State grapples with mercury

Regulators, industry at odds with cities, activists over rules

Colorado's plan to curb mercury pollution from coal-fired power plants, which account for about 40 percent of U.S. emissions of the neurotoxin, remains up in the air.

The U.S. Environmental Protection Agency, the state health department and the energy industry say mercury pollution's effects are global and best reduced through a national cap-and-trade program.

Environmental and municipal groups including Boulder County contend that the pollutant's effects are worse near the power plants and that mercury needs tight regulation to avoid "hot spots" of health problems.

Those representing utilities also say mercury -capture technology remains in its infancy, something disputed by both environmental groups and officials from ADA-ES, a Littleton-based engineering firm selling mercury -control systems to utilities.

Colorado Air Quality Control Commission hearings that began Nov. 16 wrestled with quicksilver, minute doses of which can do long-term damage to developing brains. The governor-appointed board is responsible for state air-quality policy.

The commission was to decide on a controversial U.S. Environmental Protection Agency rule to limit mercury pollution in the coming years. Rather than electing to follow the EPA rule, a related state health department proposal or other proposals, the commission asked the state health department to assess possible impacts of a modified version of the state plan. The mercury decision is now slated for mid- to late January.

The EPA rule proposes a national mercury cap-and-trade program akin to one successfully instituted in the early 1990s for sulfur dioxide, a power-plant emission causing acid rain. EPA officials say their mercury rule, adopted in March 2005, would set a nationwide cap for mercury pollution as of 2010 and cut coal-fired power plant mercury emissions 70 percent by 2018.

In Colorado, the EPA-suggested cap would be 1,412 pounds per year through 2017 and 558 pounds in 2018 and beyond. Colorado power plants emitted an estimated 895 pounds in 2005.

The state's plan would impose 895 pounds as its limit for 2010-17 and provide incentives for plants that quickly install mercury controls. Paul Tourangeau, co-director of the state health department's Air Quality Control Division, which formulated the state plan, said it lets the state participate in the nationwide cap-and-trade program in a way that suits Colorado.

National issue comes home

The Environmental Protection Agency in 2000 classified mercury as a toxic, hazardous substance requiring coal-fired power plants to install mercury scrubbers. The Bush EPA mercury rule undid the Clinton-era rule.

Fourteen states sued the EPA in opposition. More recently, 22 states have introduced mercury controls more stringent than the EPA's guidelines, according to the National Association of Clean Air Agencies. States are requiring cuts of up to 90 percent in mercury pollution, speeding up federal requirements by several years and rejecting emissions trading, the association says.

Under a cap-and-trade plan, power plants emitting too much mercury could buy mercury -emission credits from those polluting less than their allotment or install mercury -control technologies.

The idea of trading a pollutant known to cause long-term damage to fetuses, babies and young children is reviled by environmental organizations and some government health officials.

"Our issue is, has been and will always be that trading of any kind is completely inappropriate for a powerful neurotoxin," said Pamela Milmoe, Boulder County's air and waste coordinator.

Local governments including Boulder, Gilpin, Garfield and Chaffee counties; the city and county of Denver; the cities of Aspen and Fort Collins and the San Juan Basin Health Department have joined in a coalition opposed to mercury -emissions trading. They and environmental organizations have proposed that the state require utilities to install mercury scrubbers to remove 90 percent of mercury from coal plants by the mid-2010s.

Milmoe says by joining a national trading scheme, even if Colorado controls emissions, utilities operating here could sell mercury credits to power plants elsewhere and "poison other communities."

"It's unconscionable," Milmoe said. "And it's clear that in other states there is possibly even greater potential for hot spots than even in Colorado."

The existence and prevalence of hot spots - places near power plants that bear the brunt of mercury pollution - are a key issue in the mercury debate. Western coal burned in Colorado produces mainly elemental mercury - as opposed to ionic or oxidized mercury prone to capture by raindrops falling near the plant, utility industry officials say.

If mercury is a global issue, then broad-based solutions such as a national mercury -trading regime make sense, trading proponents argue.

Disputed science and technology

James Sanderson, an attorney representing the Colorado Utilities Coalition in the mercury hearings, says even if Colorado had no power-plant emissions, mercury deposits in the state would fall 1 percent or less. A cap-and-trade program, he said, is a low-cost way to cut mercury emissions in a way that gives utilities "the most flexibility for plants to succeed."

"If you had a source that emitted oxidized mercury - the kind that falls to the ground close to source - you wouldn't want to do a trading program," Sanderson said. "Western coals are 85 percent elemental mercury , which goes up and becomes part of the global pool."

The 15 percent of power-plant mercury that is oxidized would be prone to precipitation by rainfall. Vickie Patton, a senior attorney for Environmental Defense in Boulder, pointed to the American Medical Association's Nov. 13 announcement that the EPA's mercury -trading approach "is potentially harmful for vulnerable populations."

"It is inescapable that mercury still has serious local impacts and broad impacts on human health," Patton said.

Frank Prager, managing director for environmental policy at Xcel Energy, said Xcel likes the flexibility of mercury trading as a means of reducing mercury emissions, which he said the company is committed to doing. Another challenge with mandating mercury controls, Prager said, is that mercury -capture technology remains in its infancy.

Xcel agreed to scrub mercury at its two existing Comanche power plants in Pueblo as part of a 2005 agreement with environmental and other groups paving the way for its 750-megawatt Comanche 3 plant, now under construction. Prager said Xcel is studying different approaches to mercury capture, among them using activated carbon particles to bind with exhaust gases.

"We don't want to make commitments we can't live up to, and we want to make sure what we do makes sense from the environmental and public health standpoints and the cost standpoint," Prager said.

George Offen, technical executive at the Electric Power Research Institute in Palo Alto, Calif., said Xcel's take on mercury controls is common in the industry.

"Our assessment is that many of the technologies have advanced and we are understanding them better," Offen said. "We do not feel that most are at a point where a user would consider them to be commercially ready."

But Jonathan Barr, vice president of sales and marketing at ADA-ES in Littleton, disagrees. His company has sold 12 mercury -scrubbing systems to power plants and has the contract for all three plants at Xcel's Comanche Station. His company's activated-carbon system is cutting mercury emissions more than 90 percent at the Presque Isle, Mich., plant, Barr said.