA) has found that contaminated valley fills from mountaintop removal mining have altered the composition of nine out of ten streams in mining areas since 1992. This type of mining involves flattening mountains to access coal seams, resulting in debris being disposed of in surrounding valleys. Additionally, coal sludge, or slurry, which is the liquid coal waste generated during the washing of coal, is often stored in impoundments near coal mines. However, leaks or spills from these impoundments can contaminate underground and surface waters, further exacerbating the problem of AMD.

AMD is a serious long-term environmental problem, and its impacts can persist indefinitely, even long after mining activities have ceased. This is due to the challenge of effectively treating AMD once it occurs on a large scale. Water treatment can be costly, and the financial burden often falls on the public if companies refuse to cover these expenses. As a result, waterways may remain polluted by AMD for hundreds or even thousands of years.

Heavy metal contamination

Coal mining has been proven to have a detrimental impact on waterways, including rivers, streams, lakes, and drinking water supplies. The public tends to associate coal with air pollution rather than water pollution, but the rock affects water bodies in the proximity of the place in which it is being mined.

One of the ways coal mining contaminates water bodies is through acid mine drainage, which is the outflow of acidic water from coal or metal mines, often abandoned ones where coal mining activities have exposed rocks containing the sulphur-bearing mineral pyrite. Pyrite reacts with air and water to form sulfuric acid, which can then leach metals from surrounding rocks, and these dissolved metals can travel downstream. This process occurs naturally and is referred to as acid rock drainage, but when enhanced by mining activities, it is known as acid mine drainage. Mining activities can increase the concentrations of heavy metals in water by crushing rock, digging tunnels, and exposing new horizons of sulfide-rich minerals to oxidizing agents and water.

Coal ash, a byproduct of coal burning, is another source of heavy metal contamination. Coal ash contains toxic elements such as arsenic, lead, and mercury, and when it is stored in unlined ponds or pits, these heavy metals can escape into nearby waterways and contaminate drinking water. In 2014, 39,000 tons of coal ash spilled into the Dan River in North Carolina, and six years earlier, more than 5 million cubic yards of coal ash spilled into Tennessee's Emory River, causing one of the country's largest environmental disasters. Exposure to coal ash has been linked to an increased risk of cancer, heart damage, reproductive problems, neurological disorders, and other serious health conditions.

The contamination of waterways by coal mining activities has had significant negative impacts on aquatic life and human health, and the remediation of these contaminated sites remains a challenge.

Water usage and depletion

Coal mines and power plants heavily impact lakes, rivers, streams, and drinking water supplies. Coal's lifecycle, from mining to processing to burning, can negatively affect local water supplies, with long-lasting and devastating effects.

The coal mining process brings acidic water carrying arsenic, copper, and lead to the surface, a phenomenon known as acid mine drainage (AMD). AMD occurs when iron sulfide is exposed to air and water, releasing sulphuric acid and dissolved iron. AMD can change the pH of nearby streams, making them acidic and unable to support fish communities. Mountaintop removal mining, practised in Appalachia, involves flattening mountains and disposing of debris in valleys, impacting waterways and aquatic life.

Coal washing and processing require significant water usage, contributing to water depletion. Coal-fired power plants use large amounts of water for cooling, impacting water availability for agriculture, drinking, and cooking. During droughts, water diversion to power plants exacerbates water scarcity.

The disposal of coal ash, a byproduct of coal burning, poses significant risks to water supplies. Coal ash contains toxic elements such as arsenic, lead, and mercury. It is often stored in unlined ponds or landfills, allowing heavy metals to escape into nearby waterways and contaminate drinking water. Coal ash spills have occurred in North Carolina, Tennessee, and other states, endangering aquatic life and posing health risks to humans.

The coal industry's heavy water usage and pollution contribute to water depletion and scarcity. Clean energy sources like solar and wind require significantly less water and are more environmentally sustainable.

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