Aquatic ecosystems suffering extensive damage
By Summit Voice
SUMMIT COUNTY — Strip mining and mountain-top removal has degraded water quality in more than 20 percent of West Virginia’s rivers and streams to the point that many of them are probably impaired under state water quality standards.
Increased salinity linked with sulfates is wiping out insect populations far downstream from mine sites, according to research by scientists with Duke and Baylor universities, who used NASA satellite images and computer data to map the extent of surface mining across a 12,000-square-mile area of the southern West Virginia coalfields between 1976 and 2005.
Overall, mining companies have converted more than five percent of the land into mine sites and buried 480 miles of streams beneath adjacent valley fills during this period.
“Our findings offer concrete evidence of the cumulative impacts surface mining is having on a regional scale,” said Emily S. Bernhardt, associate professor of biogeochemistry at Duke’s Nicholas School of the Environment. “The relationship is clear and direct. The more mining you have upstream, the higher the biological loss and salinity levels will be downstream, and the farther they will extend.”
“It’s important to recognize that surface coal mining pollution doesn’t stop at mine-permit boundaries,” said Brian D. Lutz, a postdoctoral associate in Bernhardt’s lab.
The study shows that the impacts of mining are spreading far beyond the boundaries of active mining operations.
Bernhardt said she and her team “set out to understand how the large and growing number of surface mines is affecting water quality throughout Appalachia.”
Based on the research, at least 1,400 miles of streams in the region are at risk of substantial degradation from mining.
“Our analysis suggests that mining only five percent of the land surface is degrading between 22 percent and 32 percent of the region’s rivers,” Lutz said.
Substantial declines in insect diversity began to occur when companies had mined as little as one percent of upstream land, the analysis showed. In areas where companies had converted about five percent of the land into mines, sensitive species such as mayflies and stoneflies had vanished or declined to an extent that the streams would qualify as biologically impaired under criteria set by the state of West Virginia.
The designation means the streams could be placed on a list of waterways that the state must take steps to rehabilitate.
“What is so compelling is that we found many different types of organisms are lost downstream of surface coal mines, and most of them begin to disappear at similar levels of mining,” said Ryan S. King, associate professor of biology at Baylor. “Our analysis shows that coal mining is leading to widespread declines in aquatic biodiversity in Appalachian streams.”
The study was published this week in the peer-reviewed journal Environmental Science & Technology, documents substantial losses in aquatic insect biodiversity and increases in salinity linked to sulfates and other pollutants in runoff from mines often located miles upstream.