Joyce, I am not from S.W. Virginia, but I keep a big Va. atlas and maps for genealogy. You might be following a reference for old Russell Co., a larger piece of land from which other counties were formed - like Scott Co., Va.
Right below the Russell Co. border there is a Scott Co. town in Virginia called Dungannon. Across the Clinch River is a prison institution. It looks like a Highway named 65 runs by it. Then there is a right turn on to state road 774,then a left on to what looks like 685, but the print is awfully small. My advice would be if you are actually going there, to stop at Dungannon and get additional information. I also see Sinking Creek running along Highway 65. The ends of both Cowan Creek and its parent creek, Sinking, cross into Russell Co., Virginia, but you need to start at Dungannon to get there. Good luck! Kay