I came to DC in ‘79. Back then and for years after, Safeway dominated the city and Giant dominated the suburbs. Which sheds no light at all on whether there was a Safeway in Potomac Village at the intersection of Falls Road and River Road in the early 1980’s. There is now. This is FR, so someone will probably be along with the answer soon.
Yes, there was a Safeway there at that time. Was still there last time I visited sometime in the 00s.
That page, of course, doesn't go to Safeway so those folks aren't going to get a response. But I'd be surprised if someone hasn't already stopped in the store to ask. And probably no one in the store has the slightest idea.