Hamilton County is probably too big (too many users) to go on the SAFE-T system. However, they could possibly convert to a Harris P-25 system. Aren't their radios P25 compatible? Other agencies have done that.
GTO_04
The vast majority of the radios are the newer models that can be firmware flashed/programmed into P25 service, but there is also equipment that would need to be changed out at the towers/back rooms. From the last report I heard, it is being investigated, but I do not know where the project stands now.
HamCo does have a lot of users on the network, but I wouldn't see an issue if HamCo had the tower coverage as well as the digital ID's to go with the network. Obviously there would be no way HamCo could go to Safe-T Analog due to the volume of users, but if they went digital, it shouldn't be an issue.
The other issue with Safe-T is the state owns it, and they can with a flick of a switch, shut your equipment off if the county got into a "who's bigger" fight with the state, whereas local established communications systems are owned and maintained by the county/towns/cities. Provides a little more control over who gets to turn stuff on/off.
HamCo would probably need at least 3 more Safe-T towers to ensure proper coverage. Just my opinion/thoughts. I am no way an educated person on radio theory/propagation but HamCo is currently a 4 tower system, and there is already 1 Safe-T site in the county, so adding three more should in theory work.