In central Appalachia, a method called mountaintop removal is taking place and the coal industry may have declined because of the cheap natural gas rise up. Here in this place, a new web-based mapping tool shows the land laid bare details that are going back than three decades. The tool uses imagery satellite to map and identify the annual extent of mining activity across Kentucky, Tennessee, Virginia and West Virginia.

Between 1985 and 2015, the researchers estimate an average of 21,000 acres was converted to rubble and bare earth in Appalachia each year – an area about half the size of Washington, D.C., that is stated in the PLOS ONE journal. first author Andrew Pericak, who conducted the research in the lab of biology professor Emily Bernhardt at Duke University said that this analysis makes the total estimate since 1970about 1.5 million acres. This area is 18% larger than the state of Delaware and 3 % smaller than Everglades National Park. 

The method of mountaintop mining is a form of surface coal mining. In this coal, companies clear the forest from the hilltop and use heavy and explosive machines to blast the soil and expose to discover coal underneath the layers of soil. The remaining part of debris and rock is pushed into proximity valleys, burying under the streams of rubble called valley fill. 

According to advocates, the process offers the mining companies to harvest shallow seams of coal. However, with the advent of scientific evidence, it destroys fills the air with harmful contamination from the streams, destroys forests. 

Co-author Matthew Ross, previously at Duke and now a post-doctoral researcher at the University of North Carolina at Chapel Hill said that by determining the time of the coal mining activity is complicated of assessing these human and environmental impacts. In any year, the mining company would operate within an area that is permitted on their mining only. 

Previously it has been mapped that using satellite imagery for mapping surface mining in Appalachia. These updated in the year 2006 and give a mining snapshot in every 10 years rather than every year. 

The group used Google Earth Engine cloud computing platform to process the US government satellite images of invisible and visible light. This is reflected from the surface of the earth, taken over 31 years in a 74 country location. The team combined their mining areas and estimates the previous mining data.