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Air Quality in Indiana

Air Quality in Indiana > Air Quality 101 > February 2014: The Toxics Release Inventory (TRI) and Air Quality February 2014: The Toxics Release Inventory (TRI) and Air Quality

February 2014: The Toxics Release Inventory (TRI) and Air Quality

Once a year, U.S. EPA releases an analysis on figures reported by industry under the federal Toxics Release Inventory (TRI) program. The figures are estimated totals of the toxic chemicals that were released to the air (in compliance with air permits), discharged to the water (in compliance with wastewater permits), disposed of in permitted landfills, otherwise managed through recycling, energy recovery and treatment, or released in an uncontrolled manner (for example, in an emergency or accident).

U.S. EPA’s TRI analysis is used by federal and state regulators, including IDEM, in conjunction with many other environmental assessment programs, to determine whether certain industrial activities may be adversely impacting the quality of our air, land or water. The TRI analysis helps us watch for trends and in some cases trigger sector-wide initiatives to reduce the use of certain chemicals, improve processes, or switch to less-toxic chemicals. Local emergency response agencies use TRI to stay informed about chemicals being used by facilities, so that they will be better prepared to protect the public health in an emergency. Citizens have a right to know about toxic chemicals being used by businesses and industries in their neighborhoods, and the public can find this type of information in the TRI.

However, by itself, TRI is not useful for determining the quality of our air, land or water. The following examination of the Indianapolis Star’s February 9, 2014 article, “IPL plant still No. 1 polluter in Indy, EPA says,” helps illustrate the point.

The figures in the article appear to be correct, but are misleading because the data is provided out of context and the article lacks complete information about the sources of toxic air pollutants in Marion County. The IPL plant is cited in the article as the largest industrial toxic polluter in Marion County. That may be correct, but additional information is needed in order to reach a conclusion about the plant’s impact on air quality.

Here are additional facts: Industrial sources, including the IPL plant, account for less than 13 percent of the air toxics being emitted in Marion County (it is correct that the IPL plant is the largest single emitter among those sources). A review conducted of total air toxics emitted in Marion County for 2008 shows 49 percent comes from homes and small industries that are not required to report their releases to TRI. About 9 percent comes from non-road sources, such as construction equipment. Another 30 percent comes from automotive sources such as cars, trucks and buses.

According to the TRI database, in 2012 the IPL Harding Street plant released 1,122,273 pounds of air toxics (561.1 tons). In 1998 (the first year that data is available), the plant reported 2,220,457 pounds of air toxics emission (1110.2 tons). At first glance this would suggest that a reduction of air toxics of about 49 percent has occurred during this period. However, the specific air toxics included varies from year to year (per U.S. EPA guidance). Looking at only those compounds reported in both years (1998 and 2012), the plant has shown a similar reduction of approximately 50 percent. Nearly all of the air toxics are from three specific compounds—sulfuric acid, hydrochloric acid, and hydrogen fluoride—that have been included in both years.

The article indicates that IPL has spent more than $280 million in emission controls. (The article states that an additional $500 million in upgrades are planned at the Harding Street facility and the facility in Petersburg.) Looking at TRI figures makes one wonder why the emission controls to date have not achieved greater reductions. It may be helpful to understand that when IPL and other utility owners estimate air toxic emission rates, they make assumptions.

A scrubber that removes sulfur dioxide will also remove sulfuric acid, and it probably will control hydrochloric acid and hydrogen fluoride. The question is how much? These are the three air toxics that make up nearly all (99.7 percent) of the total air toxics reported by this plant. It would be very expensive to test and determine the amount of control they were actually getting for each air toxic they are required to report. But there is no penalty for over reporting values in TRI, so estimates are often based on the assumption that air pollution controls are NOT controlling air toxics.

The final fact about the chemicals reported under TRI is that they are not all equally toxic. Many of the compounds contained in the TRI database are not considered hazardous air pollutants by U.S. EPA. Ammonia, copper compounds, and zinc compounds are three examples of chemicals that must be reported under TRI but are not on U.S. EPA’s list of hazardous air pollutants. The point is that just looking at a total amount of air toxics reported under the TRI program tells you very little. You need to know the toxicity of the individual compounds to be able to compare risks from the emissions.

The bottom line is not whether IPL’s Harding Street facility is a large industrial emitter of air toxics. It probably is, but a conclusion cannot be drawn from TRI reports alone – it would require factoring in the correct control levels. And to reach a conclusion on whether this is important or not, one must look at the total air toxics in the county to put it into perspective. IDEM looks at all available information to determine the best alternatives for achieving healthy air quality for all Hoosiers.

Questions can be directed to kbaugues@idem.IN.gov.

Keith Baugues