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Mercury emissions are worse than CO2, but OK with the Supreme Court

If the Supreme Court wants a thorough economic analysis before permitting mercury controls, I suggest the chances are slim for court approval of billions for control of CO2.

A reduction in coal burning is in order.
REUTERS/Ina Fassbender

A new Supreme Court decision is restricting the Environmental Protection Agency’s ability to limit emissions of carcinogenic mercury, which results from coal burning. Where does that leave President Barack Obama’s Clean Power Plan? That plan is focused on limiting coal-burning emissions of carbon dioxide (CO2), an invisible non-toxic trace gas that is an essential plant food, and with dangers less certain than those from mercury.

The high court’s June 29 decision [PDF] focused on the EPA’s failure to do a cost benefit analysis of its regulation.

“It is not rational to impose billions of dollars in economic costs in return for a few dollars in health or environmental benefits,” Justice Antonin Scalia wrote in the majority opinion. The opinion remanded the case to a lower court for a further review into how costs should be considered in the EPA’s rule making.

Costs and benefits in dispute

The actual costs and benefits of mercury emissions and regulations are in dispute. The annual costs of compliance under the rule are generally estimated at $9 billion to $10 billion, but utility industry analysts estimate the annual benefits of reducing emissions of mercury and other hazardous air pollutants amount to only $4 million to $6 million.

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The EPA and environmental groups estimate the benefits to be at least $37 billion, a figure that includes costs related to an estimated 11,000 premature deaths and more than a half-million lost days of work each year. Sorting out this huge opinion difference will not be simple. It will be even more difficult when Obama’s Clean Power Plan attempts to restrict CO2 emissions from electric power plants, an even more expensive process than controlling mercury emissions. 

We humans have inhaled and exhaled CO2 with every breath since before Homo sapiens walked the earth. On the other hand, ingesting even a few grams of mercury is not recommended. If the Supreme Court wants a thorough economic analysis before permitting mercury controls, I suggest the chances are slim for court approval of billions for control of CO2, a trace gas that is one part in 2,500 in the earth’s atmosphere. 

Risks aren’t worth taking

Our industrial activity is emitting more than 30 billion tons of CO2 each year. John Abraham, thermal sciences professor at the University of St. Thomas notes that future consequences of global warming will include lower crop yields, especially in areas of subsistence farming; ocean acidification; redistribution of water; and more extreme weather, with fewer but stronger hurricanes. Although others disagree with these conclusions, the risks Abraham describes are not worth taking, and a reduction in coal burning is in order.

Rolf Westgard is a professional member of the Geological Society of America and is a guest faculty member on energy subjects for the University of Minnesota’s Lifelong Learning program

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Correction: An earlier version of this commentary incorrectly stated global temperature trends in the 21st century.