After conducting research, it appears that there is indeed a boat ramp named Clarendon County in South Carolina. It is located at 1070 Lake Marion Rd, Vance, SC 29163, with a latitude of 33.51506042 and a longitude of -80.18503571.

According to the South Carolina Department of Natural Resources website, Clarendon County Boat Ramp is a concrete ramp that provides access to Lake Marion. It is reportedly a single lane ramp that is 15 feet wide and can accommodate small and medium-sized watercraft, including boats, canoes, and kayaks.

Lake Marion is a large freshwater lake that covers almost 110,000 acres in South Carolina and has an average depth of 14 feet. It is a popular destination for boating, fishing, and other recreational activities.

In terms of regulations, the South Carolina Department of Natural Resources states that all watercraft operating on Lake Marion must be registered and have the proper safety equipment, including personal flotation devices (PFDs) for all passengers. Additionally, there may be certain restrictions on the use of motorized watercraft, depending on the specific area of the lake.

Overall, it appears that Clarendon County Boat Ramp provides convenient access to Lake Marion for a variety of watercraft. However, it is always important to check the latest information and regulations before heading out on the water.