Report Exposes Vast Amounts of Unregulated Water Pollution from Oil Refineries

EPA Must Strengthen Pollution Limits for Refineries, as Required by Federal Law, and Penalize Violations of Existing Law 

For a copy of the report, click here.

For audio of the press conference, click here for part 1, and click here for part 2.

Washington, D.C. – A national study of water pollution from oil refineries reveals that EPA is failing in its legal responsibilities to regulate the half billion gallons of wastewater a day that pours out of U.S. refineries, loaded with nitrogen, industrial salts, cyanide, arsenic, chromium, selenium, and other pollutants.

Eighty-one refineries across the U.S. that discharge to waterways released 1.6 billion pounds of chlorides, sulfates, and other dissolved solids (which can be harmful to aquatic life) in 2021, along with 60,000 pounds of selenium (which can cause mutations in fish), and 15.7 million pounds of algae-feeding nitrogen (as much as from 128 municipal sewage plants), among other pollutants, according to public records examined by the Environmental Integrity Project in its report “Oil’s Unchecked Outfalls.”

The federal Clean Water Act requires EPA to set limits for pollutants from industrial sources and update them at least every five years as treatment technologies improve. But EPA has never set any limits for refinery discharges of many pollutants, including selenium, benzene, cyanide, mercury, and many others. And EPA has also failed to update the few limits that were established nearly four decades ago, in 1985.

“Oil refineries are major sources of water pollution that have largely escaped public notice and accountability in the U.S., and too many release a witches’ brew of contaminants to our rivers, lakes and estuaries. This is because of lax federal standards based on wastewater treatment methods that are nearly forty years old,” said Eric Schaeffer, Executive Director of the Environmental Integrity Project. 

“The Clean Water Act requires EPA to impose more stringent standards that reflect the advanced wastewater treatment methods available today. After decades of neglect, EPA needs to comply with the law and set strong effluent limits for refineries that protect public health and environment,” said Schaeffer, former Director of Civil Enforcement at EPA. “EPA and the states also need to start enforcing the limits that exist and penalizing polluters.”

For a copy of EIP’s report, “Oil’s Unchecked Outfalls,” click here. For a detailed spreadsheet showing pollution levels from all 81 U.S. refineries studied, click here.

One of the report’s conclusions is that much of the water pollution from oil refineries today is legal, because EPA and most states have failed to regulate it. But illegal pollution is also a major problem.

EIP’s review of EPA enforcement and compliance data found that almost 83 percent of U.S. refineries (67 of 81) reported violating their permitted limits on water pollutants at least once between 2019 to 2021. But less than a quarter of the refineries with violations (15 of the 67) were penalized during this period.

Among other conclusions of EIP’s report are the following:

  • Wastewater discharged by 68 percent of the refineries examined (55 of 81) contributes to the “impairment” of downstream waterways – meaning they are too polluted to support aquatic life or allow for recreational uses like swimming or fishing.
  • U.S. refineries are often old – averaging 74 years, but some dating back to the 1880’s – and many have antiquated and inadequate pollution control systems. Most have also expanded over the last forty years, increasing both the volume and variety of pollutants they discharge. But EPA has not updated its standards for refineries since 1985.
  • Two-thirds of the refineries examined by EIP (56 of 81) are located in areas where the percentage of low-income households within three miles exceeds the national average, and over half are located in areas where the percentage of people of color exceeds the national average.
  • Sixty-seven refineries were flagged by EPA as violating permitted pollution limits 904 times between 2019 and 2021, including for dumping excessive amounts of cyanide, zinc, total suspended solids, ammonia, and oil and grease.

The table below lists the worst refineries in the U.S. for water pollution for key pollutants.


