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Murphy Oil USA Clean Air Act Settlement

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Overview of Companies and Location of Facilities

Murphy Oil USA (Murphy) is a subsidiary of Murphy Oil Corporation, which owns and operates companies that conduct oil exploration activities worldwide and that produce oil and natural gas in the United States, Canada, the United Kingdom and Malaysia.

Murphy Oil USA, headquartered in El Dorado, Ark., owns and operates petroleum refineries in Meraux, La. and Superior, Wisc.

Murphy's refineries have a total refining capacity of 160,000 barrels per day (bbl/day), or just less than 1 percent of total U.S. domestic refining capacity, as follows:

  • Meraux, La. - 125,000 bbl/day
  • Superior, Wisc. - 35,000 bbl/day

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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 at each of the refineries:

  • New Source Review/Prevention of Significant Deterioration (NSR/PSD), 40 C.F.R. Part 52
    • Fluidized Catalytic Cracking Units (FCCUs)
    • 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 both refineries, at an estimated cost of $142 million:

New Source Review/Prevention of Significant Deterioration (NSR/PSD) -- Fluidized catalytic cracking units (FCCUs) and Heaters and Boilers

  • FCCU NOx limits of not more than 20 parts per million (ppm) on a 365-day rolling average basis and 40 ppm on a 7-day rolling average basis at the Meraux refinery. The Superior refinery will implement a program to demonstrate the lowest emissions achievable using NOx-reducing catalyst additives in conjunction with other operational requirements to minimize NOx emissions. The final NOx emissions limit at the Superior refinery will be no higher than 40 ppm on a 365-day rolling average and 80 ppm on a 7-day rolling average basis.
  • FCCU SO2 limits of 25 ppm on a 365-day rolling average basis and 50 ppm on a 7-day rolling average basis at both refineries.
  • Installation of NOx and SO2 continuous emission monitors.
  • Particulate emissions limits of 1.0 pound per 1,000 pounds coke burned at each refinery's FCCU.
  • Carbon monoxide emission limit of 500 ppm on a 1-hour average basis at each refinery's FCCU.
  • Installation of Selective Catalytic Reduction, Ultra Low NOx Burners, or equivalent technology that are designed to achieve an emission rate of 0.040 lb NOx/mmBTU (pound per million British thermal units of heat input) for heaters and boilers at each refinery greater than 40 MMBtu/hr.

New Source Performance Standards (NSPS) and Flaring

  • Compliance with SO2 standards of Subpart J for all combustion devices burning refinery fuel gas, including flares
  • Compliance with SO2 standards of Subpart Ja at all sulfur recovery processes, including the sulfur pit
  • Comply with NSPS Subpart A, General Provisions, 40 C.F.R. § 60.11 (d), by conducting root cause analyses for all flaring events exceeding 500 lb/day of SO2
  • Installation of a flare gas recovery system at the Meraux refinery
  • Installation of a caustic scrubber system for the sulfur recovery plant at the Superior refinery

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

  • Total annual benzene (TAB) less than 10 Mg/yr at the Superior refinery
  • Compliance with the EPA-preferred "6 BQ" benzene compliance option at the Meraux refinery
  • Modified management of change procedures to ensure that new benzene streams are included in the TAB calculation
  • Conduct 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
  • Required 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
  • Installation of "low-leaking" valve or valve packing technology in all new applications

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Pollutant Reductions

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

  • NOx emissions by 452 tons per year (tpy)
  • SO2 emissions by 944 tpy

The settlement will also result in additional reductions of particulate matter (PM), carbon monoxide, benzene and other pollutants.

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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.

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Civil Penalty

Murphy will pay a $1.25 million civil penalty as follows:

  • $625,000 to the United States
  • $229,687.50 to Wisconsin
  • $395,312.50 to Louisiana

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Supplemental Environmental and Other Community Projects

Murphy will undertake the following projects at the Meraux refinery:

  • A $1.5 million supplemental environmental project (SEP) to reduce VOCs by covering the refinery's two oil-water separators. The SEP is estimated to reduce VOC emissions by 1780 pounds per year.
  • Construction and operation of an ambient air monitoring station adjacent to the Meraux Refinery. Emissions data from the monitoring station and from refinery emission units will be on an internet website to be established and maintained by Murphy.
  • Regular monthly meetings held for residents of the neighborhood adjacent to the refinery.
  • Noise abatement and dust suppression measures.
  • Preservation of the historic Villere Plantation ruins.

In addition, if Murphy constructs a coking unit at the Meraux refinery, the consent decree mandates application of best available control technology requirements, including:

  • A coke drum depressurization standard of 2.0 pounds per square inch gauge to control VOCs and other pollutants.
  • An enclosed "coke pit" and coke conveyance system to control dust and PM.
  • An enclosed coker quench water system to control VOCs.

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State Partners

The states of Wisconsin and Louisiana participated in the settlement negotiations and are parties to the settlements.

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Comment Period

The proposed settlement is lodged in the U.S. District Court for the Western District of Wisconsin. 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.

This consent decree will replace a March 2002 settlement between the United States, the State of Wisconsin, and Murphy that covers only the Superior refinery.

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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 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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