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Continental Carbon Company Clean Air Act Settlement

(Washington, DC – March 23, 2015) The U.S. Environmental Protection Agency (EPA) and the Department of Justice announced a Clean Air Act (CAA) settlement with Continental Carbon Company (Continental) that will significantly reduce air pollution from three carbon black manufacturing plants in Oklahoma, Alabama and Texas. This settlement will be the second settlement reached pursuant to the EPA’s New Source Review investigations of all carbon black manufacturing plants in the United States, part of the EPA’s national enforcement initiative aimed at reducing air pollution from the largest sources. 

Carbon black is a fine carbonaceous powder used as a structural support medium in tires and as a pigment in a variety of products such as plastic, rubber, inkjet toner, and cosmetics.  The oil used as the carbon black feed is low value high sulfur oil, and the manufacturing process creates large amounts of sulfur dioxide, and significant amounts of nitrogen oxide and particulate matter.

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Overview of Company

Continental owns and operates three carbon black manufacturing plants in Ponca City, Oklahoma, Phenix City, Alabama, and Sunray, Texas, and is headquartered in Houston, Texas. Continental is the fourth largest carbon black manufacturer in the United States.

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The EPA initiated investigation of the carbon black manufacturing sector and of Continental in 2007. Based upon Continental’s response to the EPA’s CAA Section 114 information requests and other information obtained during its investigation, the EPA concluded that modifications were performed at its plants that violated the Prevention of Significant Deterioration (PSD) provisions of the CAA. The parties initiated settlement discussions in 2008.

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Injunctive Relief

The consent decree secures injunctive relief from all of Continental’s carbon black manufacturing facilities in the United States. Compliance with the settlement will reduce sulfur dioxide (SO2), oxides of nitrogen (NOx), and particulate matter (PM) emissions by approximately 7,868 tons per year from 2010-2011 levels. The EPA estimates that the cost of the injunctive relief will be approximately $98 million.

The settlement requires:

  • Installation and operation of selective catalytic reduction  and compliance with enforceable 7-day and 365-day rolling average emissions limits for NOx at its two larger facilities in Ponca City, Oklahoma, and Phenix City, Alabama;
  • Installation and operation of dry or wet flue gas desulfurization and compliance with enforceable 7-day and 365-day rolling average emissions limits for SO2 and enforceable 3-hour average emissions limits for PM at its two larger facilities in Ponca City, Oklahoma, and Phenix City, Alabama;
  • Installation and operation of installation and operation of a low NOx combustion system (boiler, low NOx burner, and overfire air), and compliance with a facility-wide NOx permit limit in tons per year, at its Sunray, Texas, facility.
  • Compliance with enforceable permit limits of no more than 1.5 percent sulfur content feed, on an annual average basis, and 1.75 percent sulfur content feed, on a monthly average basis, by September 30, 2015, at its Sunray, Texas, facility;
  • Optimization and maintenance of existing control devices on other PM emissions points (e.g., baghouses, reactors, various vents and filters) at all three of its facilities;
  • Compliance with a fugitive emissions best management practices control plan at all three of its facilities;
  • Operation of an early warning PM detection system, that signals when there has been a non-nominal release of PM, at all three of its facilities; and
  • Installation and operation of NOx at all three of its facilities and SO2 CEMs at its two largest facilities in Ponca City, Oklahoma, and Phenix City, Alabama.
  • Cessation of operation of flares at all three of its facilities and operation of other technologies for compliance with the carbon black Maximum Achievable Control Technology standard, aside from specifically identified limited uses of the flare at its Sunray, Texas facility.

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Pollutant Reductions

As compared to Continental’s 2010-2011 emissions, EPA expects the following emission reductions to result from this settlement:

  • SO2 about 6278  tons per year
  • NOx about 1590 tons per year

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Health Effects and Environmental Benefits

The pollutants reduced under this settlement have numerous adverse environmental and health effects. Sulfur dioxides and nitrogen oxides can be converted to fine particulate matter once in the air. Fine particulates can be breathed in and lodged deep in the lungs, leading to a variety of health problems and even premature death. Other health and environmental impacts from the pollutants addressed in this settlement include the following:

Sulfur Dioxide – High concentrations of SO2 affect breathing and may aggravate existing respiratory and cardiovascular disease. Sensitive populations include asthmatics, individuals with bronchitis or emphysema, children, and the elderly. Sulfur dioxide is also a primary contributor to acid deposition, or acid rain.

Particulate Matter – Short term exposure to particulate matter can aggravate lung disease, cause asthma attacks and acute bronchitis, may increase susceptibility to respiratory infections and has been linked to heart attacks.

Nitrogen Oxides – Nitrogen oxides can cause ground-level ozone, acid rain, particulate matter, global warming, water quality deterioration, and visual impairment. Nitrogen oxides play a major role, along with volatile organic chemicals, in the atmospheric reactions that produce ozone. Children, people with lung diseases such as asthma, and people who work or exercise outside are susceptible to adverse effects such as damage to lung tissue and reduction in lung function.

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Environmental Mitigation Projects

The proposed consent decree requires Continental to spend $550,000 on environmental mitigation projects. No less than $200,000 will be spent at each of the Ponca City, Oklahoma, and Phenix City, Alabama facilities, on replacement of bag filters on the product storage tanks with continuous-duty, cartridge dust collector technology to minimize PM emissions. In addition, no less than $25,000 will be spent in each community surrounding each of its facilities, on various energy savings projects that also have criteria pollutant reduction benefits.

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Civil Penalty

Continental will pay a total of $650,000 in civil penalties.

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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:

Patrick Foley
Air Enforcement Division
U. S. Environmental Protection Agency
1200 Pennsylvania Ave, NW, MC 2242A
Washington, DC 20460 
(202) 564-7978

Kellie Ortega
Air Enforcement Division
​U. S. Environmental Protection Agency
1200 Pennsylvania Ave, NW, MC 2242A
Washington, DC 20460 
(202) 564-5529

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