Study puts strip-mining damage in perspective
CHARLESTON, W.Va. -- Mountaintop removal in Appalachia causes tremendous environmental damage while producing a relatively small amount of coal, according to a new scientific study published Wednesday.
The analysis by researchers at Duke University and Kent State University found that to produce nearly 2 billion tons of coal between 1985 and 2005, coal operators mined about 2,000 square kilometers of land.
About 11,500 tons of coal was produced for every hectare of land disturbed, and each ton of coal resulted in 0.25 centimeters of being impaired and 193 grams of potential carbon sequestration by forestland being lost, the study said.
Co-author and Duke bio-geochemistry professor Emily Bernhardt said those numbers might not sound like much, until they are put in perspective, such as in terms of lost ability for forests to capture and store greenhouse gases.
"Based on the average sequestration potential of formerly forested mine sites that have been reclaimed into predominantly grassland ecosystems, we calculate it would take around 5,000 years for any given hectare of reclaimed mine land to capture the same amount of carbon that is released when the coal extracted from it is burned for energy," Bernhardt said.
Study authors used satellite images and historic county-by-county coal production data to measure the total area of land mined and coal removed in the Central Appalachian coalfields between 1985 and 2005. The team calculated the average per-ton environmental costs of this activity by using previously reported assessments of the extent of stream impairment and loss of carbon sequestration potential.
Among other things, they found that to meet current U.S. coal demand through surface mining in Appalachia, about 68 square miles -- an area the size of Washington, D.C. -- would need to be mined every 81 days.
A one-year supply of coal would require converting about 310 square miles of the region's mountains into surface mines, according to the study. This would in turn pollute about 2,300 kilometers of streams, the study said.
The study, published online Wednesday by the peer-reviewed journal PLOS ONE, is the first to try to put an environmental price tag on mountaintop removal mining, said Brian D. Lutz, an assistant professor of bio-geochemistry at Kent State.
While many studies have documented environmental damage from mountaintop removal, few have tried to quantify the region-wide extent of damage and provided comparisons needed to weigh the costs against the economic benefits.
"This is a critical shortcoming," Lutz said, "since even the most severe impacts may be tolerated if we believe they are sufficiently limited in extent."
Co-author William Schlesinger, professor emeritus at Duke's Nicholas School of the Environment and president of the Cary Institute of Ecosystem Studies, said, "This analysis shows that the extent of environmental impacts of surface mining practices is staggering, particularly in terms of the relatively small amount of coal that is produced."
Reach Ken Ward Jr. at email@example.com or 304-348-1702.