An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »


CITGO Petroleum Corporation and PDV Midwest Refining, LLC Settlement

(Washington, DC - November 10, 2016) CITGO Petroleum Corporation and PDV Midwest Refining, LLC (collectively, CITGO) have agreed to pay a $1,955,000 civil penalty, perform environmental projects totaling more than $2 million, and spend an estimated $42 million in injunctive relief to resolve Clean Air Act violations and violations of CITGO’s global refinery consent decree at its refinery, located in Lemont, Illinois. Once fully implemented, the controls required by this settlement are estimated to reduce emissions of harmful air pollution that can cause respiratory problems, such as asthma, and that are significant contributors to acid rain, smog, and haze by approximately 470 tons per year. The settlement will also reduce greenhouse gas emissions from the refinery, estimated at approximately 10,850 tons per year of reductions in carbon dioxide equivalent.

On this page:

Overview of Company and Location of Facility

CITGO claims a total refining capacity of approximately 750,000 barrels of crude oil per day, 167,000 barrels of which is attributed to the Lemont refinery. CITGO is also one of the largest suppliers of petrochemicals in the nation; its products are primarily sold through independent marketers. The Lemont refinery is located on 900 acres that span Lemont and Romeoville, Illinois. The Lemont refinery’s operations are capable of refining heavy, sour crude oils into finished products, such as various grades of gasoline, diesel, jet fuel, and hydrocarbon solvents.


The settlement resolves alleged violations of Clean Air Act requirements, as well as requirements of CITGO’s global refinery consent decree, at the Lemont refinery:

  • Heaters:  A CITGO global refinery consent decree prohibition against the use of emission reductions resulting from that decree as netting credits and, consequently, New Source Review (NSR) permitting requirements at a number of heaters;
  • Fluid Catalytic Cracking Unit :  A CITGO global refinery consent decree PM emission limit, 40 C.F.R. Part 60, Subparts A (General Provisions) and J (Standards of Performance for Petroleum Refineries), and NSR permitting requirements;
  • Sulfur Recovery Plant (SRP):  A CITGO global refinery consent decree requirement to route or re-route all sulfur pit emissions to eliminate, control, or include and monitor them as part of the SRP’s emissions;
  • Continuous Emissions Monitoring Systems (CEMS) Downtime:  Violations relating to requirements for continuous operation of a number of CEMS, specifically requirements found at 40 C.F.R. Part 60, Subparts A and J, and in the CITGO global refinery consent decree;
  • Benzene-Containing Process Fluid Samples:  40 C.F.R. Part 63, Subpart H (the HON Rule) for failure to control emissions from benzene samples and purged process fluids from vacuum truck pump exhaust where vacuum trucks are used to collect such liquids and transport for disposal;
  • Flares:  Violations relating to flare operation, specifically violations of the Illinois State Implementation Plan and 40 C.F.R. Part 60, Subpart GGG (Standards of Performance for Equipment Leaks of VOC in Petroleum Refineries); and
  • Leak Detection and Repair (LDAR):  Violations relating to LDAR requirements, specifically violations of 40 C.F.R. Part 60, Subparts VV (Standards of Performance for Equipment Leaks of VOC in the Synthetic Organic Chemicals Manufacturing Industry) and GGG, and requirements found in the CITGO global refinery consent decree.

Top of Page

Injunctive Relief 

This settlement requires the following actions at the Lemont refinery, at an estimated cost of $42 million.


  • Nitrogen oxides (NOx) emissions reductions through installation of low-NOx burners at three heaters;
  • NOx emission limits at those three heaters reflective of the new controls, and reduced limits at two additional heaters already using low-NOx burners; and
  • Use of CEMS or parametric monitoring systems (PEMS) to demonstrate compliance with those emission limits.

Fluid Catalytic Cracking Unit:

  • Particulate matter (PM) emission limit of 0.5 pounds of PM per 1000 pounds of coke burned on a 3-hour average basis; and
  • Provisions for root cause analyses, corrective actions, and third party evaluations if the FCCU’s PM control device experiences abnormal operation.

Sulfur Recovery Plant:

  • Operation and maintenance (O&M) plan to ensure good air pollution control practices for minimizing emissions.

Continuous Emissions Monitoring Systems Downtime:

  • O&M plan to minimize periods of CEMS and PEMS downtime; and
  • Provisions for root cause analyses, corrective actions, and third party evaluations if CEMS or PEMS downtime exceeds five percent in any two consecutive calendar quarters.

Benzene-Containing Process Fluid Samples:

  • Use of carbon canisters for emissions control on all vacuum trucks used for collection and transportation of purged process fluids subject to the HON Rule.


