> Like, the Silicon Valley is the US' biggest cluster of Superfund sites by far

Source? My understanding was that NJ was the worse.

Wikipedia shows 94 SF sites in CA: https://en.wikipedia.org/wiki/List_of_Superfund_sites_in_Cal...

And 115 in NJ: https://en.wikipedia.org/wiki/List_of_Superfund_sites_in_New...

And of course, CA is _much much_ larger. If we look at the entire bos/wash corridor, it's huuugely than CA.