Coal is a plentiful fuel source and relatively cheap to produce. It can also be converted to useful energy. However, coal production and use can harm the environment.
Coal mining has negative effects
The source of 64% of all coal mined in America in 2020 was surface mines, sometimes called strip mining. These operations are responsible for removing the soil and rocks above coal deposits or mines. Wyoming’s Powder River basin is home to the largest surface mines in America. There, coal deposits can be found close to the surface at up to 70 feet thick.
Large areas of the Appalachian Mountains have been affected by mountaintop removal and valley filling mining. This form of coal extraction involves removing the tops of mountains using explosives. This method alters the landscape and sometimes leaves streams covered in dirt and rock. Water from these valleys could contain pollutants that could harm downstream aquatic wildlife. Mountaintop mining has been used since the 1970s. However, it became more popular and controversial in the 1990s.
U.S. law requires that water and dust runoff from coal mined areas must be controlled and the area reclaimed near its original condition.
Underground mines have a smaller impact on the landscape than surface mines. Underground mines can cause the ground to collapse, and acidic water may drain from abandoned mines.
Underground mines can produce methane gas from coal deposits. Coalbed methane should be vented from mines to make mines safer. Based on global warming potential, methane from abandoned coal mines and coal mining accounted for about 8 percent of U.S. total methane emissions in 2019. Some mines can capture, use or sell coalbed methane from mines.
Emissions from coal-fired power plants
Coal combustion is responsible for several major emissions
- Sulfur dioxide (SO 2), which is responsible for acid rain and other respiratory diseases
- The respiratory diseases caused by smog include NOx (nitrogen oxides) and NOx (nitrogen dioxides).
- Particulates are responsible for smog, haze and respiratory diseases and lung disease.
- Carbon dioxide (CO 2), the primary greenhouse gas, is produced by burning fossil fuels like coal, oil and natural gas.
- Mercury and other heavy elements have been linked to neurological and developmental problems in humans and animals.
- Fly ash and Bottom Ash are the residues from coal-fired power plants.
Fly ash used to be released through smokestacks in the past. However, current laws require that pollution control devices capture most fly ash emissions. Fly ash and bottom Ash are typically stored near power plants in the United States. Environmental concerns include groundwater pollution from coal ash storage, landfills and large coal ash impoundments that have exploded.
Reduce the environmental impact of coal use
Industries are required to reduce the number of pollutants released into the atmosphere and water by The Clean Air Act and The Clean Water Act.
There are many ways that the coal industry can reduce sulfur and other impurities in coal. The industry has also discovered more efficient ways to clean coal after mined. Some coal consumers even use low-sulfur coal.
To remove sulfur from their smokestacks, power plants use flue gas desulfurization equipment (also known as scrubbers). The U.S. government and the coal industry have collaborated to create technologies that remove impurities or make coal more efficient. This reduces the amount that coal is burned per unit of energy.
Some types of coal can have mercury emissions reduced by equipment designed to reduce SO 2, NOx and particulate matter. Scientists are working to find new ways to reduce mercury emissions from coal-burning power stations.
There is research underway to reduce CO 2 emissions from coal combustion. One way to address CO2 emissions from coal combustion is the carbon trap. This method separates CO 2 from the emission sources and extracts it in concentrated streams. The CO 2 can then either be stored underground or sequestration.
Recycling and reusing can reduce the environmental impact of coal production. Reclaimed land used previously for coal mining can now be used to build airports, landfills and golf courses. The scrubbers can capture waste products and make cement and synthetic gypsum for wallboard.