The installation of a new smokestack scrubber at RRI's Cheswick coal-fired power plant will reduce emissions of soot and sulfur dioxides by up to 98 percent, but it could result in as much as a four-fold increase in lead emissions, according to the Group Against Smog and Pollution.
The environmental group praised Allegheny County's biggest pollution source for reducing sulfur dioxide emissions, but questioned the need to allow lead emissions to increase to 1,810 pounds a year, the limit contained in a proposed installation permit modification that is open for public comment.
"It's incredibly misleading for RRI to spend years describing the scrubber as an environmentally friendly project and then turn around and try to slip in a permit change that would actually allow increased pollution," said Rachel Filippini, GASP executive director.
A county health spokesman said that the department agreed to increase the lead limit in the permit only after determining that such an increase would not affect the county's ambient lead levels which are 0.01 to 0.02 micrograms per cubic meter, well within federal air quality standards of 0.15 micrograms per cubic meter.
According to the federal Toxic Release Inventory, the 637-megawatt power plant emitted 0.23 tons, or 460 pounds, of lead in 2008.
Joe Osborne, GASP legal director, said the higher lead limit could allow RRI to change the mix of its power plant fuel to burn dirtier coal with higher lead emissions.
Laurie Fickman, a spokeswoman for RRI, said the lead limit increase in the permit modification is based on the scrubber manufacturer's "outer limit" for lead emissions.
"We're not trying to increase emissions. We want to correct them," Ms. Fickman said. "We are always looking at different sources of fuel, but we have no immediate plans to do that."
In 2006, RRI, formerly Reliant Energy, requested permission from the Health Department to conduct test burns of various mixes of Western Pennsylvania coal and Powder River Basin coal from Wyoming and Montana.
The power plant had no limit on the amount of lead it could emit until April 2007, when the county Health Department issued an installation permit for the flue gas desulfurization equipment, commonly called a "scrubber."
That permit, which allowed RRI to begin installation of the scrubber, contains an annual lead emissions limit of 0.315 tons, or 630 pounds, but RRI appealed, asking for the higher limit. The Health Department granted RRI's request and included the increase in the proposed permit modification now available for public review.
RRI has almost finished installation of its scrubber, a state-of-the art technology for major sulfur dioxide emitters like power plants. According to the U. S. Environmental Protection Agency, the technology uses a sorbent, usually lime or limestone, to remove sulfur dioxide from the gases produced by burning coal.
Sandra Etzel, the Health Department's air pollution control manager, said the new emissions controls should remove some of the lead along with the sulfur dioxides and particulates, but a change in the fuel could increase the overall lead emissions.
"We don't think it would lead to a violation of the ambient standard and if it would trigger a non-attainment ruling from the federal government and we'd be forced to look at the sources," said Guillermo Cole, the health department spoksesman.
But Mr. Osborne said the county lead standard level is based on measurements at just one monitor in Avalon, 20 miles from the power plant in Cheswick.
"I don't think the county can say with any certainty that because it has one data point we have nothing to worry about," said Mr. Osborne. "The Health Department hasn't done any modeling to determine the effect of such an emissions increase. And if it does increase by that amount, the Clean Air Act would require them to do modeling."
The public comment period for the proposed Cheswick power plant permit modification ends next Friday. A copy of the permit, identified in Health Department records as permit IP 0054-1004a, is available by calling 412-578-8191. Written comments can be mailed to the Allegheny County Health Department Air Quality Program, 301 39th St., Pittsburgh, PA 15201-1891, or sent via e-mail to firstname.lastname@example.org.
Don Hopey: email@example.com or 412-263-1983.