MICHIGAN CITY, Ind. (WOWO): Crews are expected to start examining a northern Indiana sand dune for any problem areas similar to where a collapse last month buried a young Illinois boy under 11 feet of sand for more than three hours. The National Park Service and the Environmental Protection Agency are scheduled to use ground-sensing equipment starting today at the 43-acre sand dune called Mount Baldy at the Indiana Dunes National Lakeshore. That section of the park has been closed to the public since 6-year-old Nathan Woessner of Sterling, Ill., became trapped last month. Doctors initially put Nathan in a medically induced coma but he recovered enough to go home from a hospital two weeks later. Some geologists think a long-buried tree trunk decomposed under the dune and created the void.