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CEMEX Lyons Plant Settlement

(Washington, DC - April 19, 2013) The U.S. Department of Justice (DOJ) and the U.S. Environmental Protection Agency (EPA) announced today that CEMEX, Inc., the owner and operator of a Portland cement manufacturing facility in Lyons, Colo., has agreed to operate advanced pollution controls on its kiln and pay a $1 million civil penalty to resolve alleged violations of the Clean Air Act (CAA).

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Overview of Company

CEMEX is a global building materials company headquartered in Mexico. CEMEX provides cement, ready-mix concrete, aggregates, and building materials for construction projects in the industrial, commercial, residential and municipal sectors, with 14 cement manufacturing plants, more than 100 aggregate quarries and hundreds of ready-mix concrete plants in the United States.

CEMEX is the largest producer of cement and ready-mix concrete in the U.S., capable of producing more than 15 million tons of cement per year. CEMEX’s U.S. headquarters is in Houston, Texas.

The CEMEX Lyons facility is located in Lyons, Colorado. The facility operates a precalciner kiln with a capacity of 550,000 tons per year. The facility is located 20 miles from Rocky Mountain National Park. Prior to the production turndown in 2008, CEMEX emitted over 1,700 tons (per year) of NOx from the Lyons facility.

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The Complaint alleges that CEMEX made major modifications to the Lyons facility resulting in increased emissions of NOx without first obtaining a pre-construction permit and installing required pollution control equipment. These actions violate the Clean Air Act (CAA) Prevention of Significant Deterioration (PSD) provisions, Part C of Title I of the CAA. As required under the CAA, the EPA issued a Notice of Violation to CEMEX and on January 9, 2009, the Department of Justice filed a civil complaint in District Court for the District of Colorado. This settlement resolves all of the alleged violations in the Complaint.

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Injunctive Relief

The settlement requires the installation and continuous operation of BACT-level controls at the CEMEX Lyons plant to control emissions of NOx. CEMEX will be required to install and continuously operate a selective non-catalytic reduction system (SNCR) on the Lyons kiln. Following the startup and optimization period, CEMEX will continuously operate the control technology to demonstrate its effectiveness for 365 days. During this demonstration period, CEMEX will be required to comply with an interim 30-day rolling average emission rate of 3.11 lb NOx/ton clinker. Following the demonstration period, CEMEX will submit a demonstration report with a proposed 30-day rolling average NOx emission rate. The EPA will either approve the proposed rate or establish an alternate final emission rate for the kiln based upon an evaluation of the data collected during the demonstration period.

This “test and set” process has been used in a number of cement settlements (and in some other sectors, such as refineries) to establish limits. It is particularly useful where there is limited information about how a particular control technology will perform. Using the test and set process ensures that the lowest practical emission limit at a particular unit will be achieved.

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Pollutant Reductions

In this case, the final rate established using the test and set process could result in as much as 1,200 tpy of additional NOx reductions. The test and set process guarantees that the settlement will reduce emissions by at least 870 tons per year.

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Health and Environmental Effects

The pollutants reduced under this settlement have numerous adverse environmental and health effects. Nitrogen oxides can be converted to fine particulate matter once in the air. Fine particulates can be aspirated and can lodge 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:

  • 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, 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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Civil Penalty

CEMEX will pay a total of $1.0 million in civil penalties.

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Comment Period

The proposed settlement, lodged in the U.S. District Court for the District of Colorado, 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 G. Klepp
U.S. Environmental Protection Agency
1200 Pennsylvania Ave., N.W.
Washington, DC 20460
(202) 564-5805

Shaun Burke
Senior Environmental Engineer
U.S. Environmental Protection Agency
1200 Pennsylvania Ave., N.W.
Washington, DC 20460
(202) 564-139

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