Surface coal mining, including mountaintop removal mining, was responsible for the clearing of more than 7 percent of the land in central Appalachia — or an area about three times the size of the Great Smoky Mountains National Park — from the mid-1970s through 2015, according to new research.

A total of almost 2,300 square miles of land in central Appalachia was cleared by surface mining during this period. Mountaintop removal, the most controversial type of surface mining, relies on cutting off the peaks of mountains to access the mineral below.

For decades, environmental activists have been pushing for a ban on mountaintop removal coal mining. The mining practice takes place primarily in eastern Kentucky, southern West Virginia, southwestern Virginia, and eastern Tennessee.

Supporters of mountaintop removal mining contend the process allows mining companies to extract shallow seams of coal they could not access through traditional underground mining. But a growing body of scientific evidence shows the practice destroys forests, fills the air with harmful dust, and contaminates nearby streams.


By merging U.S. Geological Survey Landsat satellite imagery and the Google Earth Engine, a team of researchers created a study and dataset that shows the effects of mountaintop removal on a year-by-year basis. The researchers also used an earlier collection data, covering the mid-1970s through 1984, to come up with the 40-year total.

The study was published Wednesday in the journal PLOS ONE by researchers from SkyTruth, Duke University and Appalachian Voices. The researchers said they plan to update the data on an annual basis.

The researchers estimate that between 1985 and 2015, an average of 21,000 acres was converted to bare earth and rubble in central Appalachia each year — an area about half the size of Washington, D.C.

“It’s important for policymakers, scientists and the public to see and understand the full scope of landscape disruption that Appalachia is burdened with as a consequence of our persistent economic dependence on coal mining,” Christian Thomas, a geospatial analyst with SkyTruth, said Wednesday in a statement.

The nonprofit SkyTruth use satellite imagery and geospatial data to create visuals and resources to inform environmental advocates, policymakers, the media, and the public. The group created a timeline of active mining for any location in central Appalachia or time period between 1985 and 2015.


Reliable, up-to-date estimates of the mining industry’s footprint have been hard to find. In any given year, a mining company may be operating only within a small portion of the area shown on their mining permit. The tool developed by Duke researchers, working with SkyTruth and Appalachian Voices, reveals where mountaintop mining is underway on a finer time scale, and makes it easier to keep the data current.

The study’s researchers are hoping their findings help other experts better understand the environmental and human health impacts of mountaintop coal mining. Last year, the Trump administration ordered government researchers to stop work on an independent evaluation of potential health effects from mountaintop removal coal mining.

During the last year of the Obama administration, the Department of the Interior’s Office of Surface Mining commissioned research into the possible connections between certain health risks and living near current or former surface mining sites in Appalachia.

But last August, the Office of Surface Mining sent a letter to the National Academy of Sciences, which it had contracted to do the independent review, asking it to stop its work immediately on the $1 million contract. The Trump administration said the suspension of the research was to give it time to determine whether the research was a responsible use of taxpayer money.

Despite the Trump administration’s impeding efforts to study the impacts of mountaintop removal, Andrew Pericak, a research analyst at Duke University who worked on the study, believes the new data in the study will inform independent scientific research and provide a better understanding of the environmental and human health impacts of mountaintop coal mining.


“Researchers will be able to align historic data on water quality or species distribution, for instance, with this new understanding of exactly when and where mining occurred,” Pericak said in a statement.

Coal producers have not seen the same kind of progress in reducing their environmental footprint as the oil and gas sector.

Oil and gas companies are now able to drill multiple wells on a single well pad, which reduces the land impact. They also can drill horizontal wells that can stretch up to two miles underground, decreasing the number of wells needed to produce the same amount of oil.

Coal producers are seeing opposite results. In the 1980s, 10 square meters, or about 110 square feet, of land was disturbed per metric ton (2,200 pounds) of coal produced. By 2015, 30 square meters, or about 330 square feet, was disturbed to produce the same amount of coal, a threefold increase, according to the study.

Source: Appalachian Voices

The research team processed more than 10,000 individual Landsat satellite images. The team was able to identify areas with an absence of forest cover in contrast to surrounding, forested areas on a yearly basis.

After excluding known roads, bodies of water, and cities, the team labeled any remaining deforested areas as likely surface mines. They were able to validate the findings by manually spot-checking the results against aerial survey photography and other imagery.

Emily Bernhardt, one of the study’s co-authors, is a professor in the biology department at Duke University and is using the data to understand more precisely how mountaintop mining affects water quality, how far the effects extend downstream, and how long they persist. In a statement Wednesday he said, “Any scientist interested in studying the impacts of mountaintop mining can now see exactly where mines are in the landscape and how long those impacts have been active.”