You often hear defenders of mountaintop mining say, sure, active mining looks bad, but the environmental disturbance is only temporary.
The damage to water is not temporary, however, according to a new study by Duke University that was published in the peer-reviewed online Early Edition of the Proceedings of the National Academy of Sciences.
A team of researchers analyzed water samples from 23 sites along the Upper Mud River and its tributaries in West Virginia.
This was a good place to study the effects of surface mining because there are few homes, farms or underground mines to affect water quality.
And there are various stages of surface mining, from areas that are currently being stripped to sites that have been reclaimed for decades.
The analysis found that salinity and concentrations of trace elements, including selenium which is toxic to fish, increased in direct proportion to the cumulative amount of surface mining in the watershed.
Also, mines reclaimed almost 20 years ago continue to release effluents with salinity levels similar to active mines in the region.
The researchers tested conductivity, which measures dissolved solids and ions. All conductivity measurements taken downstream of mine discharge outlets exceeded levels harmful to aquatic life. At the two sampling sites upstream of any mines, conductivity levels were within an acceptable range.
The team also observed fish that had deformities consistent with selenium poisoning. In an intact aquatic system, the deformed fish would have become prey to healthier fish. So, we're talking about sick streams.
Other studies have shown that water quality and aquatic ecosystems are harmed by mountaintop mining.
This only stands to reason. When mountaintops are blasted and scraped away to reach coal seams, tons of rock and dirt are dislodged and pushed into nearby valleys or hollows, burying natural waterways.
Rain percolating through the rubble picks up trace elements, heavy metals and ions that otherwise would have stayed buried.
The Duke study, which fills a gap in data about the cumulative effects on water of multiple mountaintop mines, found what one professor called an "incredibly strong" correlation.
The question of cumulative effects is central to a lawsuit in Kentucky. A hearing officer last year ruled that state regulators had failed to properly consider the cumulative effects of a surface mining permit issued to Cambrian Coal in Pike County.
The mine is discharging water into tributaries of the Russell Fork of the Big Sandy River that are already degraded by heavy metals and salts from earlier mining.
Energy and Environment Secretary Len Peters overruled the hearing officer, however, and granted the permit to the company whose president, James Booth, was one of the co-chairs of Gov. Steve Beshear's inaugural committee.
The issue is still being litigated.
Federal law has long required state regulators to consider the cumulative effects before issuing a new strip mine permit, but in Kentucky that consideration has been absent or, at best, cursory.
The cumulative effect of that kind of regulation has been both an increase in flooding and a decline in stream quality.
Read the study at: http://www.nicholas.duke.edu/news/pnas%20201112381.pdf