  • Installation of additional flare gas recovery system (FGRS) capacity for the two highest volume flares at the Lemont refinery;
  • Up-time requirements for the new FGRS compressor, as well as for the Lemont Refinery’s existing FGRS compressors;
  • Efforts at flare minimization, including waste gas characterization and mapping to determine the source and quantity of flared gas to identify opportunities for reducing waste gas;
  • A refinery-wide cap on flared waste gas, and individual flare caps for two flares;
  • 40 C.F.R. Part 60, Subparts A and Ja applicability at all Lemont refinery flares; and
  • 40 C.F.R. Part 63, Subpart CC applicability for all Lemont refinery flares, except the C4 Flare, which does not receive hazardous air pollutants (HAP) emissions.

Leak Detection and Repair:

  • 40 C.F.R. Part 60, Subpart GGGa applicability at each process unit at the Lemont Refinery; and
  • Implementation of an enhanced LDAR program, including third-party refinery-wide LDAR audits, reduced thresholds for leak definitions, increased monitoring frequency, and a requirement to use low emission technology for newly installed valves and replacement or repacking of existing valves.

Top of Page

Environmental Mitigation Projects

CITGO will reduce benzene and volatile organic compound (VOC) emissions by installing controls for a benzene-containing waste stream that is currently uncontrolled (and not required to be controlled for the Lemont refinery to comply with applicable regulations, including the National Emission Standard for Benzene Waste Operations at 40 C.F.R. Part 61, Subpart FF). Controlling the waste stream will require CITGO to install approximately 800 feet of heat-traced piping and install and operate a pump and control valve to allow for control of the discharge rate. CITGO estimates that it will spend approximately $1.14 million to complete this project.

Top of Page

Supplemental Environmental Projects

The consent decree requires CITGO to spend $1 million on two supplemental environmental projects (SEPs) as follows: $650,000 on a fence line monitoring system for the Lemont Refinery; and $350,000 on a green lighting project in the local school district.

The fence line monitoring system will include two monitoring stations to continuously measure benzene, hexane, and hydrogen sulfide (H2S) concentrations, along with measurement and recording of meteorological parameters (i.e. wind speed, wind direction, etc.). If the fence line monitoring system detects concentrations above certain levels with wind data indicating the emissions may be originating from the Lemont Refinery, then CITGO will be required to investigate the source of the emissions and take corrective actions. The fence line monitoring system project requires use of a portable photo-ionization detector and infrared gas-imaging camera to survey both process unit equipment and storage tanks as possible sources of benzene and hexane emissions.

The green lighting project is intended to reduce emissions of carbon dioxide (CO2), sulfur dioxide (SO2), and NOx through the conversion of certain lighting fixtures into more-efficient, lower-watt, LED lighting fixtures. All lighting conversions will be performed on facilities owned and operated by the Lemont-Bromberek Consolidated School District.

Top of Page

Pollutant Reductions

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

  • 170 tons of SO2 per year (tpy)
  • 170 tpy of VOCs
  • 90 tpy of NOx
  • 40 tpy of PM
  • 10,850 tpy of CO2e
  • Additional reductions of VOCs and HAPs, including benzene, are expected as a result of compliance with the settlement’s LDAR requirements and requirements for control of benzene-containing process fluid samples.
  • The surrounding community will also benefit from emissions reductions achieved through the above-described environmental mitigation project and the two supplemental environmental projects.

Top of Page

Health and Environmental Effects

  • 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.
  • 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.
  • Particulate Matter - Particle pollution, especially fine particles, contains microscopic solids or liquid droplets that are so small that they can get deep into the lungs and cause serious health problems. Exposure to such particles can affect both the lungs and heart. Numerous scientific studies have linked particle pollution exposure to a variety of problems, including premature death in people with heart or lung disease, nonfatal heart attacks, irregular heartbeat, aggravated asthma, decreased lung function, and increased respiratory symptoms, such as irritation of the airways, coughing, or difficulty breathing. People with heart or lung diseases, children, and older adults are the most likely to be affected by particle pollution exposure. However, even if you are healthy, you may experience temporary symptoms from exposure to elevated levels of particle pollution.
  • 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. The EPA has classified benzene as a Group A human carcinogen.

Top of Page

Civil Penalty

CITGO will pay a $1,955,000 civil penalty to the United States. 

Comment Period

The proposed settlement is lodged in the U.S. District Court for the Northern District of Illinois.  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 (DOJ) 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.

For more information, contact:

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

Legal Contact
Virginia A. Sorrell, Attorney
U.S. Environmental Protection Agency (8MSU)
1595 Wynkoop St.
Denver, CO 80403
(303) 312-6669

Top of Page