Read the report here.CHARLESTON, W.Va. -- Threats from continued mountaintop removal and expanded oil and gas drilling have landed two West Virginia waterways on an advocacy group's annual list of the nation's most endangered rivers.American Rivers put the Gauley and Monongahela in its yearly report, America's Most Endangered Rivers, released Wednesday.The Washington, D.C.-based group cited ongoing mountaintop removal in the Twentymile and Peters Creek watersheds as a major threat to the Gauley and pollution from oil and gas drilling as a growing danger to the Monongahela.The No. 1 river on the 2010 endangered list is the Upper Delaware, where gas drilling threatens the drinking water for 17 million people across New York and Pennsylvania."The threats facing this year's rivers are more pressing than ever, from gas drilling that could pollute the drinking water of millions of people, to the construction of costly and unnecessary dams, to outdated flood management that threatens public safety," said Rebecca Wodder, president of American Rivers.In its report on the Gauley, American Rivers noted that the river is internationally known for its whitewater, but that coal mining in the tributary watersheds "flattens mountaintops, buries streams under debris and pollutes water.""The U.S. Environmental Protection Agency and cooperating agencies must stop the permitting of mine activity that harms the clean water and natural areas that are essential to the health and heritage of Appalachian communities," American Rivers said.In 1988, the Gauley received some federal protections as the Gauley River National Recreation Area, under legislation pushed through by Rep. Nick J. Rahall, D-W.Va. Rahall, though, has opposed EPA's efforts to crack down on pollution from mountaintop removal mining.Previously, American Rivers listed the Coal and Big Sandy rivers as endangered because of mountaintop removal mining.American Rivers said that the Monongahela provides "exceptional wildlife habitat, recreational opportunities, and drinking water for hundreds of thousands of people in West Virginia and Pennsylvania."But, the group said, the Mon has "become highly threatened by toxic pollution arising from the recent surge of natural gas extraction activities in the region overlying the Marcellus Shale formation."The federal government and the states of West Virginia and Pennsylvania must act now to prevent further pollution associated with Marcellus Shale exploration and protect the already highly vulnerable water quality of the Monongahela River Basin," the group said.In 2004, American Rivers listed the Mon -- along with the Allegheny River -- as among the most endangered rivers, citing at the time the millions of gallons of polluted coal-mining waters building up in old mine tunnels.Other rivers listed as endangered in this year's report included the Sacramento-San Joaquin River in California, the Little River in North Carolina, the Cedar River in Iowa, the Upper Colorado River, the Chetco River in Oregon, the Teton River in Idaho, and the Coosa River in Alabama.Reach Ken Ward Jr. at firstname.lastname@example.org or 304-348-1702.