MICHIGAN CITY, Ind. Crews from the EPA and National Park Service began examining a Northern Indiana sand dune for potential problem areas similar to where 6-year-old Nathan Woessner was buried under 11 feet of sand for more than three hours.
For the past month, the area surrounding the 43-acre sand dune, Mt. Baldy, has been closed off to the public. Several geologists theorized that a long-buried tree trunk decayed beneath the dune and created the void that Woessner fell into, but no physical investigation started until Monday.
Chicago criminal investigative units facilitated the ground-sensing equipment and personnel used by the EPA. The special ground penetrating radar is about $30,000 per unit in addition to $5,000 for GPS.
EPA Region 5 spokesperson, Francisco Arcaute, explained that the device takes ultrasound photographs from some 30 feet below the surface.
“It allows us to get an idea of what’s underneath the surface without damaging the top of the dune,” Arcaute added that it is the same equipment used in both criminal investigations and hazardous waste investigations to locate things like trailers, drums and even storage tanks hidden underground.
If the EPA finds anything abnormal or different than what’s expected, then it’ll take additional measures and bring in other specialized equipment to determine what exactly it is.
Monday crews began pushing the device in parallel lines across the dune. Law enforcement specialist for the Indiana Dunes National Lakeshore, Ken Mehne, said they’re using old photographs to determine where to start their search.
The park has been around since the 1960s and the living dune has consumed old boardwalks and trees as the sand erodes. Mehne explained that a restoration project has been going on for several years to slow down the rate of movement by planting dune grass.
But when the trees and vegetation die off, Mehne said there will be nothing keeping the sand and the dune from moving around. At one point there were houses along the dunes, however continual erosion makes the ground unstable.
There is still a conductivity to be done, said Supervisory Park Ranger Bruce Rowe, and until all the data is in, he and the EPA cannot offer anything but speculations.
Mehne added, “This is going to depend on what the data reveals, again there's not a lot of history or scientific data on this type of situation and I think it's going to take some evaluation once all the data is collected to determine what type of action to be taken at that point.”
The investigation into the hole that trapped Woessner started the day after the rescue, July 13, and since then the National Parks Service has filled in the hole, including the decayed tree material found inside.
According to Rowe, until they determine what mechanism caused the hole—or any other hole for that matter—the dune will remain closed to the public. Rowe did say that there has been a lot of evidence of trees being covered by dunes in the past, “so we figure if it is trees decaying we’ll probably find evidence somewhere else.”
After the initial accident, rangers have heard from two individuals regarding similar holes.
The first was from a man who said he was walking along Mt. Baldy within the last several years and stepped into a hole which went up to his mid-thigh. The caller said he didn’t report the incident because he wasn’t hurt.
A second individual reported a similar hole to the one described to have trapped Woessner in a private dune in Southwestern Michigan.
”Depending on what's found with their investigations, then it'll be the next step. I truly don't know what the next step is until we get through this one,” said Rowe.