There's a reason the Southland Health Fair is in its 35th year, according to Susan Fine, who has been involved in the event from the beginning."It's the breadth and quality of service," she said. "Half of the people every year are those who come back year after year. The other half are brand new to the event, those who have heard how much you can get done in a day."The event, sponsored by UChicago Medicine-Ingalls Hospital, will take place from 9 a.m. to 1 p.m. Saturday, May 5, at Matteson Community Center, 20642 . . .