Page 663 - Environment: The Science Behind the Stories

the sCIeNCe behINd the stoRy

Mountaintop database of measurements made by
staff of the West Virginia Department
Removal Mining: of Environmental Protection. These
assessing the workers had measured concentra-
tions of pollutants in the waters of
environmental 1058 streams in West Virginia and had
Impacts recorded numbers and types of aquatic
insects in the streams.
Mountaintop removal mining has Palmer’s team first confirmed that
attracted a great deal of criticism from dr. margaret palmer, university of sulfate concentrations were tightly
environmental activists. But what do maryland linked with upstream mining activity.
scientific studies tell us about the They then looked for statistical correla-
impacts of this mining method? Is the and topsoil, alters topography, and tions between sulfate concentrations
outcry justified? compacts soil, less rain infiltrates and other water quality indicators, such
Stream ecologist Margaret the ground, and instead rain runs off as concentrations of selenium, iron,
Palmer of the University of Maryland quickly, causing flooding downstream. aluminum, and manganese. They found
and a team of 11 other scientists Moreover, when a valley is filled that concentrations of all these minerals
aimed to find out. They reviewed all with mined material, water that runs rose with concentrations of sulfates
the scientific literature on mountaintop through the fill emerges at the bottom (Figure 1, Top).
mining impacts. Writing in the journal carrying a brew of toxic substances. The researchers then graphed
Science in 2010, the team concluded Through the process of acid drain- their insect data against sulfate
that this method of mining causes age (p. 657), the acidic water carries concentrations (Figure 1, boTTom). All
“serious environmental impacts that dissolved heavy metals leached from types of insects decreased as sulfate
mitigation practices cannot success- the rock. concentrations rose, suggesting
fully address.” The team also con- Researchers with the United that the changes in water chemistry
cluded that published studies indicate States Geological Survey (USGS) brought about by mining were dimin-
“a high potential for human health carried out extensive water quality ishing insect diversity in the streams.
impacts.” surveys in Appalachian streams in the Water pollution from mining can
The Appalachian forests that late 1990s. For example, separate affect organisms higher on the food
are cleared in mountaintop mining teams led by Katherine Paybins and chain as well. Selenium is known to
are some of the richest forests for by James Sams took hundreds of bioaccumulate (p. 391) in organisms
biodiversity in the nation. Yet forest samples from diverse areas, chemi- and to cause birth defects (Figure 2).
clearance—and the loss of biodiversity cally analyzed the samples, and then EPA scientists surveying 78 streams
and ecosystem services—is merely the mapped their data, looking for geo- near mines in 2002 found that 73 had
most obvious impact. Palmer’s team graphic patterns. Their data clearly selenium concentrations above the
stressed that many more conse- showed that concentrations of pol- level at which studies have docu-
quences result when waste material lutants such as sulfates were strongly mented risks to insects, fish, and the
from mountaintop removal is dumped linked to upstream mining activities. birds that eat them.
into adjacent valleys, burying streams They also showed that this pollution Scientific research also docu-
and trees. and its impacts (such as biodiversity ments health impacts on people that
Once buried, headwater streams loss) are long-lasting. Indeed, many may be due to mountaintop mining.
are lost as ecosystems. Gone with studies show biodiversity declines in Health impacts come from inhaling
them are certain rare endemic spe- streams disturbed by mining, and no air pollution and dust, drinking con-
cies, as well as the ecosystem’s study has yet documented a recovery taminated groundwater, and eating
ability to cycle nutrients and pro- of stream life in the years after mining fish contaminated with selenium and
duce organic matter for downstream pollution. other toxic substances. A 2009 study
systems. Flash floods also result: Palmer’s team tested for water documented that people in moun-
Because mining removes vegetation quality impacts by tapping into a large taintop mining areas show elevated

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