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El Dorado Chemical Co. et al. Clean Air Act Settlement

(March 19, 2014 - Washington, DC) - LSB Industries, Inc. (LSB), the largest merchant manufacturer of concentrated nitric acid in North America, and four of its subsidiaries have agreed to reduce harmful emissions of nitrogen oxides (NOx) by meeting emission limits that are among the lowest for the industry in the nation at plants in Alabama, Arkansas, Oklahoma and Texas, the U.S. Environmental Protection Agency (EPA) and Department of Justice announced today.

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Overview of Companies and Location of Facilities

LSB Industries and its four subsidiary companies (El Dorado Chemical Company, Cherokee Nitrogen Company, Pryor Chemical Company, and El Dorado Nitrogen Company) are parties to the Consent Decree.

LSB is the largest merchant marketer of concentrated nitric acid in North America.  LSB produces nitrogen-based fertilizers that are used to grow crops, as well as concentrated nitric acid used to produce various specialty chemicals for metal treatment, diesel fuel additives, herbicides, ordnance, pharmaceuticals, semiconductors, herbicides, pesticides and metal treatment. 

The settlement covers 10 nitric acid plants in the following locations:

  • Cherokee, Alabama (2 operating plants)
  • El Dorado, Arkansas (3 operating plants, 1 plant shutdown)
  • Pryor, Oklahoma (3 operating plants)
  • Baytown, Texas (1 operating plant)

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The Complaint alleges that three of LSB’s subsidiaries (Cherokee Nitrogen Company, El Dorado Chemical Company, and Pryor Chemical Company) constructed or made modifications to its nitric acid plants, resulting in increased emissions of nitrogen oxide (NOx), without first obtaining pre-construction permits and installing required pollution control equipment, in violation of:

  • The Clean Air Act (CAA) Nonattainment New Source Review, Prevention of Significant Deterioration, and Title V permitting requirement provisions, 42 U.S.C. §§ 7470-7492, 7501-7511f, 7661-7661f.
  • The State Implementation Plans (SIPs) in Alabama, Arkansas, and Oklahoma, 42 U.S.C §7410.
  • Subparts A and G of the New Source Performance Standards, 40 C.F.R. §§ 60.2, 60.70, 60.72, 60.73, and 60.82, including the NOx emissions limit and the requirement to install, calibrate, maintain and operate a continuous emission monitoring system for the measurement of NOx.

The settlement also resolves alleged violations based on Oklahoma law at the Pryor, Oklahoma facility, in violation of:

  • Oklahoma Admin. Code (OAC) 252:100-9-7(a) and (b), for failure to submit immediate notice and 30-day reports of excess emission events.
  • OAC 252:100-8-1.3, and 27A O.S. § 2-5-112(A) for failure to comply with permit conditions of ODEQ Air Quality Permit No. 2008-100-C (M-2) (PSD) at the ammonia plants and ammonium nitrate plants.

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Injunctive Relief

The companies will spend an estimated $6.3 to $11.7 million on controls to reduce emissions of NOx and to install continuous emissions monitors. The companies will also undertake an environmental mitigation project valued at $150,000 to remediate acidified soils and reforest land in Union County, Arkansas.

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NOx Controls

  • Installation and operation of air pollution control equipment using selective catalytic reduction (SCR) and/or non-selective catalytic reduction (NSCR) technology to control emissions of NOx;
  • Obligation to comply with NOx emissions rates of 1.0 lb/ton (short-term) and 0.6 lb/ton (long-term).
  • Installation and operation of continuous emission monitoring systems.

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Pollutant Reductions

Once all emissions controls and emissions-reduction practices have been implemented, this settlement will result in an estimated reduction in NOx emissions of more than 800 tons per year.

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Health Effects and Environment Benefits

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

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Environmental Mitigation Project

The settlement also requires the companies to perform a mitigation project valued at $150,000 in Union County, Arkansas adjacent to the Ouachita River (approximately 10 miles northeast of El Dorado, Arkansas).  The companies will work with Union County to remediate 10 acres of land with acidified soils. NOx emissions, such as those from the nitric acid plants in El Dorado, Arkansas, contribute to soil acidification. After restoring the soils, LSB will execute a reforestation plan intended to provide species diversity consistent with a mixed hardwood/pine forest typical of the Ouachita River Basin with diverse native trees. Implementation of this projected is expected to have the environmental benefits of reduced sediment transport, reduced stormwater runoff, including nutrients and low pH stormwater, improved wildlife habitat, and sequestration of carbon dioxide.

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Civil Penalty

The companies will pay a $725,000 civil penalty. $362,500 of the penalty will be paid to the United States, $206,250 will be paid to the Oklahoma Department of Environmental Quality and $156,250 will be paid to the Alabama Department of Environmental Management.

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State and Regional Partners

The Oklahoma Department of Environmental Quality and Alabama Department of Environmental Management joined the United States in this consent decree.

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Comment Period

The proposed settlement, lodged in the U.S. District Court for the Western District of Oklahoma, 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

Melanie Shepherdson
Air Enforcement Division
U.S. Environmental Protection Agency
1200 Pennsylvania Ave., NW MC 2242A
Washington, DC 20460
(202) 564-8386
Melanie Shepherdson (

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