(CNN) - The White House is shutting down a study examining the health effects of mountaintop removal coal mining.
The study began under the Obama administration and was being done by independent institutions chartered by Congress.
The mining technique is believed to deposit waste containing toxic minerals into groundwater, which could put residents at risk.
Coal mining advocates say studies showing a link between mountaintop removal mining and things like cancer don't take into account other lifestyle factors.
President Donald Trump branded himself as the pro-coal president.
"And for those miners, get ready, because you're going to be working your asses off, all right?" Trump said.
A letter from the Interior Department has directed the National Academies of Sciences, Engineering and Medicine to "cease all activities" on a study to determine whether people living near mountaintop mining sites in central Appalachia are more prone to certain diseases like cancer.
"The evidence we've seen so far in over two dozen articles and studies have shown higher cancer rates, higher rates of heart and cardiovascular disease," said Bill Price of Sierra Club West Virginia.
The agency said it "put on hold" $1 million in funding for the study because of its "changing budget situation."
The study focused on four states - West Virginia, Virginia, Kentucky and Tennessee - where mountain top coal mining is most prevalent.
Instead of drilling explosive blasts blow up mountains to get at the layers of coal inside. The waste from the process is dumped into steams and valleys nearby.
"President Trump is showing that he is looking out for the coal industry and the coal executives and not the people of Appalachia," Price said.
Since taking office, Trump has withdrawn from the Paris climate agreement, issued an executive order reopening federal lands to new coal leases and rolled back environmental rules including ones aimed at requiring the coal industry to monitor and report toxic mining waste in waterways.
"They stopped the requirement for companies to report. Now they've halted a study that would investigate whether there are any public health impacts for communities that are in the vicinity of mountaintop removal mining and that fits into an overall pattern in this administration of setting science aside," said Dr. Andrew Rosenberg of Union of Concerned Scientists.
The National Mining Association, which represents coal miners, pointed to a July study that said there is no conclusive evidence connecting mountaintop mining with health hazards, and questioned whether studying the health impacts is even necessary, saying "These mining practices today account for less than one percent of total U.S. coal production."
NEWS: Trump's Interior Depart has ordered National Academy of Sciences to halt study of health risks/harm caused by mountaintop coal mining pic.twitter.com/aO9lp9CNS3
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