Ah, Yates County, New York. Those are all over the place there, they have many XT22s and the Penetrators are part of a Nuclear Power Plant warning system, as far as I know.
Here are a few:
I really like the way that Ginna mounted the sirens at existing locations like this, it is a really neat and clean look... I imagine it would also be more economical than having a separate pole for the power plant sirens. As noted, certainly not something you see every day but a good example of thinking outside of the box.