New Data Available on the Footprint of Surface Mining in Central Appalachia

The area of Central Appalachia impacted by surface mining has increased — by an amount equal to the size of Liechtenstein — despite a decline in coal production.

SkyTruth is releasing an update for our Central Appalachian Surface Mining data showing the extent of surface mining in Central Appalachia. While new areas continue to be mined, adding to the cumulative impact of mining on Appalachian ecosystems, the amount of land being actively mined has declined slightly.

This data builds on our work published last year in the journal PLOS One, in which we produced the first map to ever show the footprint of surface mining in this region. We designed the data to be updated annually. Today we are releasing the data for 2016, 2017, and 2018.

Mountaintop mine near Wise, Virginia. Copyright Alan Gignoux; Courtesy Appalachian Voices; 2014-2.

Coal production from surface mines, as reported to the US Energy Information Administration (EIA), has declined significantly for the Central Appalachian region since its peak in 2008. Likewise, the area of land being actively mined each year has steadily decreased since 2007. But because new land continues to be mined each year, the overall disturbance to Appalachian ecosystems has increased. From 2016 to 2018 the newly mined areas combined equaled 160 square kilometers – an area the size of the nation of Liechtenstein. One of the key findings of our research published in PLOS ONE was that the amount of land required to extract a single metric ton of coal had tripled from approximately 10 square meters in 1985 to nearly 30 square meters in 2015. Our update indicates that this trend still holds true for the 2016-2018 period: Despite the overall decrease in production, in 2016 approximately 40 square meters of land were disturbed per metric ton of coal produced – an all time high. This suggests that it is getting harder and harder for companies to access the remaining coal.

Active mine area (blue) and reported surface coal mine production in Central Appalachia (red) as provided by the US Energy Information Administration (EIA). The amount of coal produced has declined much more dramatically than the area of active mining.

This graph shows the disturbance trend for surface coal mining in Central Appalachia. Disturbance is calculated by dividing the area of actively mined land by the reported coal production for Central Appalachia as provided by the EIA.

Tracking the expansion of these mines is only half the battle. We are also developing landscape metrics to assess the true impact of mining on Appalachian communities and ecosystems. We are working to generate a spectral fingerprint for each identified mining area using satellite imagery. This fingerprint will outline the characteristics of each site; including the amount of bare ground present and information about vegetation regrowing on the site. In this way we will track changes and measure recovery by comparing the sites over time to a healthy Appalachian forest.

Mining activity Southwest of Charleston, WV. Land that was mined prior to 2016 is visible in yellow, and land converted to new mining activity between 2016 and 2018 is displayed in red.

Recovery matters. Under federal law, mine operators are required to post bonds for site reclamation in order “to ensure that the regulatory authority has sufficient funds to reclaim the site in the case the permittee fails to complete the approved reclamation plan.” In other words, mining companies set aside money in bonds to make sure that funds are available to recover their sites for other uses once mining ends. If state inspectors determine that mine sites are recovered adequately, then mining companies recover their bonds.

But the regulations are opaque and poorly defined; most states set their own requirements for bond release and requirements vary depending on the state, the inspector, and local landscapes. And as demand for coal steadily declines, coal companies are facing increasing financial stress, even bankruptcy. This underlines the importance of effective bonding that actually protects the public from haphazardly abandoned mining operations that may be unsafe, or unusable for other purposes.

We are now working to track the recovery of every surface coal mine in Central Appalachia. By comparing these sites to healthy Appalachian forests we will be able to grade recovery. This will allow us to examine how fully these sites have recovered, determine to what degree there is consistency in what qualifies for bond-release, and to what extent the conditions match a true Appalachian forest.

Monitoring the tailings dam failure of the Córrego do Feijão mine

On Friday, January 25th, the tailings dam to the Córrego do Feijão mine burst near Brumadinho, State of Minas Gerais, Brazil (the moment of failure was captured on video). Operated by Brazilian mining company Vale S.A., this incident recalls the collapse of Vale’s Samarco Mine in 2015 which unleashed 62 million cubic meters of toxic sludge downstream. As of Monday, the death toll reached 120, however, the full extent of damage is unknown. To monitor the impact, here is a Sentinel-2 scene of Córrego do Feijão from eighteen days before and seven days after the dam’s failure. As of February 2nd, approximately 2.85 km2 of sludge surrounds the region.

