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In case you’re new in town, three and a half years ago an Enbridge pipeline broke, causing a huge oil spill near Marshall, Michigan.

The case of the mystery rocks

A couple of years ago, I met Craig Ritter while doing some reporting on the river cleanup.

He’s your typical, passionate, Michigan out-of-doors type.

He says he was out fishing last summer.

“I started noticing these weird formations that I’d never seen before,” Ritter said.

Ritter found dozens of round, porous, rock formations, some of them nearly as big as a bowling ball.

“I picked it up. It was really light, and it almost crumbled in my hand. When it crumbled in my hand, part of it fell in the water kind of – left a real light sheen,” Ritter said.

He was curious. So he sent some photos to regulators and scientists.

Steve Hamilton, a professor at Michigan State University and president of the Kalamazoo River Watershed Council, saw the photos. Hamilton says they’re just regular, calcium carbonate, tufa rocks you find all over the place.

“They posted very good photos. I recognized immediately what they are because I actually dig those up and show them to my students and they’re not uncommon in southern Michigan waters,” Hamilton said.

But Ritter wasn’t so sure. Yes, he says, some of them look like tufa rocks, but they crumble too easily. He brought some into pet stores where tufa rocks are sold for fish tanks, and he says they weren't convinced the rocks were regular tufa, either.

I’ve been trying to get a second opinion on the rocks, but my attempts have not been completely conclusive.

One lab’s surprise results make mystery rocks seem even more mysterious

Ritter and some friends sent a sample of the rocks to an independent lab in Alabama to be tested.

The lab said the mystery rocks had oil from the spill on them – no big surprise. Workers are still cleaning up what’s left of the oil on the river bottom.

The big surprise – the chemist at this lab, Robert Naman, says there was evidence of a surfactant that was used in the BP oil spill in the Gulf of Mexico, too.

Surfactants help break down oil during oil spills.

But Enbridge officials, and state and federal regulators are adamant. They say no surfactants were used in the Kalamazoo River oil spill.

Many media outlets have run with the story, even without having the lab results in hand or a second opinion.

Some have reported that a second lab in Massachusetts had concurred with Naman’s opinion. But the chemist at that lab, Dave Kahler, says he only concurred that the Kalamazoo River water sample, a mystery rock sample, and a sample of oil from the 2010 Enbridge spill match one another.

So this is just one lab’s results that claim to show evidence of surfactant use.

While they certainly warrant a look, a second or third opinion is needed. I’ve got a few chemists looking into the tests from Alabama to see if they can somehow confirm the results.

The case of the mystery signs

Okay, let’s go back to Craig Ritter, exploring the Kalamazoo River.

Last September he finds two separate signs partially buried in the mud near the spill site.

The signs warn people not to swim, irrigate crops, or feed livestock because there have been some chemicals used in the area. The signs look only partially filled out, so it’s not clear how long people are being instructed to be cautious.

One of the chemicals listed on the sign he finds is a surfactant. Ritter cannot help but jump to some conclusions here, especially after what the chemist in Alabama had just told him.

“From the beginning of this spill we’ve had so many unknowns. Here we are three and a half, going on four years later, and we still got unknowns. There’s just more questions, and it’s the unknown, it’s the fear of the unknown, that we have,” Ritter said.

But wait, whoa, back it up a second, Ritter.

At least, that’s the impression Brad Wurfel gives when talking about these conclusions. Wurfel is a spokesman with the Michigan Department of Environmental Quality.

“If you and I took a walk along the Kalamazoo River, and we found a roll of duct tape, and a banana peel, and a paper clip, you might want to tell me a story about how all these things are connected. But in fact they’re just a banana peel, a roll of duct tape, and a paper clip that happen to be down by the river,” Wurfel said.

Wurfel admits that together, to a layperson, these things could look concerning. But he says the mystery signs and the mystery rocks are not directly connected.

The signs are actually a whole lot easier to explain.

The wetland areas near Talmadge Creek, that were hit the hardest by the oil spill, had to be completely dug out and remade. That set the stage for invasive plants to take over. Wurfel says Enbridge was ordered to take those plants out as part of the restoration effort.

“They do that using an herbicide and they mobilize that herbicide, in a lot of cases with surfactants, small amounts of them,” Wurfel said.

Super small amounts of surfactants. A report that came in this week shows crews used less than two gallons of surfactants on 18 acres. It’s a common practice in fighting invasive plants and it is allowed under state permits.

So mystery signs? Solved.

Mystery rocks? Well, when I get some answers, I’ll be sure to give you an update.