The worst is methyl mercaptan, which smells like stale sewage.

Eww. (Isn't there another slightly less pongy mercaptan that's used to make mains gas, normally scentless, smell of something?)

I mean, it's true that modern paper mills do have the capacity to have quite a small footprint, but... hmm... I wouldn't've associated them with coexistence with a vineyard. Let's hope they can be forced to keep their act clean and clear.