[justlurking]

Can’t they put a big read ‘X’ on that runway so civilians know not to land there?

A big X means the runway is closed, permanently (a worldwide convention).

Ellsworth is an active AFB. They probably wouldn't appreciate that.

[Mr. K]

maybe not a red ‘X’ then... but some thing to differentiate?

An arrow pointing “that way to the civilian airport” maybe?