[Quilla]

I believe the Plum Island refers to a remote island used by the government for secret testing as featured in a novel of the same name by Nelson DeMille.

[Calvin Locke]

I was referring to ETAs as source of revenue for Mayor Mike.

Plum Island, NY is a USDA-run quarantine island, iirc. Hence, some of the references to "animal" as a classification.

[Chris Talk]

Plum Island refers to a small island roughly 15 miles south of the point where the Connecticut /Rhode Island border hits Long Island Sound. It would thus seem to be about five miles on east from the very NE tip of Long Island NY. It is considered part of NY state even though it is a federal quarantine and hard to get into, IIRC.