Emeryville started as a mudflat on the Bay where they'd drive cattle to slaughterhouses and leather tanners. It smelled real bad so they did it way out in the middle of nowhere.

It sort of became the place for messy industry, when just burying the bad junk was considered sufficient.

Company I worked for had major construction project for their campus expansion, but it took a while to clear the PG&E transformer storage lot of decades of PCB leakage.

Poly chlorinated biphenyls are nasty. Almost as nasty as the heavy metal contamination of the Sherwin-Williams Paint factory across the way.

The merely-poisonous-at-quantity horseradish processing facility was a breath of fresh air... and is now part of the Pixar-plex.

What with all the major construction over the past 30 years, there have been ongoing cleanup efforts. I don't know how realistic my optimism is, but it's way cleaner than it was in the 1980s.