Officials are still trying to determine the origin of a strange substance found in Lake Michigan that shut down a Northwest Indiana beach on Monday.
Beaches in Northwest Indiana remained closed again Tuesday, not due to the mysterious substance, but because of the threat posed by rip tides and high waves. That gave investigators more time to look into where the mass of particles came from.
Officials say the unidentified floating object covered a 2-mile area and was first spotted off a beach near Porter, Indiana.
Brendt Baughman, park manager at the Indiana Dunes State Park in Chesterton, says he’s never had to evacuate and close the beach because of something like this.
“This is the first time in my eight years that we’ve ever had to close for an unknown substance,” Baughman said. “Besides one of the adjacent factories, it’s something that could have come out the air, it’s something that could have come off a ship. It’s too early for me to know and improper for me to speculate.”
Baughman says the substance looked like fine black sediment with some shiny, reflective material.
“It looked to be an inorganic material and did not seem to have a slimy appearance,” Baughman said.
He says it was first spotted around 2 pm. Monday near a beach in Porter that is partially private and also within the boundaries of the Indiana Dunes National Lakeshore. The substance was floating about 100 feet off shore when it was first spotted.
“The officials in Porter gave us a little time to evacuate our beach,” Baughman said.
Preliminary tests conducted by the Indiana Department of Environmental Management found some of the same chemicals used in fertilizers, but officials say it’s too early to know the exact source.
“We don’t have confirmation yet. Our investigators were out yesterday and were out again today,” says Dan Goldblatt, spokesman for the IDEM. “We hope to hear by the end of the week what it is. That way, it will give us a better idea of where it came from and if it poses any risks to the residents and visitors to the beaches.”
Goldblatt said early tests did rule out hydrocarbons as a culprit, meaning it is not an oil spill. Lab tests also found traces of tricalcium orthophosphate.
“We don’t know if that’s from a spill or was already in the water,” Goldblatt said. “The sheen was found at the shore yesterday. But when our investigators went out this morning (Tuesday) there was no evidence of it. We don’t know if it sank or was blown out into the lake.”
U.S. Coast Guard Seaman James Conner said a search helicopter looked for the shiny substance today but couldn’t find it.
“We’ve been looking for it. We also have people on site taking water samples but so far we don’t have specifics we can say,” Conner says.
Michael Puente is WBEZ’s Northwest Indiana bureau reporter. Follow him on Twitter @MikePuenteNews.