Two U.S. congressmen, one of whom is from Kentucky, have introduced a bill requiring a federal study of the health effects of mountaintop removal coal mining.
The lawmakers claim mountaintop removal mining contaminates water supplies with heavy metals, which makes people sick.
The Kentucky Democrat behind the bill says the legislation would provide families in mining communities with answers to questions about potential health impacts.
He also says, if the study proves mountaintop mining is unsafe, it should be outlawed.