HAMMOND | Lab tests show three technologies are effective at reducing mercury and other pollutants from wastewater discharges into Lake Michigan, and more work is under way to test them on a broader scale, researchers said Tuesday.
Scientists from Purdue University Calumet's Water Institute and Argonne National Laboratories in Argonne, Ill., presented the findings of their study at a community briefing Tuesday morning at Purdue Calumet.
"Here we have seen industry, universities and the national laboratory come together to find a common solution to a common problem," said Dr. George Nnanna, of the PUC Water Institute and co-lead scientist of the project. "There is hope to improve the health and quality of water in Lake Michigan."
The study, funded by BP, began in the fall of 2007, a year after BP's Whiting Refinery announced a $3.8 billion modernization plan aimed at retrofitting the 120-year-old facility to accept more heavy crude extracted from Canadian oil sands.
The sands contain a host of metals and other pollutants, presenting a challenge when meeting federal Clean Water Act requirements for discharges into Lake Michigan.
In the lab, 21 researchers found ultrafiltration, adsorption and reactive filtration to be the best of the more than 50 technologies studied for removing particulate mercury and dissolved mercury. The goal was to find technologies to reduce the pollutants to below 1.3 parts per trillion in samples.
M. Cristina Negri, of Argonne National Laboratories, who served as co-lead scientist of the project with Nnanna, said finding three technologies to meet the 1.3 ppt standard was significant because the researchers doubted it was possible.
"There is no prohibition to achieving that goal," Negri said.
Pilot projects are under way at the Whiting Refinery on two of the technologies while the third is being studied further in the lab.
"We're trying to see if what we found at low scale is still true with a larger scale," Negri said.
The latest round of testing is set to conclude in December.
"This is not just good for industry; it's good for the community," Nnanna said. "This can serve as a foundation for future studies."
John Veil, of Argonne National Laboratory, presented findings of a study comparing nonpoint sources of pollution in Lake Michigan and point sources. Nonpoint sources include stormwater runoff and air pollution from coal-fired power plants, and point sources are specific industrial businesses or wastewater treatment plants.
For the study, Veil drew from other studies of regional areas, not Lake Michigan, and found ratios as high as 112 to 1 for nonpoint source pollution to point source pollution for mercury.
Veil acknowledged the nonpoint source information came from studies not related to Lake Michigan. The information, he said, is scarce and questionable.
"There is quite a bit of uncertainty in those data sets," he said.