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Cemex, Inc., Global Clean Air Act Settlement

(Washington, DC – July 27, 2016) The U.S. Environmental Protection Agency (EPA) and the U.S. Department of Justice (DOJ) today announced a settlement with Cemex, Inc., under which the company will invest approximately $10 million to cut emissions of harmful air pollution at five of its cement manufacturing plants in Alabama, Kentucky, Tennessee and Texas to resolve alleged violations of the Clean Air Act. Under the consent decree lodged in the U.S. District Court for the Eastern District of Tennessee, Cemex will also pay a $1.69 million civil penalty, conduct energy audits at the five plants, and spend $150,000 on energy efficiency projects to mitigate the effects of past excess emissions of nitrogen oxides (NOx) from its facilities. 

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Overview of Company

Cemex, Inc. (Cemex) is a Louisiana corporation, and maintains its corporate headquarters in Houston, Texas. Cemex is one of the largest producers of Portland cement in the United States, owning and operating 12 cement manufacturing plants. 

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The United States alleges in its Complaint that on more than one occasion, Cemex failed to obtain pre-construction permits and install and operate the appropriate nitrogen oxide (NOX) and sulfur dioxide (SO2) control technology for major modifications at one or more of its cement manufacturing plants that resulted in significant emissions increases.  The changes violated requirements contained in Section 165(a) of the Clean Air Act, regulations set forth in 40 C.F.R. § 52.21, and the corresponding state regulations in state implementation plans (SIPs). EPA’s regional offices in Atlanta (Region 4) and Dallas (Region 6) issued notices of violations (NOVs) for the modifications to the Knoxville, Tennessee and Odessa, Texas plants, respectively.

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Injunctive Relief

The settlement covers five Cemex plants and a total of seven kilns, located in several states: Knoxville, Tennessee; Demopolis, Alabama; Louisville, Kentucky; New Braunfels, Texas; and Odessa, Texas. The settlement requires Cemex to install and continuously operate modern pollution controls for nitrogen oxide (NOX) emissions at its kilns.  Specifically, the consent decree requires that Cemex install a selective non-catalytic reduction system (SNCR) for controlling NOX at seven kilns, and meet stringent emission rates at each kiln. For the control of sulfur dioxide (SO2) emissions, Cemex will rely on inherent scrubbing provided by kiln operation and a low-emissions baseline for SO2. Also, Cemex will be required to operate and maintain certified emission monitors for NOX and SO2 at all seven kilns under this settlement.   

The decree also requires Cemex to conduct detailed diagnostic energy audits at all facilities covered under the consent decree and spend $150,000 in mitigation dollars on energy efficient projects that reduce NOX emissions.  

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Pollutant Impacts

This settlement is part of EPA’s National Enforcement Initiative to control harmful emissions from large sources of pollution, which includes cement manufacturing plants, under the Clean Air Act’s Prevention of Significant Deterioration requirements. The total NOX emission reductions from the settlement are over 4,000 tons.  The settlement requires that Cemex maintain the already-low SO2 emissions at current rates or better. 

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Health Effects and Environmental Effects

NOX and SO2 have adverse effects on human health and the environment as discussed below:

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

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Civil Penalty

Cemex will pay a total penalty of $1,690,000 for violations resolved in the decree. Of the total civil penalty amount, $1,290,000 will be paid to the United States and $400,000 will be paid to the Knox County Air Pollution Control District, Knox County, Tennessee, a signatory under the decree.

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State and Regional Partners

The consent decree was negotiated with the assistance of the local agencies in Louisville, Kentucky and Knox County, Tennessee.

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Comment Period

The decree, lodged in U.S. District Court for the Eastern District of Tennessee, is subject to a 30-day public comment period and final court approval.  Information on how to comment on the consent decree is available on the Department of Justice website.

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For more information, contacts:

Robert G. Klepp
U.S. Environmental Protection Agency
1200 Pennsylvania Ave., N.W.
Washington, DC 20460
(202) 564-5805

Shaun Burke
Senior Environmental Engineer
1200 Pennsylvania Ave. NW
Washington, DC 20460
(202) 564-1039

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