Coal Pollutants and Water
The United States has been mining coal for hundreds of years. Today, 45 percent of our electricity still comes from coal-fired plants, according to the U.S. Energy Information Administration. The seemingly inexhaustible supply of this carbon-based fuel comes at a heavy environmental cost. The resulting air, water and soil pollution has a serious impact on human health as well. Beyond currently-operating coal production, abandoned mines also pollute water. It is estimated that Pennsylvania has 2,400 miles of streams still being polluted from closed mines.
Types of Coal Mining
Coal can be extracted in two basic ways. Deep extraction requires digging shafts far underground that follow seams of coal underground. Strip mining involves clearing huge tracts of land of vegetation and stripping the top layer of coal from the earth’s surface. Strip mining is by far the most damaging in terms of coal pollutants. Destruction of trees and vegetation on entire mountaintops causes erosion and landslides as well as water pollution.
The slag produced by the unprofitable part of strip-mined soil contains large amounts of toxic metals. When coal is extracted from the profitable strip-mined soil, great amounts of fresh water are used in the process. What’s left over is called sludge, and it is even more toxic than slag. High concentrations of mercury, arsenic, lead and selenium may be found in sludge, according to the Environmental Protection Agency.
Water and Air Pollution
Huge amounts of slag are dumped into stream beds, where they overwhelm the ecosystem and leach into aquifers that supply drinking water. Sludge, on the other hand, is stored in abandoned mines and aboveground facilities. The leaching problem is the same, with toxic metals entering the drinking water supply. These coal pollutants often go undetected because testing is not routinely carried out.
Destruction of river, stream and reservoir ecosystems is common in areas where coal mining is carried out. Coal pollutants from the wind-blown soil of deforested mountaintops contributes to acid rain elsewhere. Loss of habitat for nearby animals further damages the natural environment. Pollutants find their way into the food chain, deforming and poisoning species as they go. These pollutants reach the top of the food chain when humans consume vegetables, meat and fish.
Effects on Humans
The effects of coal pollutants are many and well documented by the U.S. Centers for Disease Control. Asthma and lung cancer can be traced to the inhalation of coal pollutants. Toxic metals in the water can cause liver problems, kidney failure, many types of cancer and lymphoma, as well as cirrhosis. High levels of selenium in water can cause pulmonary edema and death, and mercury and lead are particularly toxic for children. The EPA currently urges stricter regulations for dumping of coal slag and sludge to combat coal mining pollution.