Sentinel 2 scene showing the extent of flooding as a result of the tailings dam failure. As a result of the failure, 3 billion gallons of mining waste were spilled.

This slider, below, shows the area near the town of Brumadinho before and after the dam failure with the inundation highlighted in yellow, it can be accessed here.

Updating SkyTruth’s mountaintop removal mining dataset

In Appalachia, it is not uncommon to see the effects that mountaintop removal mining have on the surrounding ecosystems.  As someone living in the great Mountain State of West Virginia, one of the projects that caught my interest when I started my internship at SkyTruth was their work mapping the extent of surface mines in central Appalachia.  There are many risks that come with this type of mining. Lung cancer, kidney disease, and birth defects are more likely in areas with high exposure to the toxins produced by mountaintop mining. There are currently no government funded long-term health studies in progress.  The last one, started during the Obama administration, was shut down in August 2017.

SkyTruth has been using the Normalized Difference Vegetation Index (NDVI) to detect surface mines.  Basically, this algorithm measures vegetation intensity over an area. So, areas with low NDVI scores – or low vegetation levels – show up as mines.  Seems simple enough. But the challenge to using NDVI to detect surface mines is that roads, parking lots, lakes, and buildings also have very low levels of vegetation, so they can confuse the algorithm into believing that they’re actually mines.  The two NDVI images below – one showing Charleston, West Virginia, and another showing a surface mine in central Appalachia – show how difficult it can be for the algorithm to tell things apart.

An NDVI image of Charleston, West Virginia.

NDVI image of Charleston, WV.

Compare that image with an image of surface mines in central Appalachia:

An NDVI image of surface mines in central Appalachia.

NDVI image of surface mines in central Appalachia.

Both of these images show areas with low NDVI scores (or low vegetation intensity).  Low NDVI scores are indicated by the darker shades in each of the images. The areas that have a high NDVI score are colored in lighter/whiter shades.  Using these images as an example, it’s easy to see how the algorithm that we’re using can get confused. Since things can look alike, we needed to figure out a way to help the algorithm determine which things were roads and buildings and which things were actually mines.  

SkyTruth’s surface mine mapping work relies on the use of a data mask to separate out the region’s urban areas, water features, and roads.  The mask is used to block out areas from the analysis which have a similar spectral signature to mines (basically roads, buildings, water, parking lots, etc.).  Since the surface mine mapping project is updated annually, the mask needs to be updated annually, too. First, I downloaded the area files, which are provided by US Census Bureau, and then I buffered the roads and water features by 60 meters. The buffer is to ensure that these areas are not picked up by the algorithm. The image below shows the mask that will cover the features that have a low vegetation index that could potentially be incorrectly identified as a surface mine.

An NDVI image of SkyTruth’s mountaintop mining study area with roads, water, and urban areas masked.

NDVI image of SkyTruth’s mountaintop mining study area with roads, water, and urban areas masked.

This next image shows how the mask covers an area like Charleston, West Virginia and blocks the algorithm from detecting it as a surface mine.  The other features in the image that have low vegetation intensity – like potential mines – are still visible as darkly areas in the image.

An NDVI image of Charleston, West Virginia with the mask applied.

NDVI image of Charleston, West Virginia with the mask applied.

SkyTruth, Appalachian Voices, and scholars at Duke University recently published the first-ever annual footprints of mountaintop mining in central Appalachia between 1985 and 2015.  You can learn more about it from SkyTruth’s lead author, Christian Thomas, or you can read the whole paper in PLOS ONE. The updated map will give SkyTruth, Appalachian Voices, and scholars at Duke University, the most current information about the footprint of surface mining in Appalachia, and it will allow them to update their annual footprints with 2016 and 2017.  I hope that this map will help inform the public about where surface mines in Appalachia are located, and that it will show people just how much of the Appalachian region is affected.

Satellite analysis shows steep increase in amount of land destroyed to mine a ton of coal in Appalachia

Today at 2:00 pm EST, the Open Access journal PLOS ONE published “Mapping the yearly extent of surface coal mining in Central Appalachia using Landsat and Google Earth Engine”. This paper, the product of a partnership between researchers at SkyTruth, Duke, and Appalachian Voices, provides the first comprehensive map of annual surface coal mining extent in Central Appalachia.