Rank Refinery Name State Flow (MGD) Avg. Daily Discharge (lb/d) Load (lb/yr)
Selenium 1 Chevron El Segundo Refinery CA 8.9 14.4 5,257.2
2 Motiva Port Arthur Refinery TX 16.6 12.3 4,499.4
3 BP Whiting Refinery IN 18.4 9.8 3,589.1
4 Flint Hills Pine Bend Refinery MN 2.4 7.9 2,874.8
5 Citgo Lemont Refinery IL 6.0 7.0 2,547.6
6 Phillips 66 Wood River Refinery IL 9.5 6.0 2,176.4
7 TotalEnergies Port Arthur Refinery TX 5.2 5.4 1,976.8
8 Marathon Garyville Refinery LA 5.2 5.3 1,950.6
9 ExxonMobil Joliet Refinery IL 10.5 5.1 1,854.5
10 ExxonMobil Baton Rouge Refinery LA 14.5 4.7 1,709.2
Nickel 1 Phillips 66 Wood River Refinery IL 9.5 4.7 1,706.6
2 BP Cherry Point Refinery WA 4.2 2.4 869.1
3 ExxonMobil Baytown Refinery TX 29.6 2.1 777.0
4 Marathon Garyville Refinery LA 5.2 1.7 606.0
5 Chevron Richmond Refinery CA 7.1 1.4 528.8
6 Pemex Deer Park Refinery TX 11.1 1.4 525.1
7 Phillips 66 Lake Charles Refinery LA 5.8 1.0 357.0
8 PBF Delaware City Refinery DE 8.7 1.0 351.0
9 Chevron El Segundo Refinery CA 8.9 0.8 287.8
10 PBF Martinez Refinery CA 5.4 0.7 270.0
Nitrogen 1 Chevron El Segundo Refinery CA 8.9 4,351 1,588,015
2 PBF Delaware City Refinery DE 8.7 3,283 1,198,371
3 Motiva Port Arthur Refinery TX 16.6 2,110 770,253
4 Citgo Lemont Refinery IL 6.0 1,916 699,411
5 BP Whiting Refinery IN 18.4 1,573 574,008
6 Phillips 66 Bayway Refinery NJ 8.8 1,537 561,052
7 Phillips 66 Wood River Refinery IL 9.5 1,465 534,798
8 Citgo Lake Charles Refinery LA 8.9 1,421 518,668
9 Phillips 66 Alliance Belle Chasse Refinery LA 2.1 1,299 474,279
10 PBF Chalmette Refinery LA 16.5 1,201 438,476
Total Dissolved Solids 1 ExxonMobil Baytown Refinery TX 29.6 347,345 126,920,840
2 Valero Corpus Christi Bill Greehey TX 4.8 291,527 106,555,473
3 ExxonMobil Beaumont Refinery TX 15.5 283,944 103,705,967
4 Motiva Port Arthur Refinery TX 16.6 214,204 78,140,427
5 Phillips 66 Wood River Refinery* IL 9.5 188,131 68,685,462
6 ExxonMobil Baton Rouge Refinery** LA 14.5 150,739 55,012,480
7 Marathon Galveston Bay Refinery TX 14.1 149,666 54,670,585
8 TotalEnergies Port Arthur Refinery TX 5.2 141,893 51,791,099
9 Shell Norco Refinery LA 12.6 112,896 41,184,572
10 Phillips 66 Sweeny Refinery TX 5.9 107,342 39,291,921

*Reflects sum of sulfates and chlorides, Total Dissolved Solids (TDS) data unavailable. **Reflects sulfates only, TDS and chloride data unavailable. Note: Top dischargers in the table above are based on discharges of primarily process wastewater. See methods for detailed explanation. Source: Discharge monitoring data available through EPA’s ECHO database, TRI, and permit documents.

The following table identifies the 10 refineries that had the most frequent permit violations according to EPA’s Enforcement and Compliance History Online database and facility discharge monitoring reports, and how seldom they were penalized.


Refinery Name State Number of Effluent Limit Exceedances, 2019 – 2021 Number of CWA Enforcement Actions, 2019-2021 Penalties Collected, 2019-2021 (dollars)
1 Hunt Southland Refinery MS 144 2 $85,500
2 Phillips 66 Sweeny Refinery TX 44 1 $30,000
3 CountryMark Mount Vernon Refinery IN 40 0 0
4 ExxonMobil Joliet Refinery IL 40 0 0
5 Delek El Dorado Refinery AR 39 1 $15,100
6 Calumet Shreveport Refinery LA 32 2 $34,956
7 Cross Oil Refining Smackover Refinery AR 27 1 0
8 Chevron Richmond Refinery CA 27 0 0
9 WRB Refining Borger Refinery TX 26 0 0
10 Citgo Corpus Christi Refinery TX 25 0 0

