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Terra Industries Clean Air Act Settlement

(Washington, DC - April 19, 2011) The U.S. Environmental Protection Agency (EPA) and the U.S. Department of Justice today announced Terra Industries Inc., one of the nation's largest producers of nitric acid and nitrogen fertilizers, has agreed to pay $625,000 in civil penalties to settle alleged violations of the federal Clean Air Act at nine of its plants in Iowa, Mississippi, and Oklahoma. As part of the settlement, Terra will also spend an estimated $17 million to install and implement new controls and technologies that are expected to reduce harmful nitrogen oxide emissions at its facilities by at least 1,200 tons per year.

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Overview of Company

Terra Industries is the largest producer of nitric acid in the United States. This nitric acid is primarily used in the production of nitrogen fertilizer. Terra Industries is a wholly owned subsidiary of CF Industries. This settlement covers Terra's nine nitric acid plants operating at four facilities:

  • Sergeant Bluff, Iowa (2)
  • Verdigris, Okla. (2)
  • Woodward, Okla. (1)
  • Yazoo City, Miss. (4)

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The complaint alleges that Terra Industries conducted modifications that triggered New Source Review (NSR), Prevention of Significant Deterioration (PSD), and/or New Source Performance Standard (NSPS) obligations under the federal rules for the pollutant nitrogen oxides (NOx). Each nitric acid plant should have complied with the NSR and/or PSD requirements, by applying for and receiving a NSR and/or PSD Permit under its applicable State Implementation Plan (SIP), and had these requirements incorporated into its Title V permit. The complaint alleges that some of Terra's plants also should have complied with the NSPS for Nitric Acid Production Plants at 40 C.F.R. Part 60 Subpart G.

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Injunctive Relief

The settlement requires Terra Industries to install new catalytic reduction units or upgrade existing equipment. Continuous emission monitors will be required for NOx at all facilities. The value of the injunctive relief is estimated to be more than $17 million.

Once fully implemented, these measures are expected to reduce emissions of nitrogen oxides (NOx) by 1,205 tons per year.

Each plant will meet a long term emission limit (i.e. 365-day production weighted rate) of 0.60 lb of NOx per ton of 100 percent nitric acid and a short term emission limit (i.e. 3-hour average) of 1.0 lb of NOx per 100 percent nitric acid.

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Pollutant Reductions

Once injunctive relief measures are fully implemented NOx emissions are expected to drop by 1,205 tons per year (tpy). Below is a breakdown of these reductions by facility:

  • Sergeant Bluff, Iowa - 54 tpy
  • Verdigris, Okla. - 296 tpy
  • Woodward, Okla. - 56 tpy
  • Yazoo City, Miss. - 799 tpy

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Health and Environmental Effects

  • Nitrogen Oxides - NOx can cause or contribute to a variety of health problems and adverse environmental impacts, such as ground-level ozone, acid rain, global warming, water quality deterioration, and visual impairment. Affected populations include children and people with lung diseases such as asthma. Exposure to these conditions can cause damage to lung tissue for people who work or exercise outside.

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Civil Penalty

Terra Industries will pay a civil penalty of $625,000. Of this, the US will receive $325,000 and states of Oklahoma, Mississippi, and Iowa will each receive $100,000.

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State Partners

Oklahoma, Mississippi, and Iowa partnered with U.S. Environmental Protection Agency and U.S. Department of Justice in achieving this settlement.

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Comment Period

The proposed settlement, lodged in the U.S. District Court for the Northern District of Iowa, is subject to a 30-day public comment period and final court approval. Information on submitting comments is available at the Department of Justice website.

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For more information, contact:

Robert Parrish
U. S. Environmental Protection Agency
1200 Pennsylvania Ave, NW (MC 2242A)
Washington, DC 20460
(202) 564-6946
Robert Parrish (

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