The state sets limits on the levels of toxins that can be used on roads, but brine applied by Team Services this year to at least two dirt roads near Lake Ann in Benzie County tested a thousand times above allowable limits for toxins.
In some ways, the DEQ's Heuer said, that incident could serve a public purpose. Benzie County Road Commission officials took a random sample of liquid from the truck prior to road application -- though test results came in afterward -- which subsequently provided good data for the road commission and state regulators.
"This is an opportunity to speak with the industry and resolve some of the problems with (brining)," Heuer said.
DEQ and Team Services officials said they can't figure out exactly where the toxic liquid originated. The liquid that ended up on Benzie County roads was pumped from a storage tank in Manistee County, but public records show all of the wells where the brine came from were tested and approved for brine in 2013.
Bryan Black, a Lake Ann farmer, discovered and reported the Benzie brining incident in June. He said he and his wife Karla aren't satisfied with the state's probe, and they want someone to pay for continued testing of water wells on affected properties, among other concerns. Officials acknowledged that roughly 3,000 gallons of toxic liquid were spread on dirt roads near their property, but Black questions whether that figure should be higher, since the tanker trucks hold more than 6,000 gallons.
They also want to know what happened to the rest of the brine in the Manistee County storage tank that holds 8,000 gallons.
Rick Henderson, field operations supervisor for the DEQ's Office of Oil, Gas, and Minerals division, said the quick part of the investigation is over and remaining tasks will take time to complete.