CONGRESS long ago established a basic principle governing the extraction of coal from public lands by private companies: American taxpayers should be paid fair value for it. They own the coal, after all.

Lawmakers set a royalty payment of 12.5 percent of the sale price of the coal in 1976. Forty years later, those payments remain stuck there, with actual collections often much less. Studies by the Government Accountability Office, the Interior Department’s inspector general and nonprofit research groups have all concluded that taxpayers are being shortchanged.

This is no small matter. In 2013, approximately 4o percent of all domestic coal came from federal lands. A recent study by the independent nonprofit research group Headwaters Economics estimates that various reforms to the royalty valuation system would have generated $900 million to $5.6 billion more overall between 2008 and 2012.

This failure by the government to collect fair value for taxpayer coal is made more troubling by the climate-change implications of burning this fossil fuel. Taxpayers are already incurring major costs in responding to the effects of global warming. Coastal infrastructure is being battered by sea rise and storm surges; forests are being devastated by climate-aided pest infestations; and studies are suggesting that temperature rises have increased the likelihood of devastating droughts in California.