Source: EPA’s Enforcement and Compliance History Online (ECHO) database and discharge monitoring data available through ECHO.  Possible permit violations flagged by EPA in this chart do not mean these companies have been charged with criminal or civil violations or convicted in court. (CWA = Clean Water Act)

Among the more frequent violators was the Phillips 66 Sweeny Refinery south of Houston, which exceeded its permitted pollution limits 44 times from 2019 to 2021, but was penalized just $30,000, according to EPA records.  Forty-two of the refinery’s 44 violations were for cyanide pollution in excess of permitted limits.

PFAS OR “FOREVER CHEMICALS” FROM REFINERIES: EIP’s report found that refineries are a notable source of “forever chemicals” (PFAS or per- and polyfluoroalkyl substances), in part because refineries often use these chemicals in firefighting foams. But EPA has set no limits on these chemicals in refinery wastewater, even though they have been linked to increased risk of endocrine (hormone) disruption, cancer, and other health problems.

The few refineries in the U.S. that have begun sampling for PFAS have seen the chemicals at high levels in their wastewater and runoff. For example, wastewater at the Suncor refinery in Commerce City, Colorado, had a concentration of 290 parts per thousand (ppt) of PFOS (one variety of PFAS) in May 2020, which was more than 14,000 times higher than EPA’s health advisory for PFOS in drinking water.  The levels were even higher at the Valero Benicia Refinery in Benicia, California, in October 2021, when sampling showed a concentration of 2,000 ppt PFOS.  This report suggests that this problem requires more investigation.


CALIFORNIA: Sejal Choksi-Chugh, Executive Director of San Francisco Baykeeper: “It’s high time for EPA to crack down on the toxic pollution from oil refineries that’s threatening both wildlife and human health around San Francisco Bay, and across the country. It’s offensive to our frontline communities that EPA has failed to require refineries to reduce the amount of many pollutants that they dump into the Bay, let alone regulate them.”

Bruce Reznik, Executive Director, Los Angeles Waterkeeper: “Once again, the U.S. Government has turned a blind eye while oil and gas companies pollute our environment, including our sensitive marine ecosystems, and disproportionately harm our frontline communities.  We must now put the spotlight on oil refineries’ essentially unregulated water pollution and demand that EPA fulfill its duty under the Clean Water Act by setting, updating, and actually enforcing discharge limits for these refineries.”

TEXAS: Kristen Schlemmer, Legal Director & Waterkeeper, Bayou City Waterkeeper: “This report reinforces what we all know: For far too long, Houston and the Gulf as a whole have been treated like a sacrifice zone, with the greatest burdens falling on low-income Black and brown communities, including those living along the Houston Ship Channel. In this case, the answer is straightforward: EPA must update long-outdated rules to account for the realities of the 21st century and act to hold polluters accountable to these rules through consistent enforcement. To do anything less would be to abandon EPA’s commitment to environmental justice and, once again, leave behind the most vulnerable communities across Houston and the Gulf.”

ILLINOIS: Mitch McNeil, Chair of the Surfrider Foundation Chicago Chapter: “It’s vital that refineries are held accountable for violations that pollute our water commons, and that regulators are accountable for regulating them and protecting our water.  People who drink the water, play in the water, and eat fish from Lake Michigan and other waters bordered by refineries have a right to be able to do so without endangering their health.”

DELAWARE: Brian Moran, Chair Surfrider Foundation Delaware Chapter: “We are concerned with the amount and types of pollutants released by the refinery. Pollution in the river can have an impact downstream on our wetlands, bay, and ocean. The state and EPA need to protect our coast and deny PBF Energy’s permit renewal until improvements are made to stop the contamination of the river.”

The Environmental Integrity Project is a 21-year-old nonprofit organization, based in Washington, D.C. and Austin, Texas, dedicated to enforcing environmental laws and strengthening policy to protect public health and the environment.

Media contact: Tom Pelton, Environmental Integrity Project (443) 510-2574 or