The city of Gainesville is suing Hall County over millions of dollars in special purpose local option sales tax payments that Mayor Danny Dunagan said the county owes the city. The civil suit asserting breach of contract was filed in Hall County Superior Court on Tuesday. The dispute is over the interpretation of a 2008 intergovernmental agreement between the city and the county that spelled out the percentage of SPLOST VI revenues the city would receive and how it would be paid out.