Frigid weather this month caused industrial facilities across Texas to release unplanned air pollution as machinery froze, power went out and icy conditions blocked service crews. 

Over four chilly days between Jan. 14 and 17, companies submitted reports to Texas’ environmental regulator, the Texas Commission on Environmental Quality, that  

attributed at least 36 instances of “unintentional” emissions to the freezing temperatures. 

According to the companies’ preliminary estimates, those incidents collectively produced more than a million pounds of air pollution. That’s a small figure compared with the massive volumes of permitted emissions released every day across this large, industry-heavy state. But the reports illustrate the sensitivity of facilities to the weather and expose a long-standing loophole in environmental enforcement that allows companies to exceed permitted emissions limits without consequence under certain conditions. 

“Polluters continue to skimp on weatherization, which leads to big pollution dumps during extreme cold and hot weather,” said Luke Metzger, executive director of the nonprofit Environment Texas, which compiled and analyzed the recent freeze-related emission reports. 

It’s typical to see pollution spikes during extreme weather, from arctic blasts to tropical storms and heat waves. Metzger and other public health advocates in Texas say companies and regulators could do more to reduce unplanned emissions.

Carolina Espinosa, a spokesperson for the Texas Chemistry Council, which represents over 200 facilities in the chemical manufacturing industry, said companies have done “extensive winterization” to “safeguard against impacts from the weather.” Still, she acknowledged that during severe weather, electricity outages or other supply chain disruptions “may result in unplanned emissions.” 

In one incident last week, Formosa Plastics Corp. burned off large volumes of ethylene, a chemical with a faint sweet and musky odor, at its massive Lavaca Bay complex. Other nearby plants that typically purchased Formosa’s ethylene had gone offline and closed their pipelines, forcing the company to dispose of the product. 

“Due to extreme cold weather and loss of downstream Ethylene users… Ethylene production had to be flared,” Formosa, a Taiwanese company, reported to the TCEQ. Flaring is a process for burning unwanted gas to relieve pressure or clear pipes. 

Formosa estimated that it released 64,800 pounds of unburned ethylene emissions from one flare over 24 hours — 79 times the unit’s permitted limit. From another flare, Formosa estimated emissions of 38,400 pounds — almost 500 times its permitted limit. In all, Formosa blamed the weather, which ranged from 24 to 51 degrees, for almost 250 tons of air pollution composed of more than 40 chemicals on Jan. 17.

A spokesperson for Formosa, Amy Blanchett, said the company doesn’t comment on operational issues “unless we anticipate a substantive impact on the marketplace.”

Three days prior and 450 miles away, a maintenance device got stuck in a Permian gas pipeline. When operators with ET Gathering & Processing went to retrieve it, they opted to release 205,000 pounds of methane, a climate super-pollutant 80 times more warming than carbon dioxide, rather than burning it off, despite lacking specific authorization to do so, according to the company’s report to TCEQ.

“Due to time constraints from incipient winter weather conditions it was decided to blow down to atmosphere rather than blowing down to a flare,” the report said. 

Across the state in Longview, at the Eastman Chemical Company, an open hatch on a storage tank was leaking benzene, a known human carcinogen, and couldn’t be shut while temperatures ranged between 11 degrees and 44 degrees on Jan. 17. 

“Due to icy weather conditions and other safety concerns, Operations is currently unable to access the hatch to close it,” the company wrote in its report to TCEQ.  

When inhaled in large quantities over a short period, benzene can affect the central nervous system and cause symptoms including dizziness, a rapid heart rate and headaches.

“Eastman takes seriously any release to the environment and evaluates these events as necessary to prevent recurrence,” said a company spokesperson, Jennifer Heronema. 

She added that the company “follows an established protocol to prepare for cold winter months,” which includes checking systems ahead of cold weather, and securing and draining portions of the plant to prevent freezing. 

“Upset” Emissions

Companies report their weather-related emissions to the TCEQ as “upset” events, defined in federal law as “unintentional and temporary noncompliance” with pollution standards “because of factors beyond the reasonable control of the Industrial User.” 

“Upsets” don’t include pollution releases “caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation,” according to the law.

According to environmental advocates, federal and state regulations are full of “loopholes” that let companies disregard permit limits and avoid liability for emissions from events described as “startups, shutdowns and malfunctions.”

“If you violate one of your limits because of an ‘emergency,’ it is ok. You didn’t break the law,” said Seth Johnson, an attorney for the nonprofit Earthjustice. 

However, he argued, the exemption was improper because “the Clean Air Act says you need to meet emission limits at all times.”

Enforcement of federal environmental law falls to state governments, which can choose how vigorously to scrutinize reported upset emissions.

