Coal ash spill poses no health threat, DNR says
DNR tests find sufficient dilution at Oak Creek site
Tests of coal ash and Lake Michigan water samples collected after the Oct. 31 bluff collapse and coal ash landslide at We Energies' Oak Creek Power Plant found no significant threat to public health or safety, state Department of Natural Resources officials said Friday.
Even coal ash that might have washed ashore south of the power plant on beaches in Racine County is so diluted and dispersed that it would not harm someone touching the material, said Ann Coakley, director of the DNR's waste and materials management bureau.
"While having coal ash get to Lake Michigan is certainly a cause for concern, the amount of environmental risk in this situation is small," said Lloyd Eagan, DNR water leader for southern Wisconsin.
"Water quality at the spill site is close to the normal water quality of Lake Michigan," Eagan said. "Outside the spill site, the water quality is normal. There will not be long-term impacts to the aquatic environment once the spilled material is removed."
Test of water collected close to shore within a floating containment boom found levels of iron and aluminum only slightly higher than normal concentrations in the lake, according to Eagan.
There is a low risk of public exposure to the ash in the water since no one is swimming this time of year and the contaminants have not been detected at either the Oak Creek or Racine drinking water treatment plants, Eagan said. Though routine currents flow south along the shore and would more likely carry ash suspended in the water toward Racine, treatment plant operators there are confident filters can remove all the particles, Coakley said.
Much of the ash appears to have settled on the lake bed near the landslide. Test of ash in the bottom muck found toxic heavy metals, such as arsenic, cadmium and copper, at concentrations that could harm worms and other small aquatic life exposed to it over several years. But the ash will be dredged from the lake and aquatic life will resettle the area, according to Coakley.
Tests confirm that the coal ash is not hazardous and can be disposed of as a solid waste at lined landfills on the We Energies' property, she said. The ash does not have to be hauled to a special hazardous waste disposal site, Coakley said.
The landslide pushed an estimated 2,500 cubic yards of coal ash and soil into Lake Michigan. The slide carried 25,000 cubic yards down the slope, and about 10% of the load made it to the lake.
The mix of ash and soil came from a ravine that had been filled in the 1950s. Water from a hilltop unlined storm-water retention basin might have seeped into the ravine and saturated the ash, according to geoscientists. Ash oozing out of the bottom of the ravine likely caused the top of the bluff to collapse.
The cause of the collapse remains under investigation, according to We Energies.
Mud and ash cascaded more than 300 feet down the slope to the shore.
No worker was injured.
The landslide occurred immediately south of a $900 million air pollution control facility under construction at the power plant. No damage was done to that structure.
Barge begins work
On Friday, a barge began pulling pickup trucks that fell down the slope and landed on the rocks by the edge of the lake. In addition, crews used a crane to remove a front-end loader that fell into the lake, We Energies spokesman Brian Manthey said.
Work to remove more equipment and beams that fell into the lake will continue over the weekend and next week, he said.
The utility is also working with the DNR and Coast Guard on a plan to recover coal ash and soil that have washed ashore south of the power plant, Manthey said.
In addition, at the top of the hill, adjacent to where the bluff gave way, workers began the process of removing empty ammonia storage tanks, Manthey said. Utility tests showed the foundation for those tanks has not budged since the collapse, but the utility decided to move the tanks out of concern for the safety of workers handling the cleanup of ash and debris on the slope, Manthey said.
The tanks were built to supply ammonia, which will be used to help scrub pollutants that would otherwise go up the power plant's smokestack. No determination has been made yet as to where on the power plant site those tanks and piping system will be rebuilt, he said.
The Sierra Club this week took the first step toward suing We Energies for violations of state environmental laws in the bluff collapse and discharge of coal ash to the lake.
The group's notice of intent to sue alleges that the pollutants in the coal ash now in the lake "pose and imminent and substantial endangerment to human health and the environment."
After the test results were released, Manthey said the DNR tests demonstrate there was no threat to public health or safety.
We Energies is asking lakeshore residents who find tools or other debris washed ashore to call a hotline. The hotline number is (877) 380-0522.