While working my way through college oh so many years ago, I had a job sampling waste water discharges for environmental compliance checking. I visited many sewage treatment plants, paper mills, rendering plants, and chemical plants, but by far and away the worst stink I have ever encountered was the Cozy Kitten cat food plant in Pascagoula Mississippi on a hot summer’s day. Think railroad cars packed full of fish heads, shrimp hulls, and the assorted other refuse from a variety of seafood processors all along the Gulf Coast sitting on a railroad siding in the hot sun waiting (sometimes for days at a time) to be brought into the plant for processing. When the wind was right, it totally overpowered the smell of the paper mill next door! :eek:
I can relate. I grew up in this town.
Heh, fun to watch that video again after all these years. The Spreckels is no longer there, but that Swirly stand is. 
Oh, I should add that the aroma is also no longer there. (I can confirm it was BAD!) The local explanation was that Spreckels had a few acre feedlot where they fattened cattle on the waste from their sugar processing. The waste from the cattle was even worse than typical cattle manure smell - apparently the added sugar in their diet gave their manure an added odor of death rot.
Paper mills alone don’t smell, but they often have a pulp mill nearby as well and those can smell. I used to live a few hundred meters from a smallish paper mill but there was no pulp mill and thus no smell whatsoever. Worked there a few summers as well, I can’t remember any part of the mill smelling especially bad. Hot and humid and noisy yes, smelly no - nice place to work really.
Had a meat processing plant along my paper route on the other hand and that smelled really bad, even in winter. There was a fairly sizable suburb right next to it and the smell was bad there as well, I kept on wondering whether they get used to it and how bad it gets in the summer.
As noted here on the SDMB a few years back, tanning leather is a pretty horrid job.
The job was tolerable because the air was rapidly vented outside. The neighbors didn’t like it all that much, however.
Did they use the heads for headcheese? I’m not trying to be funny; this is a serious question.
My brother says that cheek meat tacos are some of the best food he’s ever eaten.
Not the cow heads no, they were used for tongue and the cheeks and other offcuts ground up for dog meat.
The pig heads were used for brawn which I suspect is the same thing as “headcheese” (I’m not familiar with that term though)
I used to deliver pizza in Longmont, CO and the worst runs were the ones that went south of the turkey processing plant. It was like running a gauntlet. What a nauseating reek.