Taconite Iron Ore Processing: National Emission Standards for Hazardous Air Pollutants (NESHAP)

Rule Summary

On January 31, 2024, the Environmental Protection Agency finalized amendments to the National Emission Standards for Hazardous Air Pollutants (NESHAP) for Taconite Iron Ore Processing Plants, strengthening existing emissions limits for harmful acid gases such as hydrogen chloride and hydrogen fluoride, and establishing new emission limits for mercury.

This action reflects a court decision in Louisiana Environmental Action Network v. EPA, which found that EPA has the obligation to address unregulated hazardous air pollutant emissions from a major source category when the Agency conducts the 8-year technology review required by the Clean Air Act. This action addresses gaps in the regulation of hazardous air pollutants (HAP) that remained following the final Residual Risk and Technology Review for this source category on July 28, 2020.

HAP, or air toxics, are those pollutants known to cause cancer or other serious health effects. The initial rule was designed to reduce emissions of HAP, including metal compounds (e.g., manganese, arsenic, and lead), acid gases (i.e., hydrogen chloride and hydrogen fluoride), and products of incomplete combustion (e.g., formaldehyde). Exposure to these substances has been demonstrated to cause adverse health effects, including chronic and acute disorders of the blood, heart, kidneys, reproductive system, respiratory system and central nervous system. Some of these substances are considered carcinogens.

The final NESHAP amendments would establish the first Clean Air Act limits on mercury from taconite iron ore facilities and are expected to reduce mercury emissions by about 33 percent -- or 247 pounds per year. These reductions are expected to reduce the amount of mercury that deposits to water and land in the Great Lakes region, improving health protection for local communities, including Tribal Nations and low-income populations. Mercury that deposits into waterbodies or land transforms to methylmercury, a powerful neurotoxin that bioaccumulates in fish and can harm humans who consume significant amounts of these fish, especially for unborn babies’ growing brains and nervous systems.

The final rule also will reduce hydrochloric acid emissions by about 72 percent, hydrofluoric acid emissions by about 29 percent, and particulate matter emissions by about 35 percent relative to baseline. Exposure to hydrochloric acid and hydrofluoric acid emissions can cause irritation and inflammation of the respiratory tract in people, while scientific evidence shows that long- and short-term exposures to particulate matter can harm people’s health, leading to heart attacks, asthma attacks, and premature death.

A taconite iron ore processing facility separates and concentrates iron ore from taconite, a low-grade iron ore, and produces taconite pellets, which are approximately 60 percent iron and about ½ inch in diameter. These pellets are then utilized, mainly, in blast furnaces making iron and steel and in the cement industry.