The following editorial appeared in Thursday's Washington Post: During the campaign and after his election, President Obama left environmentalists in coal country with the distinct impression that he was going to do away with mountaintop removal mining in the Appalachians. That's where coal companies expose coal seams by stripping the dirt and rock covering them or blasting the tops of mountains to bits with dynamite and then, under legally defined conditions, dump the debris into valleys. It's a particularly destructive practice, but it's legal. And it will remain so under a memorandum of understanding the Obama administration will announce Thursday. When the Environmental Protection Agency announced in March that it was going to review 200 pending surface mining permits spread over six states, many environmentalists believed it marked the beginning of the end of the technique they say has buried 2,000 miles of streams and clipped the tops off 500 mountains. But last month the EPA blocked just six of 48 proposed projects -- and Thursday's agreement among the Army Corps of Engineers, the Interior Department and the EPA puts in place an interagency plan that the administration believes will strengthen regulations for mountaintop removal projects while allowing them to continue. It will more vigorously enforce a 1983 rule requiring a 100-foot buffer between valley waterways and debris and toughen the permit review process. While Mr. Obama may have wanted voters to believe otherwise, he never flat-out said he would end this brand of mining. His decision reflects energy and political realities. Coal will remain an essential energy source for some time, while ending mountaintop removal mining would require action in Congress. There it would be opposed by coal-state members whose help Mr. Obama needs to get the more ambitious climate-change bill passed. Would we rather see a better way to extract coal? Certainly. But vigorous enforcement of the laws can help protect the environment until viable energy alternatives render the practice unnecessary. 