State pressed to monitor SO2 pollution near coal plants

Jun 28 - McClatchy-Tribune Regional News - Jeffrey Tomich St. Louis Post-Dispatch

An environmental group released a report Thursday showing that most of the St. Louis area may violate new standards for sulfur dioxide and is exposed to unhealthy levels of the pollutant from the stacks of two area coal-burning power plants.

The report is a product of computer modeling commissioned by the Sierra Club, and is central to the environmental group's push to convince state regulators to install monitors near two of the state's largest sources of sulfur dioxide (SO2), Ameren Missouri's Labadie and Meramec plants.

Ameren disagreed with the report's conclusions and said steps taken in recent years to reduce sulfur dioxide emissions put it in compliance with current and new federal pollution standards.

The debate comes as Ameren defends itself in a federal lawsuit by the Environmental Protection Agency, which is charging the utility with federal Clean Air Act violations related to excessive sulfur dioxide emissions from the Rush Island plant in Jefferson County.

The Sierra Club formally submitted its monitoring request on Thursday to the Missouri Department of Natural Resources, the state agency charged with implementing more stringent federal pollution standards issued by the EPA two years ago.

Sulfur dioxide is a potent gas that can trigger asthma attacks and other respiratory problems. Fossil fuel-burning power plants are responsible for 73 percent of sulfur dioxide emissions nationwide.

The EPA's revised standard, issued in 2010, established limits based on maximum concentrations over a one-hour period to protect the public from short-term exposure. It is the first revision of maximum sulfur dioxide concentrations since standards were issued in 1971.

The new one-hour standard makes it critical to assemble data on sulfur dioxide concentrations in the air near major sources, such as coal-fueled power plants, the Sierra Club said in its comments to DNR.

Currently, there are no sulfur dioxide monitors in Franklin County, the location of state's largest source of the pollutant, Ameren Missouri's Labadie power plant. Nor are there any sulfur dioxide monitors in St. Louis County, the most populous county in Missouri and site of Ameren's Meramec plant.

Without monitors, there's no data for the state to evaluate the health impact on area residents, John Hickey, the Sierra Club's Missouri chapter chair, told members of the Missouri Air Conservation Commission. The commission held its monthly meeting Thursday in St. Louis County.

"Ignorance is not bliss," Hickey said. "We've got a public health crisis. The science is clear. (Sulfur dioxide) limits are not being met and we can't just put our heads in the sand and say it's not happening."

Kyra Moore, director of DNR's air pollution control program, said the state will stick with the network of air monitors that was previously submitted to the EPA for approval last summer.

Ameren, meanwhile, points to the $600 million it spent on "scrubbers" to remove sulfur dioxide and other pollutants from emissions at the Sioux power plant in St. Charles County. It also has begun burning lower-sulfur coal at Missouri plants and has installed other equipment to remove more particulate matter and mercury, said Michael Menne, Ameren Missouri's vice president of environmental services.

"Any decision to install ambient air monitoring stations around our energy centers would of course be up to the state of Missouri but we would not be opposed to such actions," Menne said.

The nature of sulfur dioxide pollution and the change in regulations make the issues of how and where to measure for concentrations in the air both complex and controversial.

"It's a very difficult decision where to put monitors based on the funding and EPA rules," Moore said.