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J.R. Simplot Company Clean Air Act (CAA) Settlement

(Washington, D.C. – December 3, 2015) The J.R. Simplot Company (Simplot) has agreed to upgrade and operate emissions controls, and implement improved emissions monitoring, at each of its five sulfuric acid plants across facilities in Lathrop, California (one plant), near Pocatello, Idaho (two plants), and in Rock Springs, Wyoming (two plants). Simplot will spend an estimated $42 million on these measures, and will pay a $899,000 civil penalty.

Overview of Company

Simplot is a privately held food and agribusiness company. Its main operations include ranching, food processing, mining, retail, and fertilizer production. Its fertilizer production operations include the operation of sulfuric acid production plants. The sulfuric acid plants use elemental sulfur to produce phosphoric acid. The phosphoric acid is then combined with ammonia to produce the common fertilizer diammonium phosphate. 

This settlement covers all five of Simplot’s sulfuric acid plants.

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The Complaint alleges that Simplot made modifications to its sulfuric acid plants, resulting in increased emissions of sulfur dioxide, without first obtaining pre-construction permits and installing required pollution control equipment, in violation of:  

  • The Clean Air Act (CAA) Prevention of Significant Deterioration (PSD) and Title V permitting requirement provisions, 42 U.S.C. §§ 7470-7492, 7661-7661f.
  • The State Implementation Plans (SIPs) of California, Idaho, and Wyoming, 42 U.S.C. § 7410.

The settlement also resolves alleged violations of PSD for emissions of sulfuric acid mist and PM2.5 at one of the sulfuric acid plants located near Pocatello, Idaho (known as the #400 Don sulfuric acid plant), as well as liability for any past violations at the sulfuric acid plants of the CAA New Source Performance Standards, 42 U.S.C. § 7411, and the corresponding regulations for sulfuric acid plants at 40 C.F.R. Subparts A and H.

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Injunctive Relief

At each of the five sulfuric acid plants, Simplot will upgrade and operate air pollution control processes to reduce emissions of SO2. Simplot will comply with both a short-term and a long-term emission rate at each sulfuric acid plant; collectively, the long-term emission rates are some of the lowest rates achieved in any sulfuric acid plant settlement to-date.

Simplot will implement improved continuous emissions monitoring systems to ensure compliance with the emission rates and will prepare and implement an operation and maintenance plan for each sulfuric acid plant. 

In addition, at the #400 Don sulfuric acid plant at the Pocatello facility, Simplot will comply with emission limits for sulfuric acid mist and PM2.5. The settlement also requires compliance with the New Source Performance Standards for sulfuric acid plants under 40 C.F.R. Part 60, Subparts A and H. 

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Mitigation Project

The Lathrop sulfuric acid plant is located in the San Joaquin Valley, which is currently designated as nonattainment for federal ambient air quality standards (known as NAAQS, or National Ambient Air Quality Standards) for PM2.5.

Simplot has agreed to a $200,000 mitigation project that will provide incentives to residents of the San Joaquin Valley to replace older, higher-emitting wood-burning devices with cleaner, lower-emitting hearth options. These wood stove change-outs will reduce emissions of PM2.5, along with emissions of volatile organic compounds, carbon monoxide, and hazardous air pollutants.  

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Pollutant Reductions

Once all of the upgraded emissions controls have been implemented, this settlement will result in an estimated 2,540 tons per year reduction of SO2 emissions. In addition, the mitigation project should provide approximately 70 tons per year of additional emission reductions (combined reductions of carbon monoxide, volatile organic compounds, PM2.5, and hazardous air pollutants). 

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Health Effects and Environmental Benefits

Exposure to SO2 can affect breathing, including bronchoconstriction and increased asthma symptoms. SO2 emissions can also react in the atmosphere to form small particles of sulfates. These fine particles (also known as PM2.5) can penetrate deeply into sensitive parts of the lungs and can cause or worsen respiratory disease, such as emphysema and bronchitis, and can aggravate existing heart disease, leading to increased hospital admissions and premature death.

Fine particles (PM2.5) are also the main cause of reduced visibility (haze) in parts of the United States. SO2 is also a primary contributor to acid deposition, or acid rain. 

Since SO2 is a precursor to the formation of PM2.5, the SO2 emissions controls at the Lathrop facility sulfuric acid plant will also offer some benefits in helping the San Joaquin Valley to address the PM2.5 NAAQS nonattainment status.

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Civil Penalty

Simplot will pay an $899,000 civil penalty:

  • the United States will receive $732,000;
  • the State of Idaho will receive $167,000.

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State and Regional Partners

The State of Idaho, on behalf of its Idaho Department of Environmental Quality, and the San Joaquin Valley Air Pollution Control District 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 District of Idaho, is subject to a 30-day public comment period and final court approval. Information on submitting comment is available at the Department of Justice website.

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For more information, contact:

Daniel Schaufelberger 
U. S. Environmental Protection Agency
77 West Jackson Blvd. (AE-17J)
Chicago, IL  60604-3590 
Phone:  (312) 886-6814

Virginia Sorrell
Water Enforcement Division
U. S. Environmental Protection Agency
1595 Wynkoop St. (8MSU)
Denver, CO  80202
Phone:  (303) 312-6669

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