Last week, the Environmental Protection Agency proposed new regulations governing emissions of mercury and other toxic air pollutants from power plants. This rule has been a long time coming. In the waning moments of the Clinton Administration, the EPA made a finding that would trigger mercury emission controls on power plants under the Clean Air Act. The finding had been in the works for some time, but the Clinton EPA had been reluctant to pull the trigger until December 2000. The Bush Administration did not appreciate the house-warming gift, and tried to undo the Clinton Administration’s handiwork with an alternative approach. They first tried legislation, but when Congress wouldn’t bite they pushed through regulations. The only problem was that the Bush EPA disregarded the Clean Air Act’s plain text in the process, earning a well-deserved rebuke from the U.S. Court of Appeals for the D.C. Circuit. The new rules, once finalized, may well trigger litigation, but I doubt we’ll see the same result. From what I’ve looked at so far, this is a fairly traditional regulatory approach.
This EPA fact sheet gives some background on the rule, stressing the anticipated reductions of mercury emissions. What the fact sheet does not mention is that, the lack of meaningful federal mercury controls notwithstanding, mercury emissions have declined since 1990. As the EPA’s Report on the Environment shows between 1990-93 and 2005, mercury emissions declined by 58 percent. Coal-burning facilities — which are covered by the new rule — represent the lion’s share of the rest.
The emission trends are positive. So, too, are trends in blood mercury levels. As the same EPA report shows blood mercury levels in women have declined, particularly among those at the 90th and 95th percentiles. From the EPA report: “during the 1999-2000 survey, 10 percent (i.e., 90th percentile value) of surveyed women age 16 to 49 had blood mercury levels of 4.9 µg/L or higher. In the 2007-2008 survey, however, the 90th percentile value had decreased to 2.7 µg/L.” That’s a significant drop for those with among the highest levels in the country.
These positive trends do not mean additional mercury controls are unnecessary, but it does put their urgency in perspective. It also suggests that the Bush Administration’s approach, which would have utilized a more flexible cap-and-trade approach instead of facility-specific limits, may have been good policy after all, even if it was horribly bad law.