Two of coal’s pollution legacies are acid mine drainage, the waste from mining coal, and fly ash, waste from burning coal. For years, some energy companies have put the waste into wet or dry storage impoundments.
Research has proved that combining fly ash with acid mine drainage can neutralize the acid. But a new study called, “Water quality implications of the neutralization of acid mine drainage with coal fly ash from India and the United States” found that the combination can be toxic, and include things like arsenic, lead and more.
A few years ago companies began using it in abandoned coal mines to neutralize some of the acid drainage.
In fact, putting fly ash into former mine sites is done in West Virginia. The study found that the combination can cause contamination harmful to human health.
“We realized that the properties of coal ash allows it to neutralize very acidic fluids like acid mine drainage,” AvnerVengosh, Professor of Environmental Quality at Duke University said.
The article was published in Fuel, an open-access, peer-reviewed research journal about fuel science.
Vengosh is one of the authors.
“Some fly ash has a very successful ability to neutralize acid mine drainage,” Vangosh said. “For example, [fly ash] in India, because of the chemistry of the original coal, they have less capacity to neutralize acid mine drainage. But coming back to the U.S., we found that the Appalachian fly ash, fly ash that we use so commonly in West Virginia, has pretty good capability of neutralization. However, because of the chemistry of the fly ash, and because it contains high concentrations of contaminants like arsenic, selenium, molybdenum, some elements that we know could hurt human health and the environment.
“When we [observed] the interaction of acid mine drainage with the fly ash, we actually found a negative impact on the treated effluent. So it’s like, pick your poison. On one hand, we are reducing the acidity of the acid mine drainage and it becoming no acid anymore, and therefore it’s very beneficial. However, on the other hand, we are generating what we call secondary contamination. So the fly ash would contribute contaminants into those effluent.”
Even though contaminants like arsenic occur naturally in the environment, it’s still dangerous to human health.
“Even a small amount of arsenic could be devastating for your health. So the fact that it’s coming from naturally occurring has nothing to do with its toxicity and its impact on human health,” Vengosh said. “This is really important. The quality of the water in West Virginia is one of the best I’ve ever measured in my life. Because of the spring and the water, the surface water is really clean. However, once you start to have mining, mountaintop mining, and or acid mine drainage, this high quality of water deteriorates very quickly.
“Water is becoming a major issue and one of the consequences of climate change. And global warming that we are seeing is that water in some areas is becoming more scarce. And we’re talking about water, the amount of water, but the quality in many parts of the world are being degraded because of climate change as well. So preserving clean water is really essential for our next generation to come.”
Vengosh said he’s not an activist, but he hopes to see new policies that protect public health based on this research.
“I think, is awareness that, regardless of your political belief, regardless where you come from, you have to understand the fact that coal ash is, and coal mining in general, presents challenges to our environment and to human health.
“I hope that there will be some kind of political consequences that people would say, ‘stop hurting, stop polluting our water,’ and that we are not putting ourselves in danger.”
Vangosh also wants to take this research on location in the “real world” and question the benefits of such disposal.
“I would expect the West Virginia authorities [WVDEP] would jump into that and test all the water that’s coming from those abandoned coal mines,” Vengosh said, “and to determine what are the actual risks on the ground for people who live there.”