DNR finds area around Ameren’s Labadie power plant “unclassifiable”
From Missouri Public Radio
The Missouri Department of Natural Resources is recommending that the area around Ameren’s Labadie power plant be designated as “unclassifiable” for sulfur dioxide pollution.
That means state regulators could not determine whether or not air quality in those parts of Franklin and St. Charles counties meets the federal health standard.
This is a victory for AIM and Ameren. Throughout the last session, AIM fought for legislation that required DNR to make its decisions on air quality based on actual, up-to-date, monitoring. It appears in this case that DNR has done this and come up with conclusions it did not expect.
The state had three alternatives for designating the levels of sulfur dioxide around the Labadie plant: attainment, nonattainment and unclassifiable. Here is how those designations are defined by the U.S. Environmental Protection Agency under the Clean Air Act’s National Ambient Air Quality Standards (NAAQS):
Nonattainment: An area that the EPA has determined violates the 2010 SO2 NAAQS, based on the most recent three years of ambient air quality monitoring data or an appropriate modeling analysis, or that EPA has determined contributes to a violation in a nearby area.
Attainment: An area that the EPA has determined meets the 2010 SO2 NAAQS and does not contribute to a violation of the NAAQS in a nearby area based on either: a) the most recent three years of ambient air quality monitoring data from a monitoring network in an area that is sufficient to be compared to the NAAQS per EPA interpretations in the Monitoring Technical Assistance Document (TAD), or b) an appropriate modeling analysis.
Unclassifiable: An area where the EPA cannot determine based on available information whether the area is or is not meeting the 2010 SO2 NAAQS and whether the area contributes to a violation in a nearby area.
Translation: to decide whether levels of sulfur dioxide are unhealthy or not, you either need three years of air monitoring data or you have to rely on computer modeling. In August, the Missouri Department of Natural Resources proposed two options for public comment: nonattainment based on modeling and unclassifiable based on monitoring.
The state’s modeling estimates were based on the most recent three years of actual sulfur dioxide emissions data provided by Ameren for the Labadie plant. They purported to show violations of the federal standard, or nonattainment. But these were just computer projections that were, apparently, not trustworthy.
Conversely, data from two air monitors that Ameren installed near the plant in April did not show any air quality problems. In addition, the state pointed to some of its own monitoring from the 1990s that measured sulfur dioxide levels under the current EPA limit. But federal law requires three years of recent air monitoring to conclude an area is in “attainment,” so the state proposed Labadie be designated as “unclassifiable.”
After reviewing public comments, including a letter from Associated Industries of Missouri, the MDNR released its final recommendation for the area around Labadie on Tuesday: unclassifiable.