Friday, October 10, 2008

Wisconsin Finalizes 90% Reduction Rule; Univ. of Michigan Researchers Discover Mercury Fingerprinting Technique

Wisconsin
The State of Wisconsin, known as a haven for fishermen, has taken steps to see that that reputation remains intact. They become one of only a handful of States to pass tough mercury legislation requiring a 90% reduction in mercury emissions by 2015. A state regulation proposed by the Natural Resources Board will go into effect January 1, 2009.

Some excerpts from a Capital Times article follow;

The rule will require a reduction in the amount of mercury sent into the environment by coal-powered power plants by 90 percent by 2015. Coal plants are a major producer of the toxic substance.

Under the rule, those plants also have an option of moving the full mercury reduction target back to 2021 if sulfur dioxide and nitrogen oxide are reduced before then.

"DNR Secretary (Matt) Frank can sign the rule Tuesday morning, and it will be delivered immediately to the Legislative Reference Bureau for publication. It would likely be effective December 1, and January 1 at the latest, depending on when it is published," said Paul Heinen of the Department of Natural Resources.
[...]
Rep. Spencer Black, D-Madison, declared victory after a long fight to cut down on mercury emissions. He first filed a legal petition for rules to limit mercury emissions in May 2000, along with 12 environmental and fishing groups.

"Today is a great day for those of us who love the outdoors, especially all the residents and visitors to Wisconsin who love to fish or to eat fish," Black said. "Almost every lake in Wisconsin is under warning for mercury pollution. This rule will ... help to clean up our valuable water resources."
[...]
"Governor Doyle promised to work for a 90 percent reduction in mercury emissions, and he has kept that commitment," Black said. "
[...]
Business organizations including Wisconsin Manufacturers & Commerce, Wisconsin Utility Investors and the Wisconsin Paper Council tried unsuccessfully to obtain a court order blocking the rule before the board acted, saying the DNR did not adequately define the scope of the rule. A Dane County Circuit Court judge dismissed the lawsuit.

U of M Mercury Fingerprinting
Excerpts from an article from PhysOrg.com summarizes as follows;

Oct 8, 2008 - (PhysOrg.com) -- University of Michigan researchers have developed a new tool that uses natural "fingerprints" in coal to track down sources of mercury polluting the environment. The research is published in today's online issue of the journal Environmental Science & Technology.
[...]
"There has been a lot of controversy about how much mercury is coming from different types of industrial activities, compared to natural sources, but it has been difficult to figure out the relative contributions," said co-author Joel Blum, the John D. MacArthur Professor of Geological Sciences and a professor of ecology and evolutionary biology. "And even if you can determine how much of it is coming from natural versus human sources, there's still the question of how much is from global sources, such as coal-fired power plants overseas, and how much is being produced and deposited locally."
[...]
"For some time, we weren't sure that it was going to be technically possible, but now we've cracked that nut and have shown significant differences not only between mercury from coal and, say, metallic forms of mercury that are used in industry, but also between different coal deposits," Blum said.

The fingerprinting technique relies on a natural phenomenon called isotopic fractionation, in which different isotopes (atoms with different numbers of neutrons) of mercury react to form new compounds at slightly different rates. In one type of isotopic fractionation, mass-dependent fractionation (MDF), the differing rates depend on the masses of the isotopes. In mass-independent fractionation (MIF), the behavior of the isotopes depends not on their absolute masses but on whether their masses are odd or even. Combining mass-dependent and mass-independent isotope signals, the researchers created a powerful fingerprinting tool.

Previously, Blum and coworkers investigated the possibility of using the method to identify sources of mercury contamination in fish. The coal project was more challenging because of the difficulty of extracting and concentrating mercury from coal. The researchers developed a system that slowly burns the coal under controlled conditions in a series of furnaces and then traps the mercury that is released.

More work is needed to perfect the fingerprinting technique, but Blum envisions using it in a number of ways to track mercury and assess its environmental effects.
[...]
"Scientists have models and other ways of estimating how much mercury will be deposited locally, but we may, for the first time, be able to directly differentiate between mercury coming from local plants and mercury that has been transported longer distances."

In a project already underway, Blum's research group hopes to pinpoint which of the many mercury sources in the San Francisco Bay area are contributing most to the contamination of fish and wildlife.

"We don't know whether particular sources of mercury are more biologically available than others and thus more likely to accumulate in animals," Blum said. "If we can figure that out, then we can help local agencies decide where efforts will be most productive in terms of preventing wildlife from being exposed to mercury."
[...]
Blum's coauthors on the Environmental Science & Technology paper are two former postdoctoral fellows, Abir Biswas and Bridget Bergquist; Gerald Keeler, director of the U-M Air Quality Laboratory; and Zhouqing Xie of the University of Science and Technology of China. The researchers received funding from the National Science Foundation, the University of Michigan and Sigma Xi.

Maybe someday we will be able to tell exactly which plant is responsible for which local mercury pollution. Many plants burn coal from the same geologic deposit like the Powder River Basin (PRB) in Wyoming. But by refining and improving this technique, adding source spiking for instance, who knows how specific the detection methods will become.

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