Blame coal mining for Appalachia's salty rivers

Forget sipping fresh mountain spring water — Appalachia has a salty river problem and coal mining is to blame. The salt leaches into the streams and rivers from crushed rock and coal that gets deposited in valleys from mountaintop-removal mining. The leeching then causes consistently higher levels of salt in the water, damaging the ecosystems that lie downstream.

It's not just Appalachia that is suffering from this problem, though it is hit the hardest. High salinity in river and stream water can cause significant issues for a large portion of the eastern US, highlighting a relatively unknown aspect of the largely harmful practice of coal mining. Mountains are being changed by the mining and the surrounding land is being transformed — that is, damaged — by the crushed mountain debris that results.

Researchers with Duke University and the University of Wyoming detailed this problem in a newly published study, explaining that there are many rivers and streams in Appalachia that are running salty for up to 80-percent of every year. The epicenter of their study was the heavily-mined Mud River Basin in West Virginia; there are four watersheds that run into this basin, as well as many valley fills created by depositing crushed mountain rock and other debris into the neighboring regions.

The presence of this rock introduces a second big problem, namely the excessive presence of highly porous rock in these valleys. When it rains, a large amount of the fresh water is absorbed by the rocks, preventing the water from running off as usual and skewing when the streamflows are present. Leeched salt from the crushed rock, meanwhile, makes the water and surrounding earth salty.

The researchers found that at least 7-percent of Appalachia's land has experienced disruption due to this coal mining practice. The combination of altered streamflow seasons and higher salinity can have a major impact on large regions, affecting both water used for agriculture and water used for urban regions. The problem isn't limited to just Appalachia, but serves to underscore the environmental issues that can happen anywhere that mountaintop-removal coal mining is conducted.

SOURCE: EurekAlert