Coal Companies: Waterway Polluters Or Protectors?

Coal companies have a significant impact on waterways, with coal mines and power plants affecting lakes, rivers, streams, and drinking water supplies. The issue is not limited to air pollution, as coal's lifecycle—from mining to processing and burning—can impact local water supplies, sometimes with devastating effects. The contamination of nearby water sources by coal mining is a significant concern, as water containing heavy metals like arsenic, copper, and lead is released, causing acid mine drainage. Mountaintop removal, a practice observed in Appalachia, involves flattening mountains and dumping debris into valleys, altering stream composition and burying headwaters. Coal ash produced during burning contains toxic elements, and improper disposal methods, such as unlined ponds, can lead to leaks and groundwater contamination. Thermal pollution from coal plants also affects water temperatures, impacting aquatic life. These issues highlight the need for regulations and alternative energy sources to protect our waterways and public health.

Coal mining and mountaintop removal

Coal mining, and especially mountaintop removal, can have a devastating impact on waterways. Mountaintop removal is a form of surface coal mining that involves removing the top of a mountain or ridgeline to access coal seams. This process often requires the removal of up to 600 feet of elevation, which is accomplished using explosives and enormous earth-moving machines called draglines.

The mountaintop removal process has severe environmental and health consequences. First, the removal of vegetation and topsoil contributes to deforestation and the destruction of diverse ecosystems. The resulting debris is typically dumped into nearby valleys, burying and polluting headwater streams. This practice has already buried more than 2,000 miles of streams and contaminated many more, with toxins from mining washing downstream and killing wildlife. The pollution also poses risks to human health, with increased levels of particulate matter in the air and the contamination of drinking water sources.

The coal extraction process itself can contaminate nearby waterways. Coal mining often releases highly acidic water containing heavy metals such as arsenic, copper, and lead into nearby rivers, lakes, and aquifers. This process, known as acid mine drainage, occurs when iron sulfide is exposed to air and water, changing the pH of streams.

After coal is extracted, it undergoes chemical treatment, creating coal slurry, a mix of water, coal dust, and clay containing toxic heavy metals. The unstable storage of this sludge in open impoundments can lead to leaks and spills, causing significant environmental damage.

In summary, coal mining, and particularly mountaintop removal, has severe impacts on waterways. From the destruction of ecosystems and pollution of streams to the contamination of water sources, these practices pose significant environmental and health risks that require urgent attention and stricter regulation.

Acid mine drainage

> "No hard rock surface mines exist today that can demonstrate that acid mine drainage can be stopped once it occurs on a large scale."

Coal ash and waste storage

Coal ash is the second-largest stream of industrial waste generated in the US, with nearly 130 million tons produced per year. Coal ash is disposed of in over 310 active on-site landfills and 735 active on-site surface impoundments. These impoundments are large facilities, averaging over 50 acres in size and 20 feet deep.

There is often a lack of oversight by federal and state governments when it comes to coal ash storage, and the existing minimal oversight does little to prevent the toxic components of coal ash from entering Americans' lungs or water supplies. The toxic substances contained in coal ash, such as arsenic, mercury, and lead, can make their way into nearby water tables. This can occur through groundwater contamination, where the toxins dissolve and slowly seep into the ground as "leachate" from landfills and lagoons, or through direct discharge into waterways. In 2012, 80% of all ash that wasn't "beneficially reused" was stored in onsite surface impoundments and landfills.

Wet storage of coal ash involves mixing the ash with water and storing it in large ponds or "lagoons." These wet disposal areas are called surface impoundments. Discharges from these impoundments can cause huge environmental damage, as seen in Belews Lake in North Carolina, where 19 out of 22 species of fish in the lake were killed.

Dry storage of coal ash in landfills also poses risks to groundwater, especially when the landfills are not properly lined. Stormwater can seep through the dry ash, collecting toxins as it percolates down into the water table. In addition, dry coal ash can be dispersed by wind and blown into neighbouring plots of land as "fugitive dust," which can be a major health concern when inhaled.

To address the risks associated with coal ash storage, the US Environmental Protection Agency (EPA) has established national rules for coal ash disposal and is strengthening existing controls on water discharges. These regulations include groundwater monitoring, liner requirements for new impoundments and landfills, groundwater cleanup, and the closure of unlined or failing impoundments.

Thermal pollution

Coal companies can indeed pollute waterways, and this contamination can occur during virtually every stage of coal's lifecycle, from mining to processing to burning.

"Once-through" coal plants pump water directly from a source, such as a river or lake, to heat up and create steam to turn turbines and generate electricity. The wastewater is then discharged back into the source, typically 20-25°F hotter than the water that receives it. This increase in temperature creates "thermal pollution," which can have several negative impacts on fish and other aquatic life. For example, it can decrease fertility and increase heart rates in fish. A typical once-through system can withdraw and discharge between 70 and 180 billion gallons of water per year.

"Wet-recirculating" plants avoid discharging wastewater by cooling and reusing it. However, these systems consume more water per year, upwards of 1.7 to 4 billion gallons.

As climate change raises temperatures, energy-water collisions may worsen. For instance, droughts may restrict water availability for coal plants, potentially forcing them to shut down. Additionally, hot weather can warm water sources to temperatures unsuitable for cooling, leading to reduced electricity production when energy demands are highest during hot days.

Mercury and other heavy metals

Mercury is a highly toxic heavy metal that is of particular concern due to its prevalence and the severity of its effects. Coal-fired power plants are the largest source of mercury emissions in the United States, accounting for about 41% of industrial releases. According to the Centers for Disease Control and Prevention, mercury exposure poses risks to both adults and children. Eight per cent of American women of childbearing age have unsafe levels of mercury in their blood, which can put newborns at risk of neurological deficits. Additionally, mercury exposure is linked to increased cardiovascular risk in adults. When deposited in water, microorganisms convert mercury into methylmercury, a highly toxic form that accumulates in fish and animals, interfering with their reproduction, growth, and behaviour, and even causing death.

Other heavy metals commonly found in coal ash and sludge include lead, nickel, tin, cadmium, antimony, and arsenic, as well as radioactive isotopes of thorium and strontium. These toxins are released into the environment during coal mining and burning and can contaminate groundwater, streams, rivers, and seas. Exposure to heavy metals can cause acute or chronic toxicity (poisoning) in humans and other organisms.

The effects of mercury and other heavy metal pollution from coal are wide-ranging and severe. They can impact aquatic life, human health, and the environment. In the case of the Dan River in North Carolina, a coal ash spill in 2014 released 39,000 tons of coal ash, contaminating the water and causing significant ecological damage. Similarly, in Tennessee, a spill of over 5 million cubic yards of coal ash into the Emory River resulted in one of the country's largest environmental disasters. These incidents highlight the dangers of coal ash and the importance of proper disposal and containment measures to prevent heavy metal contamination of waterways.

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