Covering Up Their (Messy) Tracks

Saw this a few mornings ago, while waiting for the train in to work. Is it sawdust? Debris? It appears to have been left or placed here on purpose, but I’m at a loss for what this might actually be.
Maybe there was more work done on the tracks, and this was just residue from that.
I’m used to fast-moving trains going up and down these tracks. So the idea of anything being “on” the tracks like this is a little odd to me.
// Edit: I spotted this a few days ago, and don’t recall seeing it the following day. Gone as quickly as it appeared.
// Edit 2: Actually, it still is there. I’m just not very observant.
Related:
I’ve Been Working on the Railroad…
No One Likes the Metra Quiet Car

Looks like to corn to me. It’s not unusual for hopper cars to “leak” some material as they stop and start in a jerking motion. A close up might be needed, ha.
Dad (December 23, 2015 at 10:10 am)Could be – if it’s still there, I’ll take another look!
avoision (December 24, 2015 at 10:16 am)