Legacy pollution forces small town to look for new drinking water supply
About 10 years ago, a weird chemical started showing up in the drinking water in St. Louis, Michigan.
It was a byproduct of DDT. The insecticide is now banned in the U.S., but DDT was manufactured in St. Louis for 20 years.
Now, the city is working to get a new source of drinking water.
Becki Childs washes dishes with tap water, but she won’t let her family drink it.
"It looks fine. I mean sometimes in the past couple of weeks, it’s smelled funny," she says.
Childs lives about a block away from the old chemical plant site with her husband, Dan, and their three kids.
"The city tells us that they test the water quarterly and the water is safe for consumption," Dan Childs said. "But I don’t trust them as far as I can throw them so …"
Dan says they’ve been drinking bottled water for years, since tests revealed the DDT byproduct in the water supply.
Chemical breaches containment wall
The byproduct is called para-chlorobenzene sulfonic acid; pCBSA for short.
It is leaching from the old chemical plant that once made DDT. It’s not supposed to.
In the 1980s, the plant’s owners agreed to clean up the property. All that’s left of the plant was buried underground near the Pine River.
They constructed a wall around the perimeter and put a cap on top of the site. This was supposed to help contain the slurry of chemicals the plant used to make.
"But as the data came back, it became more apparent that there were breaches in the wall," said Scott Cornelius.
Cornelius was assigned to the site when he worked at the DEQ. He's now retired and consulting the city.
He says it looks like the chemicals ate through the wall.
"The cap, this clay cap that was on top, it was not preventing water from actually infiltrating into the site," added Cornelius.
Rainwater is getting into the site. Chemicals in the soil there that can dissolve in rainwater, like pCBSA, are.
"There’s like an open bottom basically that contaminants were flowing out into the groundwater. And that’s how the drinking water got contaminated here in St. Louis," Cornelius said.
When news of this water contamination came out in 2005, people in town were alarmed.
St. Louis resident Gary Smith remembers the schools provided bottled water for a little while. Inmates at a couple of the state prisons in St. Louis sued for the same.
But the panic subsided, and many people went back to tap water.
Health risks unknown
Gary Smith never stopped drinking it.
"I like it. I cook with it, clean with it, drink it, and have been doing so for 63 years," he said.
Smith and I gulp down some water from his tap, because no one says the water is not safe, even with the pCBSA.
We don’t know a whole lot about the human health risks.
Federal regulators don’t have an established limit for drinking water.
State regulators mention a couple of rat studies to determine their level, 7,300 parts per billion.But tests of St. Louis’s drinking water show levels of pCBSA are way, way below that level. In 2013, the highest level measured was 73 parts per billion.
But the big concern is not the pCBSA.
If this chemical found its way from the old plant site to the drinking water, much more harmful chemicals could too.
"If it found its way through the geology, something else will. And when will the bad stuff get there is the $64 question," Smith said.
But the city and environmental regulators hope the “bad stuff” won’t ever become a problem because the city has found a new drinking water supply, and there’s a new plan to clean up the old plant site.