A 2023 report by the Environmental Integrity Project found that industries in Texas reported thousands of upsets each year, but “in only one half of one percent of these incidents did the state use its legal authority to require the companies to analyze the cause of the problem and take concrete action to avoid these pollution releases in the future.”

A spokesperson for the TCEQ, Richard Richter, said “cold weather events may cause or contribute to emissions events for a wide range of reasons.” Refineries and chemical plants  may shut down or reduce operations “in order to prevent catastrophic failures that could occur due to weather,” he said.

When they do, they must file “emissions event” reports with the TCEQ, listing the estimated quantities of chemicals released along with a reason for the upset.

“Based on the results of an investigation of a reportable incident, TCEQ may pursue enforcement actions when appropriate,” Richter said. 

In 2022, 17 groups from Texas and beyond petitioned the EPA to close those loopholes in regulations it issues itself. Federal regulations provided at least 97 different exemptions for startups, shutdowns and malfunctions at the time, the petition said.  

Last year, the EPA took steps to limit which events can qualify as “upsets,” but they’re not likely to significantly reduce overall upset emissions. 

“There are free passes — loopholes — now. Many are being closed and the rest that remain open need to be closed,” said Johnson. “That’s necessary in order to urge companies to take sensible precautions to avoid being in these circumstances.” 

These loopholes present significant environmental justice issues because they produce extensive added pollution along the Houston Ship Channel, where many Black and brown communities face health risks from air hazards, advocates said. Under the new EPA rule, citizens can take polluters to court who exceed their permitted emission limits and release harmful pollutants into the air during malfunctions or emergency shutdowns.

Winter Weather Emissions 

Shutdowns and malfunctions are common during extreme weather like cold snaps, heat waves and hurricanes. 

Last summer, a record-breaking heat wave forced pipeline operators in the Permian Basin to vent almost a million pounds of methane gas, which they reported to TCEQ. In 2021, companies reported 3.5 million pounds of excess pollution during widespread blackouts and historic low temperatures caused by Winter Storm Uri.  

Last week in Corpus Christi, where temperatures ranged from 24 to 42 degrees, a Flint Hills Resources refinery released almost 17,000 pounds of sulfur dioxide after some of its units overpressured and shut down due to frigid temperatures. 

According to Andy Saenz, director of public affairs at the refinery, the company measured air quality with both fence line monitors and hand-held equipment following the event and found "no elevated emission readings at the fence line or in the community."

ExxonMobil also blamed the weather on Jan. 16 for 61,400 pounds of emergency carbon monoxide emissions over 24 hours from one flare at its Beaumont chemical plant — almost eight times the unit’s permitted emission rate. 

“Those flare emission numbers are really just ballpark estimates,” said Neil Carman, a former TCEQ investigator who now works as clean air director for the Sierra Club in Texas. “Companies are guesstimating what's going into the flare, but they do some fuzzy math calculations on what they think is coming out.”

The reported volumes of carbon monoxide emissions alone shouldn’t cause significant health impacts, said Daniel Cohan, an atmospheric scientist at Rice University. However, ExxonMobil also reported more hazardous substances in emissions from its Beaumont plant, including more than 2,000 pounds each of the known human carcinogens benzene and 1,3-butadiene. 

For these chemicals, “more than a thousand pounds is a problem,” Cohan said. “Air toxics, such as benzene, are directly harmful and can have a greater effect during winter than during some other seasons.”

That’s because gasses like benzene linger near ground level for longer in cold air than they do in warm air, Cohan said. 

More than 4,000 people live within two miles of Exxon’s Beaumont plant, according to the EPA’s environmental justice screening tool, 88% of them people of color. 

ExxonMobil spokesperson Lauren Knight said in an email that the company has winterized its equipment by inspecting pipes, adding insulation and "even proactively shutting down units when necessary." 

Knight said the company takes excess emission events seriously and will continue to work on how it responds to severe weather. 

TotalEnergies’ Port Arthur refinery and Equistar Chemicals’ La Porte plant both reported upset emissions due to power outages. Valero reported upset emissions at its Texas City refinery, as did Dow Chemical at its massive Freeport complex after low temperatures damaged its chemical products and they had to be burned off in flares.

Industrial operators can take steps to reduce weather-related pollution releases, said Dr. Inyang Uwak, research and policy director at the environmental nonprofit Air Alliance Houston. 

She said companies could install backup power to prevent sudden shutdowns, or gas recovery systems to capture chemicals that would otherwise be flared. And, she said, Texas regulators could more often penalize companies that violate permits, even during inclement weather. 

“It’s not a new thing, they need to prepare,” Uwak said. “They do not adequately protect for these weather events, so they end up releasing tons of harmful pollution into downwind communities.”