Two men guilty in Parker’s Lake pollution


Two men received fines and were placed on probation after a three-year investigation into the illegal dumping of industrial waste into a storm sewer that empties into Parker’s Lake in Plymouth near a swimming beach.

Alan Petersen (PDF), 51, of Osseo and Cory Tromp (PDF), 68, of Las Vegas, Nev. were each sentenced Aug. 29 to three years of probation after they pleaded guilty to the gross misdemeanor charge of violating water quality standards. Each man also was fined $4,000 by Hennepin County District Court Judge Daniel Mabley. In return for the guilty plea, the dozen other charges each man faced, including the felony unlawful disposal of hazardous wastes, were dismissed.

“This kind of reckless handling of hazardous wastes harms the public waters and had the potential to harm people swimming in Parker’s Lake,’’ Hennepin County Attorney Mike Freeman said. “We won’t tolerate that kind of behavior and thanks to the good work of Hennepin County’s Environmental Services Department and our prosecution staff, these two men have been punished and the illegal dumping has ended.”

An inspector from the Hennepin County Environmental Services Department first uncovered the violation in January 2010, during a routine hazardous waste inspection of the Progress Casting Group foundry in Plymouth, which was wholly owned by Atek. The inspector observed a 450-gallon plastic portable tank that Tromp, the maintenance manager, said was used to neutralize scrubber waste. The waste was then poured down a storm sewer drain in the company parking lot and Plymouth city employees said the sewer drains into Parker’s Lake near the swimming beach.

The company made molded aluminum products that required the use of triethylamine gas, which is flammable, corrosive and toxic. A scrubber captured the gas using sulfuric acid, and the spent scrubber solution is a corrosive and toxic hazardous waste. Records kept by the company showed that 1,950 gallons of the waste was dumped into Parker’s Lake from August 17 through October 29, 2009. Testing also found other hazard materials in that scrubber waste.

From 1990 to 2007, the company regularly disposed of the wastes properly by shipping them to a hazardous waste disposal company. The environmental inspector spoke to Tromp about the neutralizing tank. He said he poured in a caustic compound to raise the scrubber waste from an acidic 2 pH to a neutral pH and then poured the liquid down a storm water drain in the company parking lot.

During the investigation, a number of employees interviewed said there were discussions during morning safety meetings about how to handle the waste. Tromp and Petersen overruled other employees who wanted to continue shipping the waste off site to an authorized hazardous waste disposal facility.

However, Petersen had purchasing authority and began buying the compounds needed for the neutralizing effort and told Tromp to go ahead with their plan.

Tromp and Petersen told investigators that they thought neutralizing the hazardous waste would make it safe to put in the storm sewer. County officials determined that neutralizing it might have fixed the corrosive aspect of the waste but would not diminish its toxicity. The county also concluded that Tromp and Petersen should have known, based on proper disposal methods used by the company in the past and the discussions at the safety meetings, that disposal in the storm sewer was illegal and unsafe.