Putting some SH*T in the sewer.

I took this in my taxi ride to school today. This guy was parked in the middle of the road pumping stuff out of his truck into the sewer. I have no idea what it was and am glad I didn't smell it cause it looked a little nasty. It just amazes me that he couldn't find a convenient place to do it. I also wondered what the heck he was pumping but am relieved that I don't know exactly what it was.