An independent evaluation of potential health risks occurring near mountain top removal coal mining sites was stopped by the Trump administration on Aug. 21 when it sent a letter to the National Academy of Sciences ordering to stop its work on the project immediately.

The move is yet another step the administration has taken to remove policies that it views as hindrances to the production and use of coal. Earlier this year, Congress repealed an Interior rule meant to protect streams from mountaintop removal mining waste. The Department of Interior has also overturned a moratorium on new coal mining on federal land, and the Environmental Protection Agency (EPA) has started repealing numerous regulations meant to reduce pollution from coal use. The Trump administration also removed the United States from the Paris Climate Accord that was aimed at reducing carbon emission and in August, the administration made the decision to disband the federal advisory panel for the National Climate Assessment, a group aimed at helping policymakers and private-sector officials incorporate the government’s climate analysis into long-term planning.

In its decision to halt the study on Mountaintop removal projects the Interior Department’s Office of Surface Mining (OSM) said it had begun an agency-wide review of its grants and cooperative agreements in excess of $100,000, largely as a result of the department’s changing budget situation, the National Academy said in a statement.

The Hill reported that the Interior Department’s Office of Surface Mining (OSM) last year, under then-President Obama, had commissioned the research into the possible connections between certain health risks and living near current or former surface mining sites in Appalachia. The OSM committed $1 million to the two-year effort after West Virginia officials requested it in 2015.

Environmentalists have long argued that mountaintop removal releases pollutants into water and air, causing cancer, birth defects, cardiovascular illnesses and more health concerns.

Michael Hendryx, an Indiana University health science professor, told House lawmakers in 2015 that his studies have linked mountaintop removal to increased lung cancer, heart and kidney disease, and other ailments.

The National Mining Association has repeatedly disputed such findings and funded research to try to debunk the conclusions.