I don't live in the area, but my understanding is that all public safety agencies in Jasper County use the Palmetto 800 system for communications. Based on the data we have in the RR database, it looks like Jasper Co Fire and EMS are in the clear, while all law enforcement, including municipal PDs are encrypted. This is consistent with what you've determined and what I have noted in the times I've visited nearby. It's possible that the fire department may still tone out on VHF, but I don't know that for certain. Otherwise, there probably isn't much conventional channel usage for public safety. Maybe there is for local government, public works, schools, businesses. You'll likely have to search those out for yourself.
I would guess that the dispatch center/PSAP location would be listed somewhere on the county government's website. Typically, smaller counties have consolidated dispatch centers that handle all public safety dispatching duties, but not always.
Due to the networked nature of the Palmetto 800 system, Jasper County talkgroups might be heard on sites other than the Jasper site. If you're not familiar with how networked trunked radio systems work, talkgroup activity on specific sites is determined by affiliation of the subscriber radios. A subscriber radio is the handheld or mobile radio that is carried by a public safety official. As that radio moves around, it automatically determines the site with the best signal, and the radio will affiliate with that site. If no radios are affiliated with a given site, that talkgroup won't be heard on that site. Most radios will likely affiliate with the Jasper site most of the time, so most talkgroups will be heard on that site most of the time. I have heard Jasper County talkgroups active on the Bluffton site, but not consistently. The same may be true of Limehouse. The only way to know is to listen, and note which talkgroups are active.
Based on FCC licensing data, the Jasper transmission tower is located here, which is near the intersection of Kato Bay Rd and Okeetee Fire Road. FCC licensing data is generally, but not always, 100% accurate. Note that the coverage area circles are estimates and aren't likely 100% accurate.
The Limehouse site is here, 8029 Speedway Blvd. It's a relatively new site.
The other sites that might carry Jasper County talkgroups are Hampton, Yemassee, and Port Royal. But I wouldn't bother programming sites that are out of your receiving range. How "far" you can hear is determined by your location, elevation, antenna system, the receiver you're using, etc.
