A recent mudslide that swept tons of coal ash and debris into and around Lake Michigan probably will have little effect on the environment and none on human health, the Wisconsin Department of Natural Resources said Friday.
Test results show elevated levels of several elements in the coal ash still on land and in the water, two DNR officials said. But the contaminants are confined to areas not accessible to people and the chemicals can be cleaned up and safely disposed of, the officials said.
Their comments were based on a report released to the DNR this week by the U.S. Environmental Protection Agency. The EPA found slightly elevated levels of arsenic and chromium in the land-bound ash, while water samples tested slightly higher for iron and aluminum. Onshore sludge contained higher levels of arsenic, iron and nickel.
Coal ash has arsenic, selenium, lead and mercury in low concentrations. But like many other types of energy waste _ such as drilling muds _ it's not classified as hazardous under waste laws.
For that reason, the spilled ash can be removed safely and taken to a lined disposal site, said Ann Coakley, director of the DNR's waste- and materials-management program.
The mudslide occurred Oct. 31 when a section of cliff gave way on the grounds of a We Energies coal-fired power plant near Milwaukee. The collapse created a mudslide that sent a pickup truck and other equipment tumbling into Lake Michigan, swept several construction trailers toward the beach and left a swath of soil, ash and debris as large as a football field. There were no injuries or power disruptions.
The DNR estimates about 2,500 cubic yards of ash, or enough to fill about 200 dump trucks, may have reached the water.
Lloyd Eagan, a DNR water specialist, said there's little environmental risk from the debris that ended up in the lake. The spill happened well away from pipes that draw in drinking water for surrounding communities, she said, and the area has been blocked off so it's inaccessible to the public.
Eagan said some chemicals in the water could harm worms and bugs in bottom sediments if the contaminants were allowed to remain for years. If the chemicals are cleaned up quickly, the risk would be minimal, she said.
"We will require that they (We Energies) remove it," she said. "We don't expect any long-term impacts after that."
We Energies is working with the DNR and the U.S. Coast Guard on a plan to finish the cleanup, spokesman Brian Manthey said. Utility officials believed from the start the spill wouldn't jeopardize public safety, he said.
"The test results verify that," Manthey said.
Jennifer Feyerherm, a Sierra Club representative in Madison, said no reliable conclusions could be drawn about environmental effects because no samples were taken from sediments on the lake floor.
"Without looking at the bottom of the lake, they don't know what's there and what needs to be cleaned up," said Feyerherm, whose organization this week filed notice of intent to sue We Energies in federal court over the spill. "Heavy metals in coal ash tend to hang in the sediments more than the water."
Future testing will include sediment analysis, Coakley said.
Joel Brammeier, president of the Alliance for the Great Lakes, said he was encouraged that there weren't elevated levels of more serious contaminants. Still, he said the incident was a sobering reminder of the lakes' vulnerability to coal ash spills and other pollution.
"There are dozens of coal ash dumps out there that may or may not be leaching into freshwater supplies, that may or may not be failing, that may or not be ready to slump into another Great Lake," Brammeier said. "Right now, EPA doesn't have the tools to determine which of those fills is of greatest concern."
The DNR appears to be taking the right steps by ordering a thorough cleanup, said George Meyer, executive director of the Wisconsin Wildlife Federation.
"You don't want this to get into the water and stay in the water," Meyer said. "But they'll be able to get the majority of this out and I assume the rest would be relatively diluted."
Gary Fahnenstiel, senior ecologist with NOAA's Great Lakes Environmental Research Laboratory in Ann Arbor, Mich., said the contamination likely would affect only the immediate spill zone. Dredging of tainted sediments should keep long-term effects to a minimum, he said.
Michigan officials have no concern that the contamination will spread to the other side of the lake, said William Creal, chief of the Michigan Department of Environmental Quality's water resources division.
We Energies has said the cause of the cliff collapse remains under investigation.
Flesher reported from Traverse City, Mich.
Dinesh Ramde can be reached at dramde(at)ap.org.