Chicago, Illinois - Monday, the U.S. Department of Justice and the U.S. Environmental Protection Agency (EPA) announced a settlement that requires Aux Sable Liquid Products LP (Aux Sable) to strengthen air pollution controls and reduce air pollution at its natural gas processing facility, located southwest of Chicago. The facility, which is the largest natural gas processing plant in the United States, is located within the Chicago Non-Attainment Area for ground-level ozone, which includes the greater Chicago area and the northwest Indiana counties of Lake and Porter.

Under the terms of the settlement, Aux Sable will pay a $2.7 million civil penalty and at least $4.5 million on improvements to pollution controls and projects to reduce volatile organic compounds (VOCs) and nitrogen oxide emissions (NOX).

“Today’s settlement appropriately enforces and resolves significant violations of the Clean Air Act by Aux Sable,” said Acting Assistant Attorney General Jeffrey H. Wood for the Justice Department’s Environment and Natural Resources Division. “The important upgrades at Aux Sable facility – required by today’s action -- will improve air quality in the Chicago area.  The Department of Justice continues to work with EPA to protect clean air for all Americans.”  

“The settlement reached today will result in cleaner air for communities in the Greater Chicago area by reducing emissions of pollutants that are ozone precursors,” said Assistant Administrator Susan Bodine for EPA’s Office Of Enforcement and Compliance Assurance. “This work required under the settlement will not only achieve compliance with the Clean Air Act, it also will advance EPA’s goal of reducing the number of nonattainment areas in the country.”

This settlement addresses alleged violations of the Clean Air Act’s New Source Review Rules for excess fugitive emissions of VOCs.  The Department of Justice and EPA allege that VOC emissions from equipment leaks at the facility have significantly exceeded the applicable thresholds for such emissions since the facility began operating in 2000, and Aux Sable has therefore never complied with the New Source Review requirements, including the lowest achievable emission rate and emission offset standards.  

In this settlement, Aux Sable has agreed to take measures to reduce its emissions of VOCs, including (1) expanding its fugitive emission leak detection and repair program to cover thousands of fittings at its facility; (2) complying with a more stringent leak threshold for making repairs to valves throughout the facility; (3) installing state-of-the-art “low-emissions” technology to replace or repack older leaking valves; (4) achieving 99 percent control efficiency of VOC emissions at the facility’s off-gas incinerators; (5) complying with flare operation monitoring requirements; and (6) installing ultra-low oxides of nitrogen (NOx) burner technology at the facility’s two process heaters.  EPA estimates that Aux Sable will spend at least $1.5 million in capital costs and at least $250,000 per year in incremental operational and maintenance costs to complete these improvements. 

Additionally, Aux Sable has addressed its noncompliance with the Illinois volatile organic material emission trading program by purchasing from the Illinois EPA the necessary VOC emission allotments and required emission excursion compensation to cover VOC emission-allotment deficiencies from 2001 to 2015, at a cost of more than $156,000. Aux Sable also submitted to Illinois corrections to past annual emission reports.

To mitigate the environmental harm caused by its Clean Air Act violations, Aux Sable has agreed to implement mitigation projects to reduce VOC and NOX emissions at locomotive switchyards located in the Chicago Area, which will include repowering switcher locomotives and installing switcher locomotive idle-reduction technology. Aux Sable will spend $3 million to implement these projects.

VOCs include a variety of chemicals that may produce adverse health effects such as eye, nose, and throat irritation, headaches, nausea, and damage to the liver, kidney, and the central nervous system. VOCs also contribute to the formation of ground level ozone. Breathing ozone can trigger a variety of health problems, particularly for children, the elderly, and anyone with lung diseases such as asthma. Ground level ozone can also have harmful effects on sensitive vegetation and ecosystems. Besides ground level ozone, NOx emissions also contribute to acid rain, particulate matter, water quality deterioration, and visual impairment.

The consent decree has been lodged with the U.S. District Court for the Northern District of Illinois and is subject to public comment for a period of at least 30 days. Notice of the lodging of the consent decree will appear in the Federal Register, allowing for a 30-day public comment period before the consent decree can be entered by the court as final judgment.