159.300 MHZ was the simplex channel being used for emergency scene operations for years. It is still programmed into the radios.
The newly acquired frequency pairs that the OP listed is used as the new emergency scene operations channel. It can be toggled for simplex operation as well.
Union County EMA has a volunteer operations division providing rehab support, HAZMAT operations, traffic control and other functions. They are very much using the new repeater which is at their station on Northwest Parkway for voice communication during emergencies.
Siren tones are still broadcast over 154.250 MHZ every Wednesday at noon.
They are always looking for local volunteers and many of which are HAM operators. They have a communications section and a cool array of amateur radio equipment on hand as well.
Source: I programmed the radios.
I suspect this may be used for their tornado sirens. To the best of my knowledge, everything public safety in Union County is on MARCS.
It's possible they could use it as a backup in case MARCS takes a dump, also. This has happened several times in the past, so it's a good idea to have some sort of backup; all too many counties don't.
Union County uses 80 EMA for local operations. XCOEMA80 is the statewide interop channel. But the VHF repeater is used for countywide communications when they respond to an emergency scene. MARCS radios are too expensive to hand out to the 30-something members that are there.
Possible. But I suspect it's something different. Why in the world would they put up a repeater for tornado sirens. The would only need FB transmissions to accomplish that.
154.250 MHZ is still the tornado siren channel. Same as the fire paging channel.
Also, for anybody interested, DIRECT C is used for simplex analog fireground operations.
DIRECT C 856.5125 MHZ (CSQ)