Total posts : 45366
I seriously doubt the government would come after you for re-transmitting EAS. In the end, as long as you are part15 compliant, you are legally considered background noise which can be ignored.
As far as supporting EAS on your part15 rig, this was my plan (if I ever get my station back on the air). I picked up a Midland weather radio and was going to use an Arduino to read the status from it. It has an LED that indicates if it has picked up an alert. I could use that as an input into the Arduino and have it change the audio source with a relay to come from the weather radio. Then, after about 5 minutes or so, it could clear the alert from the weather radio and change the audio source back to the playout system. You could certainly get fancy and have a serial interface to the playout PC so it could be aware of the switch, but that seems like overkill. You could also scale this back to just use an ATTiny13 or other small microcontroller.
This is the radio I intend to use for this: