- You'll find convenient dump stations near Greenbrier, Arkansas RV Rentals for dumping black and gray water and filling up fresh water.- Several locations offer a hose for flushing tanks, as well as trash bins for waste disposal.- Some of the well-known dump stations around Greenbrier include Conway KOA Journey, Petit Jean State Park, Woolly Hollow State Park, Lake Dardanelle State Park, and Pinnacle Mountain State Park. - Please note that some of these dump stations may have a small fee or require a parking pass for access.