Scientists from Purdue University Calumet and Argonne National Laboratory did a good job of studying the available technologies to prove that BP can indeed keep mercury out of Lake Michigan, easily complying with the Great Lakes Initiative standards.
The scientists worked on the project for more than four years before releasing their findings Tuesday in a community briefing at Purdue Calumet.
In the final analysis, it's not just whether a technology works, but whether it's cost-effective.
The scientists took into account energy costs for operating the technology, not just because of the operating cost but also to make sure burning coal to generate electricity didn't put more mercury into the air than was being removed from the water. That narrowed the options, said George Nnanna of Purdue Calumet's Water Institute.
The scientists tested two products at BP's Whiting Refinery. One was an ultrafiltration technology that uses fiber membranes to trap mercury. That technology kept the mercury levels at 0.5 parts per trillion, well below the U.S. EPA threshold.
Nnanna put this in perspective. One part per trillion is the equivalent of one drop of water in 20 Olympic-size swimming pools, he said.
"The bottom line is the technology was able to meet the limits throughout the test period," said M. Cristina Negri, Argonne's lead scientist on this project.
Also tested was a unit that uses ferric sand to filter mercury through precipitation, filtration and adsorption. That technology worked, too, when a chemical was added to the sand.
The ultrafiltration system's cost was somewhere between $39 million and $147 million, Negri said, while the other unit would cost between $20 million and $36 million.
Real world conditions would determine the actual cost of either installation. Operating costs must be figured in, too.
Whichever route BP takes, it will pay a bundle for this technology.
The Indiana Department of Environmental Management permit requires BP to commit to continuing investigation into emerging technologies but doesn't mandate implementing any of them.
One definite benefit already achieved from this research was the collaboration between Argonne and Purdue Calumet. The partnership was successful and should prove useful as a model for future research.
U.S. Rep. Pete Visclosky, D-Merrillville, arranged for the study, funded by a $5 million grant from BP, to help settle a dispute over BP's water discharge permit so the $3.8 billion expansion of Whiting Refinery could go forward.
That success story is worth noting.