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Western Refining Clean Air Act Settlement

Overview of Company and Location of Facility

Western Refinery, owned by Western Refining L.P., is an 116,000 barrel-per-day (bpd) refinery located in El Paso, Texas. Western Refining, with headquarters in El Paso, is an independent oil refiner and marketer operating primarily in the Southwestern and Mid-Atlantic parts of the United States. In addition to the El Paso facility, the company has refineries near Gallup, N. M. and in Yorktown, Va., both of which are covered under separate Petroleum Refinery Initiative settlement agreements, the Yorktown refinery is covered by the BP settlement and the Gallup refinery is covered by the Giant settlement.

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The complaint alleges violations of Clean Air Act requirements covering the four main sources of emissions sulfur dioxide (SO2), nitrogen oxides (NOx), volatile organic compounds (VOCs) and benzene:

  • New Source Review/Prevention of Significant Deterioration (NSR/PSD), 40 C.F.R. Part 52
    • Fluidized Catalytic Cracking Unit (FCCU)
    • Refinery Heaters and Boilers
  • New Source Performance Standards (NSPS), 40 C.F.R. Part 60, Subparts A, J & Ja
    • Flares
    • Sulfur Recovery Units
    • Fuel Gas Combustion Devices (including heaters & boilers)
  • Leak Detection and Repair (LDAR), 40 C.F.R. Part 60, Subpart GGG
  • National Emission Standards for Hazardous Air Pollutants (NESHAP) for benzene wastes, 40 C.F.R. Part 61, Subpart FF

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Injunctive Relief

The consent decree requires the following actions at an estimated cost of $60 million:

New Source Review/Prevention of Significant Deterioration (NSR/PSD) -- FCCU and Heaters and Boilers

  • FCCU NOx limits of not more than 55 parts per million (ppm) (365-day) and 100 ppm (7-day) effective upon the Date of Entry (DOE) of the Consent Decree. The final NOx limit of 50 ppm (365-day) and 90 ppm (7-day) must be met within 1 year of DOE
  • FCCU SO2 limits of 25 ppm (365-day) and 50 ppm (7-day) effective upon DOE
  • Existing NOx and SO2 continuous emission monitors (CEMs) will be used to demonstrate compliance with the Consent Decree limits
  • Particulate emissions limits of 0.5 pound per 1,000 pounds coke burned will be met at the FCCU
  • Carbon monoxide emission limit of 500 ppm on a 1-hour average basis and 100 ppm on a 365-day rolling average basis
  • Installation of controls (Ultra Low NOx Burners, Selective Catalytic Reduction, or other technology) sufficient to achieve a system-wide NOx reduction of 481 tons per year (tpy) at all heaters and boilers
  • Compliance with NSPS Subpart J at all heaters and boilers
  • Restrictions on fuel oil burning in heaters to control SO2
  • Net reductions of 257 (tpy) of SO2 from the shutdown of the two sulfur recovery plants and the permitted emissions of the sulfuric acid plant

New Source Performance Standards (NSPS) and Flaring

  • All refinery flares subject to NSPS Subpart J as of DOE. Compliance with all aspects of NSPS Subpart J for two of the three refinery flares as of DOE and the third 120 days after DOE.
  • Installation of Flare Gas Recovery Systems on two of the refinery's three flares.
  • A "root cause" analysis and corrective action for all future flaring events.

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Benzene Waste Operations National Emissions Standards for Hazardous Air Pollutants (NESHAP)

  • Compliance with the "6 MQ" compliance option for refineries with total annual benzene (TAB) greater than 10 Mg/yr
  • Review and verification of benzene-producing waste streams to ensure that benzene is properly accounted for and managed
  • Comprehensive "management of change" procedures to ensure that newly created benzene streams are included in the TAB calculation
  • Mandatory laboratory audits
  • Quarterly sampling and TAB calculation
  • Training for those who sample benzene

Leak Detection and Repair (LDAR) Program

  • Refinery-wide compliance with LDAR requirements
  • Training, including refresher courses, for refinery personnel with LDAR responsibility
  • Mandatory periodic LDAR compliance audits
  • Strict internal leak definitions (500 ppm for valves and 2000 ppm for pumps)
  • Internal "first attempt at repair" at 200 ppm for valves
  • More frequent monitoring than required by regulation

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Pollutant Reductions

When all required controls have been installed and implemented, this settlement is estimated to result in the following emissions reductions:

  • NOx reduced by 509 tons per year (tpy)
  • SO2 reduced by 381 tpy
  • Additional unspecified reductions of VOCs, PM and CO

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Health and Environmental Effects

  • 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.
  • 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.
  • Volatile Organic Compounds - VOCs, along with NOx, play a major role in the atmospheric reactions that produce ozone, which is the primary constituent of smog. People with lung disease, children, older adults, and people who are active can be affected when ozone levels are unhealthy. Ground-level ozone exposure is linked to a variety of short-term health problems, including lung irritation and difficulty breathing, as well as long-term problems, such as permanent lung damage from repeated exposure, aggravated asthma, reduced lung capacity, and increased susceptibility to respiratory illnesses such as pneumonia and bronchitis.
  • Benzene - Acute (short-term) inhalation exposure of humans to benzene may cause drowsiness, dizziness, headaches, as well as eye, skin, and respiratory tract irritation, and, at high levels, unconsciousness. Chronic (long-term) inhalation exposure has caused various disorders in the blood, including reduced numbers of red blood cells and anemia in occupational settings. Reproductive effects have been reported for women exposed by inhalation to high levels, and adverse effects on the developing fetus have been observed in animal tests. Increased incidences of leukemia have been observed in humans occupationally exposed to benzene. EPA has classified benzene as a Group A human carcinogen (proven carcinogenicity).

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Civil Penalty

Western will pay a $1.45 million civil penalty to the United States.

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Comment Period

The proposed settlement is lodged in the U.S. District Court for the Western District of Texas. The consent decree will be subject to a 30-day public comment period and final court approval. Information on submitting comments is available at the Department of Justice website.

Petroleum Refinery National Initiative Case Results

Through multi-issue, multi-facility settlements or detailed investigations and aggressive enforcement, this national priority addresses the most significant Clean Air Act compliance concerns affecting the petroleum refining industry.

See EPA's National Petroleum Refining Initiative website for more information.

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For more information, contact:

Patrick W. Foley
Senior Environmental Engineer
U.S. Environmental Protection Agency (2242A)
1200 Pennsylvania Ave., N.W.
Washington, DC 20460-0001
(202) 564-7978

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