I'm not 100% sure. If I had to wager, I'd say this was near Smoot Sand & Gravel. There were a few aggregate companies down there at one point, especially when the tracks extended further South onto the spit of land where Rock Creek exits into the Potomac.
on 2020-Apr-02 01:44:59 Christopher Parker said
The track alignment matches the spit of land where Rock Creek exits the Potomac. And nowhere else. Which makes this a very early photo. But that's consistent with the other photos in this batch.