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Chemical Release Reporting

The Toxics Release Inventory (TRI) program is part of the Emergency Planning and Community Right-to-Know Act of 1986 (EPCRA). EPCRA requires companies with 10 or more employees, in certain industries, to collect and publicly disclose information about how they manufacture, process or use any of nearly 650 chemicals on a special list developed by the U.S. EPA. Out of the 650 chemicals on the TRI list, AEP reported 25 in 2017.

Companies are required to report the amount of these chemicals they manufacture or process when that amount exceeds 25,000 pounds a year. For most chemicals that are simply used, such as chemicals purchased to clean a facility, the amount required to trigger a report is 10,000 pounds or more in a year. A few chemicals have much lower reporting thresholds. The U.S. EPA establishes these numbers. The report is not related in any way to health or environmental standards.

In general, coal-fired power plants need to report on very few of the 650 chemicals on the U.S. EPA's list. However, because of the nature of our industry and the amount of coal we consume, large coal-fired electric power plants will be listed at or near the top of rankings, when compared with other reporting industries, in terms of number of pounds reported by a single facility. Although the chemicals reported by AEP are released in large amounts, they generally rank low in toxicity.

What Does This Mean?

AEP wants you to know what the TRI numbers mean to you and your family. There are too many variables involved to easily determine the specific risk that each of the chemicals at power plants might pose to any individual. However, the U.S. EPA and the Electric Power Research Institute have studied releases by utilities and determined that most pose extremely low risk to public health and the environment.

Where AEP Chemical Releases Go

AEP has aggressively invested in air emission control equipment over the past decade-plus. Prior to these investments, about 80 percent of AEP's chemical releases reported on the TRI were emitted to the air from power plant stacks. With the addition of emission control equipment, releases to air are currently less than 20 percent of total releases.

The bulk of our air releases take the form of sulfuric acid aerosol (H2SO4). Trace amounts of sulfur are naturally present in coal. When the coal is burned, the sulfur is released in small amounts, some of which combines with oxygen in the air to form sulfur dioxide (SO2). As the sulfur dioxide travels through the exhaust gas in the power plant's stack, it reacts with moisture in the air to form a sulfuric acid aerosol, which becomes more diluted as it exits tall stacks and disperses into the atmosphere. However, emission control equipment has resulted in AEP's releases of the sulfur dioxide precursor declining by 95% since 1990.

Approximately two-thirds of AEP's TRI releases are in the form of coal combustion products (CCPs). The majority of the CCPs are transferred to landfills regulated by environmental agencies and maintained by AEP. Some of the CCPs are recycled into other products. For example, CCPs can be used in concrete blocks, road-fill material, plastics and paint. Elements in CCPs include antimony, arsenic, barium, beryllium, chromium, cobalt, copper, lead, manganese, mercury, nickel, selenium, thallium, vanadium and zinc.

Releases to water, which are carefully monitored in compliance with water quality regulations, represent less than one percent of the releases we report. These include the chemicals in CCPs (listed above), chlorine, and ammonia.

AEP's TRI Release and Their Potential Impacts

The chemicals we report to the U.S. EPA depend on the amount and type of coal burned and specific emission controls used at each plant. Although the chemicals reported by AEP are released in large amounts, they generally rank low in toxicity.

General information about these chemicals is available through a number of sources, including public libraries, the internet, and poison control centers.

Various U.S. EPA offices have developed different chemical ranking systems to provide a sense of how chemicals compare to each other in terms of their potential impact on the environment or public health.

Chemical rankings provide some helpful information, but actual risk is based on a combination of factors. These include:

  • The chemical's inherent toxicity
  • How it is dispersed or reacts in the environment
  • The mechanism of exposure (whether through breathing, ingestion or skin contact)
  • The amount to which an individual is exposed

We have developed tables that show the amount of TRI-listed chemicals released by each AEP power plant, as well as a total for the entire AEP System. To obtain a copy, contact:

We have developed tables that show the amount of TRI-listed chemicals released by each AEP power plant, as well as a total for the entire AEP System. To obtain a copy, email David Miller.

What AEP is Doing About Releases

Chemical releases are an unavoidable consequence of turning fossil fuels into useful electrical energy. Through the years, we have made significant investments to reduce or repurpose various chemical emissions and waste streams. The AEP system uses many technologies that control or eliminate certain types of water, air and solid waste releases from its coal-fired, natural gas-fired, oil-fired power plants, coal mining facilities, nuclear plants and other operations.

To keep emissions low while we produce the affordable, reliable supply of electricity our customers demand, we will continue to support research to find more efficient, cleaner ways to burn coal and use other fuel sources that make economic sense. AEP is also finding ways to lower its use of electricity and encouraging customers to use electricity wisely, which result in less usage of fossil fuels and thus less waste.

What's Changed

Factors affecting TRI release estimate change from year to year for American Electric Power facilities. These factors include: fuel use and characteristics, data source changes, facility operational changes and updated estimation methodologies.

  1. Fuel Use and Characteristics: Fuel for a facility is purchased from different sources depending on market conditions. The chemical characteristics of different coal mixes can vary depending on the amount of fuel from each source, which contributes to fluctuations in TRI estimates from year to year.
  2. Data Source Changes: New or additional sampling data was collected to meet existing regulation requirements. This new data, coupled with inherent analytical variability is used in release estimates.
  3. Facility Operational Changes: Changes in customer demand and economic conditions cause fluctuations in generation. These operational changes impact fuel usage, which in turn impacts TRI release estimates. Coal combustion products, which correlate directly to fuel usage, also may change, which contributes to a change in total releases to land.
  4. Estimation Methodologies: TRI data is developed using Electric Power Research Institute (EPRI), U.S. EPA, and other research and government organization estimation methods. Continuing research revises and updates these methods to provide more accurate estimates which affects data from year to year.
  5. New Technologies: Installation of equipment for process improvements or emission and/or discharge control may impact releases. Process or equipment modifications may change the release totals, shift the release amounts from one media to another, or require use of chemicals not previously reported.

Additional TRI Information

Past Data

Tables for Individual Plants

Chemical Profiles

External TRI Information

Visit the EPA Web site for more TRI-related information.