MICHIGAN CITY, Ind. -- A ground-penetrating radar survey found dozens of anomalies in a large sand dune along the Lake Michigan shoreline in northern Indiana where an Illinois boy was buried under 11 feet of sand last summer, but scientists still aren't sure what caused the dune to swallow the youngster.
National Park Service geologists are reviewing the report, which shows Mount Baldy at the Indiana Dunes National Lakeshore contains 66 anomalous spots where there's something other than pure sand beneath the dune, lakeshore spokesman Bruce Rowe said. Some of those spots are probably tree stumps or holes, but at least six of the anomalies are metal objects, he said.
"All national parks have some dangers within them," Rowe told WSBT-TV. "The thing that's different here with Mount Baldy is we really don't know what's going on so we really don't know what to warn people about."
The dune near Michigan City has been closed since July 12, when then-6-year-old Nathan Woessner of Sterling, Ill., was buried for more than three hours. The youngster survived and returned home after being hospitalized for about two weeks.
The report on the dune's composition was compiled by the U.S. Environmental Protection Agency, which used ground-penetrating radar last summer to inspect the dune after the boy's ordeal.
Scientists from all over the nation have scrutinized the dune to try to determine what created the apparent sinkhole.
Researchers with the National Park Service's Geologic Resources Division in Colorado are reviewing the EPA report and are expected to give their analysis to park officials by the end of February. They'll also make recommendations on additional research or testing to be done at Mount Baldy, a 126-foot high dune about 55 miles east of Chicago that's popular with park visitors.