UPPER THUMB — Ominous black spots on wind turbines in the Thumb have raised a few eyebrows.
Huron County Building and Zoning Director Jeff Smith says residents have questioned what look like grease stains on six or seven turbines between Sebewaing and Owendale.
“It was disturbing to see that,” Smith said, adding he drove through the area Monday.
Seals on the turbine were coming out of bearing holders, Smith said, comparing it to a vehicle with a bad wheel bearing. He said he’s not sure if the bearings on the turbines are faulty or defective.
“GE knew but did not tell us,” Smith said of turbine manufacturer General Electric, adding he got an email from NextEra Energy stating a cleaning crew is coming.
There are 32 turbines in Exelon Wind Generation’s Harvest 1 project in Oliver and Chandler townships. A 400-foot, 485,000-pound turbine that fell on Feb. 25 spilled 25 gallons of greases, oil and coolant, according to the DEQ (http://bit.ly/1TVboJD). The spill posed “no imminent drinking water or environmental health threat,” a DEQ official told the Tribune.
Exelon says the fallen turbine held about 400 gallons of oil.
The leaks aren’t limited to just Huron County.
South of Minden City, some of DTE Energy’s 20 turbines are planted in organic farm fields. A landowner on Charleston Road who farms about 1,000 acres said in February the Environmental Protection Agency and Michigan Department of Environmental Quality arrived about six months back when oil was leaking from a turbine’s nacelle, which encases inner components and is where the rotor attaches, but that oil did not leak onto the field.
Reports from the Coast Guard’s National Response Center for 2016 show a caller on Feb. 24 stated the turbine near Charleston Road was leaking oil onto the ground. The report shows an “unknown amount” of hydraulic oil and grease leaked. It didn’t cause injury, damage or road or waterway closings, but an “N” appears in an entry for “RELEASE_SECURED” and the report states an environmental impact to vegetation. The report gives no description for remedial action and says the EPA was notified.
Jennifer Wilt, lead communications specialist at DTE, says the utility currently has one turbine experiencing an oil leak. The cause is typically blade bearings, according to DTE.
The utility has established a process for notifications, remediation and cleanup of oil leaks, Wilt said.
“Through our environmental management practice, we do not have any concerns for landowners or the general public as the result of an oil leak,” Wilt said in an email. “Turbines are designed to contain oil leaks within the tower itself.”