There’s a new study out today that presents the first real effort to compare the environmental damage from mountaintop removal mining to the energy benefits from the coal that’s produced. Here’s what’s reported in the press release from Duke University:

To meet current U.S. coal demand through surface mining, an area of the Central Appalachians the size of Washington, D.C., would need to be mined every 81 days.

That’s about 68 square miles — or roughly an area equal to 10 city blocks mined every hour.

A one-year supply of coal would require converting about 310 square miles of the region’s mountains into surface mines, according to a new analysis by scientists at Duke University, Kent State University and the Cary Institute for Ecosystem Studies.

Creating 310 square miles of mountaintop mine would pollute about 2,300 kilometers of Appalachian streams and cause the loss of carbon sequestration by trees and soils equal to the greenhouse gases produced in a year by 33,600 average U.S. single-family homes, the study found.

Here’s the abstract of the study, which appears online today in the peer-reviewed journal PLOS ONE:

While several thousand square kilometers of land area have been subject to surface mining in the Central Appalachians, no reliable estimate exists for how much coal is produced per unit landscape disturbance. We provide this estimate using regional satellite-derived mine delineations and historical county-level coal production data for the period 1985-2005, and further relate the aerial extent of mining disturbance to stream impairment and loss of ecosystem carbon sequestration potential. To meet current US coal demands, an area the size of Washington DC would need to be mined every 81 days. A one-year supply of coal would result in ~2,300 km of stream impairment and a loss of ecosystem carbon sequestration capacity comparable to the global warming potential of >33,000 US homes. For the first time, the environmental impacts of surface coal mining can be directly scaled with coal production rates.

Brian D. Lutz, assistant professor of biogeochemistry at Kent State, who began the analysis as a postdoctoral research associate at Duke’s Nicholas School of the Environment last year, said that while  many studies have documented the severity of surface mining’s impacts on local ecosystems, few have quantified the region-wide extent of the damage and provided the metrics needed to weigh the environmental costs of mountaintop mining against its economic benefits. Lutz said:

This is a critical shortcoming, since even the most severe impacts may be tolerated if we believe they are sufficiently limited in extent.

Co-author William H. Schlesinger, president of the Cary Institute of Ecosystem Studies in Millbrook, N.Y., and   James B. Duke Professor Emeritus of Biogeochemistry and former dean of Duke’s Nicholas School, said the new 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.” Schlesinger added:

Tremendous environmental capital costs are being incurred for only modest energy gains.