Mountaintop removal coal mining (MTM) is an immensely damaging practice which involves removing rock and soil which overlay coal seams using a combination of explosives and heavy machinery. The removed material is often deposited into valleys, in a practice known as valley fill. Mountaintop removal coal mining is responsible for disturbing thousands of square kilometers of land in Central Appalachia and is the region’s single largest source of land use change.

This animation shows the expansion of surface mining’s footprint (displayed in yellow) from 1985 to 2015 for a 31,000 square kilometer sub-region of the study area in West Virginia and Kentucky, and has county boundaries visible.

In addition to substantial disturbances directly visible on the surface of the land, MTM and subsequent valley fills have been shown to adversely impact stream health as seen by decreases in salamander abundance and aquatic macroinvertebrate diversity. MTM has also been associated with risks to public health in nearby communities, including higher rates of cancer and heart disease.

This study, published today, improves upon earlier SkyTruth work, and creates the first ever dataset of yearly active mining in Central Appalachia. Between 1985 and 2015 our study finds that 2,900 square kilometers (~720,000 acres) of this typically forested region has been cleared as a result of MTM. Coupling our results with our earlier work which dates back to 1976 we find that 5,900 square kilometers (~1.5 million acres) of Central Appalachian forest has been cleared. This is an area 18% larger than the state of Delaware, and roughly 3 times larger than the Great Smoky Mountains National Park.

This image shows a snippet of code used to create the annual mining footprint data, which is visualized in the bottom section of the image. Older mining in this visual is red; newer mining is yellow.

In addition to determining the spatial extent of MTM in Central Appalachia, the study also examined the relationship between the area of land being mined to coal production as reported to the United States Mine Health and Safety Administration (MSHA). Over the course of this study period (1985-2015) we see a threefold increase in the amount of land cleared to extract an identical quantity of coal (from 10 square meters of land per metric ton in in the 1980’s to 30 square meters in 2015).

This dataset is freely available for the public to download, visualize, and analyze the footprint of mining in Central Appalachia. To access all the data, please visit: https://www.skytruth.org/mtr-data-files/. To explore a subset of the data via an interactive web map, please visit: http://skytruthmtr.appspot.com/.

Mining to begin in downsized National Monument

Late last year, President Trump announced a massive scaling back of the boundaries of Grand Staircase-Escalante National Monument (GSENM), part of an even larger reduction of National Monuments in Utah, including nearby Bears Ears. Now a Canadian firm has announced plans to reopen a closed mine1 within the former boundaries of the old Grand Staircase-Escalante National Monument but just barely outside of the new boundaries. This appears to contradict President Trump’s declaration that this land was being returned “to the people, the people of all of the states, the people of the United States.” It also seems at odds with his recent bitterness toward Canada and his new trade war with our northern neighbor. What’s going on here?

Colt Mesa mining claim (yellow) and downsized National Monument (red area) superimposed on high-resolution imagery from Google Earth. Boundary data courtesy of The Wilderness Society.

In this image, we can see that the new Monument boundary is just 240 meters from the Colt Mesa mining claim with existing unpaved access roads only 150 meters away. The roads are marked in blue and criss-cross a dry riverbed. We expect these roads to be widened significantly and the area around the roads to be negatively impacted due to trucks and machinery. Given this proximity, the now much smaller National Monument will almost certainly be affected by heavy vehicular traffic day and night, and the attendant noise, dust, and diesel pollution.

The Colt Mesa mine relative to the Grand Staircase-Escalante National Monument, showing both the original Monument as designated in 1996, and the new, greatly reduced Monument.


The change in boundary illustrated by interactive slider, click here to view this in fullscreen mode.

This claim occupies 200 acres of previously protected land and, if this mining claim is developed as the company expects, we are expecting to see major changes to the area as they use increasingly destructive techniques to access the minerals beneath and dispose of the resulting “wasterock” and mine tailings.

An oblique view of the area.

The drastic downsizing of National Monument is being challenged in court by many organizations while the White House continues to insist this was about handing the power of conservation back to the state, and not about mining. The lawsuits are currently pending, so it remains to be seen if any land will be disturbed before these legal actions are resolved by the courts. In the meantime, we will be monitoring the area for signs of disturbance using Planet and other satellite imagery.

1 – The Colt Mesa mine was originally developed in the early 1970s to produce copper, silver, molybdenum, cobalt and uranium. It ceased production in 1974. It is a small mine by global standards, but these minerals are currently in high demand for use in electronics.