Blue Hole and Diver, Ichetucknee Springs, Florida, 1999Photograph by Wes C. SkilesA column of sunlight illuminates a diver in the diamond-clear waters of Blue Hole in North Florida’s Ichetucknee Springs State Park. Conservationists worry that Ichetucknee, one of the crown jewels of Florida's parks system, could become polluted by runoff far from the park's center.