This story was originally Appear in cereals and is climate desk Cooperation.
Appalachian states like Kentucky have a long and turbulent history of coal and mountaintop removal — a mining process that uses explosives to clear forests and scrape soil to gain access to the underlying coal seams. For years, researchers have warned that the land created by hilltop removals lacked vegetation to prevent runoff and could be more prone to flooding. Without trees to buffer the rain and soil to absorb it, the water would gather and flow to the path of least resistance – downhill.
In 2019, two Duke University scientists analyzed flood-prone communities in the region for Inside Climate News, identifying “the areas most affected by mining.” That includes many of the same Eastern Kentucky communities where river levels rose 25 feet in 24 hours over the past week.
“The findings suggest that long after coal mining has ceased, its legacy … may continue to be a toll on residents living in the hundreds of lower Appalachian mountains,” James Bruggs of Inside Climate News in time.
Now, in 2022, the findings are sadly prescient. From July 25-30, flash floods and thunderstorms in eastern Kentucky brought more than 4 inches of rain an hour and local rivers swelled to historic levels. The floods have claimed at least 37 lives so far.
Nicolas Zégre, director of the Mountain Hydrology Laboratory at West Virginia University, studies the hydrological impact of mountaintop removal and how water moves through the environment. While it’s too early to know how much the region’s mining history contributed to this year’s floods, he said he sees Appalachia as a “climate zero” region, an area based on the coal industry that contributes to global temperatures rising and carbon emissions. atmosphere.
“Whether it was the 2016 floods in West Virginia or the recent floods in Kentucky, there was more rainfall because of warmer temperatures,” Zegre said, “and then the rainfall fell on deforested land.”
For some area scientists, surface mining isn’t the only factor behind the increased flooding. A 2017 Environmental Science and Technology study looked at how removing hilltop mining could actually help store precipitation. When the top of the mountain is shaken by the explosion, the remaining material is filled into an area called the valley fill. According to the authors, “mined watersheds with valley fills appear to store precipitation for a considerable period of time.”
The study does point out that the materials in valley fills often contain toxic chemicals and heavy metals produced during mining. These compounds are then washed into streams during heavy rains, a process known as alkaline mine drainage. According to a 2012 study, also from Environmental Science and Technology, alkaline mine drainage has polluted 22 percent of all rivers in Central Appalachia.