INDIANA DUNES NATIONAL LAKESHORE: On Monday, August 12, 2013, the National Park Service (NPS) and the Environmental Protection Agency, Region 5 (EPA), began using sensing equipment to look for anomalies, gaps, and holes in the Mt. Baldy dune of Indiana Dunes National Lakeshore. This investigation is a follow-up to the rescue of Nathan Woessner from a hole that had developed in the dune in July.(Note to editors: the hole that led to the rescue was not a sinkhole and should not be referred to as a sinkhole).
During the course of the work investigators found a hole, approximately 10-inches in diameter, in the surface of the dune. The hole resembles the size and shape of the hole described by the Woessner family. The hole appeared to be 5-feet deep but may have been deeper as the sand at the bottom was very loose. The hole was not created by any human activity and is believed to have formed as a natural phenomenon. Samples of the sand and debris within the hole have been collected and will be analyzed.
Additional equipment will be brought to Mt. Baldy onWednesday, August 14, 2013, to collect sand samples from various depths within the hole, if it still exists, and areas near the location of the hole. The samples could provide the dates of the sand deposition under this area of loose sand.
The National Park Service has developed an investigation team comprised of NPS geologists and hydrologists and university researchers from several disciplines. The team will collectively make decisions about the progression of the investigation into the phenomenon associated with the conditions on Mt. Baldy.
The EPA conducted limited ground-penetrating radar (GPR) testing at Mt. Baldy on Monday, August 12, 2013 to initiate the park investigation. It is hoped that the GPR can provide a 3-D model of the dune (inside and out) as well as locate any anomalies within the dune that might require further investigation.
Additional testing and analysis of results will take weeks and the entire Mt. Baldy area will remain closed to the public until further notice. "We realize that many people would like to visit Mt. Baldy and we regret that the area is closed," said park superintendent Constantine Dillon, "but the fact that we do not know what caused the original hole, and that a new hole has spontaneously appeared, reinforces our concern that Mt. Baldy is not safe for visitors at this time."
Last updated: April 10, 2015