One Year Later -- Park Officials keep Mt. Baldy of Indiana Dunes Park closed indefinitely -- Woessner child only victim of mysterious "holes"

from National Park website: Despite the use of ground penetrating radar, and data gathering at two additional holes that have appeared since last July, scientists still don’t know the cause of the holes at Mt. Baldy in Indiana Dunes National Lakeshore. Additional research will be conducted this summer and may last into the fall. To ensure the public’s safety, Mount Baldy, its parking lot, trail, and beach in front of the dune will remain closed to all vehicular and pedestrian access while the investigation continues. “Mount Baldy is one of the most visited sites in the national lakeshore, attracting thousands of visitors each year” said Acting Superintendent Garry Traynham, “but the continued development of these holes in the dune surface poses a serious risk to the public. Our first obligation must be to the welfare of our visitors who are here for an enjoyable outing.” Ground penetrating radar studies by the Environmental Protection Agency (EPA), have identified a large number of anomalies below the dune’s surface, but analysis by scientists from the National Park Service, Indiana University and the Indiana Geological Survey have not yielded answers on how these holes form. One such hole nearly cost a 6-year old Illinois boy his life July 12, 2013 at the national lakeshore’s most popular sand dune. The two additional holes and a number of depressions have been found during the ongoing investigation and continued monitoring of the dune. Scientists report that the holes are short-lived, remaining open for less than 24 hours before collapsing and filling in naturally with surrounding sand. Scientists are now preparing for a more comprehensive investigation of the dune this summer. This study will include mapping of openings, depressions, and anomalous features, the use of multispectral Ground-Penetrating Radar (GPR) and coring to develop a better understanding of the overall internal architecture of the dune, and detailed GPR and coring of some of the anomalies identified in the EPA report. During the research work, the park’s resource managers will continue planting marram grass on portions of Mt. Baldy where the native dune grass used to grow. The extensive root system of the grass holds sand in place and may also help prevent holes from opening up on the dune’s surface.