With all due respect, I just have to point out to vwnate1, plumbers seldom deal with human waste. Maybe a few repair guys once in awhile or the unlicensed drain cleaner dudes. The decent wages come from the ability to install the piping systems that make buildings livable. I speak from 40 years experience. A good plumber has the same skillset as a good mechanic. Just applied to something else. So why are not auto mechanics compensated at the same rate? Because they haven't demanded it? As I think about that used motor oil from my 300D, which brown stuff is actually more toxic.?