About a Market System for Mercury
By Jennifer Lee
New York Times
As the Bush administration presses ahead with a market-based
plan to let power companies swap their rights to emit
mercury, scientific and economic uncertainties leave an
important question unresolved: whether the plan would
leave "hot spots" with extremely high levels
of mercury around the country.
That question will be among those explored on Wednesday
at hearings in Chicago, Philadelphia and Research Triangle
Park in North Carolina, as the Environmental Protection
Agency moves to draw up mercury regulations for coal-burning
power plants by the end of the year.
Mercury emissions from coal-burning plants are not regulated
under federal law, though the Clinton administration had
moved toward strict regulation by classifying mercury
as a hazardous pollutant under the Clean Air Act in 2000.
Hazardous air pollutants, which include asbestos and lead,
are generally subject to strict controls at each source,
a requirement intended to bring down the level of pollutants
The Bush administration wants mercury to fall under a
less stringent section of the Clear Air Act that governs
pollutants like those that cause smog and acid rain, which
are not as toxic to humans.
Under the current proposal, power plants would buy and
sell the rights to emit mercury into the air; the administration
says this trading system is intended to cut mercury emissions
by 70 percent by 2018. Critics say that developing technology
will make it feasible to reduce mercury by 90 percent
on a faster timeline.
Environmental groups argue that mercury, a neurotoxin
that can harm fetuses and young children, should be subject
to plant-by-plant controls because it is acutely toxic
even at low levels and because it tends to concentrate
nearer its source than other air pollutants do.
According to the agency's own models, in-state sources
produce more than 50 percent of the mercury pollution
in 8 of the 10 states with the highest concentrations
"There are criteria for deciding which pollutants
should be traded, and should not be traded and mercury
fails most of these criteria," said Michael Shore,
who works with Environmental Defense, a group that has
previously backed pollutant trading.
Industry groups have sought a trading system, arguing
it is more efficient than uniform mandatory controls.
Industry and E.P.A. economists estimate that it would
cost $40,000 to $70,000 to remove each pound of mercury,
with the technology now available. Power plants emit about
48 tons of mercury annually.
Administration officials say that concerns about hot
spots are unfounded. "Based on the information we
now have, we don't think there is a concern on hot spots,"
said Jeffrey Holmstead, the E.P.A. assistant administrator
He noted that despite similar concerns, problems did
not arise after a sulfur dioxide trading program was created
by the 1990 Clean Air Act amendments to combat acid rain.
In fact, that system is widely considered a success by
both industry and environmental advocacy groups, reducing
the overall level of emissions ahead of schedule at a
fraction of the costs estimated when the proposal was
passed. Hot spots did not occur in large part because
the dirtiest power plants were the ones that had the greatest
incentive to clean up.
Environmental groups, though, say the most dangerous
areas for mercury are not necessarily the ones with the
dirtiest power plants since mercury enters the food chain
by converting into an organic form, called methylmercury,
as it falls into lakes and rivers.
Power plants produce mercury in two forms: a stable form
of elemental mercury that travels long distances and a
reactive gaseous form, which falls to earth faster.
"Hot spots come from high proportion of reactive
gaseous mercury," said David Krabbenhoft, a mercury
researcher at the United States Geological Survey. "You
wouldn't get hot spots with releases of elemental mercury."
Scientists and engineers say the reactive form of mercury
is easier to remove from power plants, which may address
some local concerns about hot spots. Another safeguard
is that states can impose their own controls.
"If states felt like they had vulnerable ecosystems,
they could opt out of a national trading program,"
said Robert Stavins, a professor of environmental economics
at Harvard's John F. Kennedy School of Government. Indeed,
while 43 states have advisories for mercury levels in
fish, only 14 of them, concentrated in the Great Lakes
region and the Northeast, have advisories covering all
state lakes and rivers.
Some believe the debate should be less on the appropriateness
of trading than on the overall limit and timeline. E.P.A.
staff and Democrats have endorsed hybrid controls that
combine trading with plant-by-plant controls.