MORGANTOWN, W.Va. (AP) — Federal mining regulators have told the National Academies of Sciences, Engineering and Medicine to halt its study of the health risks for people living near Appalachian surface coal mines.

The Interior Department's Office of Surface Mining Reclamation and Enforcement, which announced last year it was funding the $1 million study, said in an Aug. 18 letter that the department has begun reviewing grants over $100,000 largely for budget reasons.

"The National Academies believes this is an important study and we stand ready to resume it as soon as the Department of the Interior review is completed," spokesman William Kearney said Monday. Two public meetings scheduled this week in Kentucky will be held, he added.

Results were expected next spring. Some studies have linked living near mountaintop removal mines to greater risks of cancer, birth defects and premature death.

The Office of Surface Mining Reclamation and Enforcement didn't immediately reply on Monday to requests for comment.

West Virginia state officials requested the federal study in 2015. State health and environmental agencies said Monday that they weren't notified of the grant review and will keep providing information to the study if it resumes.

President Donald Trump, who took office this year and has often criticized regulations issued by the Obama administration, appointed Montana Congressman Ryan Zinke to head the Interior Department, citing his track record "championing regulatory relief" and "responsible energy development."

The task of the National Academies of Sciences committee is to identify the geological and geochemical characteristics of mining operations, the regulatory framework, relevant scientific literature and its sufficiency, and potential short- and long-term human health effects.

Committee Chairman Paul Locke, a professor at Johns Hopkins School of Public Health, said at a West Virginia hearing in May that the study will require a consensus draft report among the members, several of them professors with expertise including mineral engineering, biosystems, epidemiology, geology and environmental medicine. The study, which will be subject to peer review, focuses on West Virginia, Virginia, Kentucky and Tennessee.

Representatives of Coal River Mountain Watch, West Virginia Highlands Conservancy and Ohio Valley Environmental Coalition told the committee that scientists should pay close attention to the silica and fine particulates produced by blasting and digging, as well as water pollution.

The West Virginia Coal Association said the state's surface mine production, based mainly in the southern region of the state, has dropped from about 44 million tons (40 million metric tons) of coal in 2012 to about 14 million tons (13 million metric tons) last year.