Yes, all local public safety communications are on Palmetto 800. All Charleston County LE and municipal LE traffic is encrypted. Make sure to pay attention to the names of the Palmetto 800 sites - Site 1-10 Charleston Simulcast (County) will carry all county public safety agencies (fire, EMS. encrypted LE) and local government agencies (water and sewer, parks&rec, etc). You'll also hear SC Highway Patrol for Charleston County in the clear on this site. Site 1-9 also covers Charleston County but handles traffic from other state agencies (DHEC, EMD, MUSC Hospital) along with SCHP. It also carries some Berkeley County and Dorchester County radio traffic. You may want to program your radio in a way that you scan both of these sites simultaneously.
As for other systems, I think the database is pretty accurate. If you have the DMR entitlement for your radio, there are few different DMR trunked systems (Charleston Wireless, Palmetto TRBO, etc). to monitor that carry radio traffic for various businesses. One site of the Palmetto TRBO system carries a lot of traffic from the SC Ports Authority terminals. There are a couple of different trunked systems related to utilities (the P25 system for SC PSA being the most notable). Joint Base Charleston is a combination Air Force Base and Navy base north of Charleston that operates a P25 system - this system may be a little out of reception range from the Peninsula. Conventional-wise, there will be plenty of marine radio traffic, local business traffic, and probably some federal traffic. And plenty of amateur radio activity.
Hope that helps. Enjoy your visit.
