While I haven't though enough on the issue to have much of an opinion on abolishing zoning completely, zoning seems like the wrong way of dealing with hazardous companies like that regardless. There is already an extensive permitting process and a mountain of regulation that you'd have to go through to open one of these companies, so why not enforce the safety perimeter through that?

It makes more sense to me to place the restrictions on the company/factory than the land itself, and building permits are already used by municipalities to negotiate location, etc.

That would prevent a hazardous factory from being built next to residences, but wouldn't prevent residences being built nearby after the factory is already there. For that, you'd need restrictions on the residences and/or the land.

Maybe a hybrid solution would work? Have a zone tied to the factory, no residential buildings within a certain radius of the factory, but if the factory shuts down or moves, the zone goes with it.

That's a really cool idea.

Is that the problem these cities have, too many fertilizer plants? It seems unlikely, but I haven't visited the West Coast in a few years. You might have better luck talking about natural gas storage.