The mere threat of possible uranium mining in Southside Virginia has landed the Roanoke River on a list of the nation’s most endangered waterways.

The conservation organization American Rivers said the possibility of lifting a statewide ban on uranium mining would threaten the river and other rivers as well as drinking water supplies in the region.

The Roanoke flows from the Blue Ridge Mountains in Virginia to North Carolina’s Outer Banks. It provides drinking water to more than one million people in Virginia Beach, Norfolk and other communities.  Recently, Raleigh, applied to tap 50 million gallons a day from the basin.

The state has authorized a study to determine if more than 60,000 tons of uranium can be safely mined in rural south-central Virginia in what is thought to be the nation's largest undeveloped uranium deposit.

Environmental groups and other critics say uranium should not be mined in Virginia's highly populated areas and relatively rainy climate. They say they are worried that radioactive materials could cause cancer or other illnesses and do long-term harm to animals and plants.

“This uranium operation would generate millions of tons of toxic, cancer-causing waste,” said Peter Raabe of American Rivers. “We’re talking about a radioactive legacy that would last for generations.”

The General Assembly banned uranium mining soon after the uranium was discovered more than 25 years ago. Supporters of mining, including the company that owns the land, hope to persuade legislators to repeal the ban.

“It is remarkable how these groups ignore science, public policy and common sense so consistently,’’ aid Patrick Wales, project manager for Virginia Uranium Inc., which wants to mine the uranium. “The tragic part is that they do so at the expense of jobs and American energy independence.”