An Ocean City firefighter has been suspended and faces charges of simple assault against his girlfriend that took place in December.According to the Press of Atlantic City charges against Jeremy S. Sullivan were filed Dec. 14, the same day as the incident. He is alleged to have assaulted his girlfriend about 5 a.m. that day.John Tumelty, Sullivan’s defense attorney, said Monday the alleged assault took place in her apartment in Ocean City.Sullivan, who makes $56,012 a year, has worked as a firefighter for more than two years, Tumelty said, and also works as a manager at Manco & Manco Pizza.