https://www.nbcbayarea.com/brchannel/Map-The-Chemical-Legacy...
TCE has a distinctive smell - sweet, like cookie dough or donuts. You'll know if you're in an area contaminated by it - I've smelled it at the Google Quad campus and some of the residential areas around it. (The area around Evandale is particularly bad, I've smelled it just driving through some of the residential streets there.) Some of the other chemicals used in semicoductor manufacture are odorless, though.
Most of the contamination is in industrial or office park zones, so I'd be more worried about your workplace than your home, and many of the spills are plain old gasoline (from service stations) which you can have anywhere.
