Mercury pollution in Colorado rose by 69.5 percent in one year, according to newly released data, catching state health officials off-guard and raising the eyebrows of an analyst for one environmental group.
"It may well be that there's much more mercury out there than we were previously aware," says Kirk Mills, who coordinates the state's inventory of toxic pollutants.
But Isaac Silverman, a clean-energy associate with Environment Colorado, wonders if pollution really is rising. He suggests that companies might have padded the data to position themselves for a new opportunity to profit.
"For years, [utilities] have underreported levels of mercury pollution from their power plants," he says. "Now, when their mercury pollution can earn them money, reported emissions skyrocket. It smells like a scam to me."
Either way, Silverman says, Colorado appears headed for pollution trouble.
Statewide, mercury emissions rose from 794 pounds in 2003 to 1,346 pounds one year later, according to annual Toxic Release Inventory data released last week by the state's Department of Public Health and Environment.
Health experts say overexposure to mercury pollution, which may be inhaled or ingested, can damage fetuses, kidneys and the brain.
Xcel Energy, the state's largest energy company, largely drove the upward spike. Its five coal-power plants, which include the Comanche plant in Pueblo, reported an aggregate 541 pounds of emissions in 2004 as compared to just 51 the year before.
Xcel spokesman Mark Stutz says the energy company did not burn more coal in 2004, but rather changed its methods for estimating mercury pollution. Xcel switched to a method established by the Electric Power Research Institute, a nonprofit coalition of utilities, Stutz says.
"We moved to that method because it gave us what we thought is a better measurement," he says.
In the past, Xcel used a formula created by the Environmental Protection Agency to estimate mercury emissions at the plants, Stutz says.
Silverman worries that Xcel and other companies have incentives to switch their methodology to one that inflates mercury emissions. Later this year, the state is expected to issue a rule that establishes new maximum limits for mercury pollution. The higher the reported emissions are currently, the more room a company might have to demonstrate declining pollution in coming years, Silverman says.
He adds that higher mercury emissions might help a company make a case to collect or sell pollution credits through a system the state is seeking to create under the EPA's 2005 Clean Air Mercury Rule.
The proposed system would allow Colorado to pollute more while granting the state's power companies the right to trade valuable mercury pollution credits with each other. The idea has been criticized as too lenient by health officials, medical associations and environmentalists.
Pueblo gets schooled
Silverman says the increase in mercury statewide suggests that utilities have been "gaming the system" to their advantage by inflating the numbers.
If, however, the estimates are accurate, mercury pollution at Pueblo's Comanche rose from 16 pounds in 2003 to 133 pounds in 2004.
Given that estimate, and data from the city's Rocky Mountain Steel mill the state's worst mercury polluter Pueblo shouldered 38 percent of the state's reported mercury emissions in 2004.
Howard Roitman, the state health department's director of environmental programs, says state officials are not monitoring hospitals and clinics for signs of trouble, such as infants born with abnormalities.
Health officials are, however, closely watching the state's bodies of water in hopes of detecting potential mercury problems early on.
As a result of that monitoring, the state has posted warnings to anglers at five reservoirs, four of them in the southwestern part of the state. The fifth is Teller Reservoir, on the southern side of Fort Carson, where it now is illegal to fish for northern pike and largemouth bass because of mercury contamination.
City-owned Colorado Springs Utilities reported drops in mercury emissions at its two coal plants, Ray D. Nixon and Martin Drake.
At Nixon, mercury emissions fell from 31 pounds in 2003 to 12.8 pounds one year later. At Martin Drake, mercury emissions dropped by nearly 13 pounds.
Michael Brady, environmental manager for Martin Drake, attributes the change to a lower concentration of mercury in the coal the plant is burning. He describes the reduction as a coincidental, supply-driven boon to the plant.
"The coal just varies sometimes," he says, adding that reported emissions at the plant came from the utility's own estimate.