A collection of environmental groups based in Washington, D.C., Texas and elsewhere has asked a federal judge to force the U.S. Environmental Protection Agency to revisit rules that control the operation of industrial flares at chemical plants, natural gas processing plants, landfills and other sites.

Burning like an outsized pilot light from under the hot water heater, industrial flares are a common feature on the horizon in many parts of southeast Louisiana.

Often visible from Interstate 10 and other highways linking communities along the Mississippi River, the flares can light up the night sky in places like Chalmette, Norco, Geismar and Baton Rouge with sometimes huge flames during so-called plant "upsets."

But these flares serve an important role. They often are the pollution control device of last resort at larger facilities, state and federal regulators say.

The hot flames destroy hazardous emissions with predicted 98% or even 99% efficiency, preventing hazardous air pollution. HAPs and VOCs, the chemicals flares destroy, can cause cancer and other serious health effects or contribute to smog.

Industrial air permits and state and federal air emissions rules are built around that flares effectively destroy pollutants. The D.C.-based Environmental Integrity Project and nine other groups allege in a new lawsuit, however, that the flares are being operated under outdated rules from the 1980s and early 1990s that result in the flares being run less efficiently than predicted. As a result, much more pollution is being sent into the air and onto fence-line communities than predicted, they claim.

As evidence, the environmental groups' suit has directed the EPA to its own conclusions from an earlier review of flare operations for a specific kind of petrochemical plant, an ethylene cracker, which makes building block chemicals for plastics. 

The EPA's own review found ethylene flares weren't reaching the predicted 98% destruction efficiency but something between 86.6% to 94.2% efficiency. The lawsuit says that means those facilities were releasing five times the predicted pollution. 

The lawsuit alleges that it's time for EPA to apply a similar analysis for other facilities that use flares, including other kinds of petrochemical operations, petroleum tank farms, natural gas processing plants and landfills, which have flares that burn off gases emitted from decomposing waste.

"It’s been far too long since EPA updated these industrial flare standards, and EPA is well aware of the problem," Adam Kron, an EIP senior attorney, said in a statement. "Time and time again over the past decade, EPA has admitted that flares operating under these outdated standards can release many times more toxic air pollutants into local communities than estimated. This can cause serious harm to public health."

EPA is supposed to review the rules every eight years under the Clean Air Act. But, while EPA has updated the rules for oil refineries and ethylene complexes, the agency hasn't updated the two sets of general flare rules since the mid-1980s and mid-1990s for other industries, the suit alleges.

The suit was filed Thursday in U.S. District Court for the District of Columbia against EPA Secretary Andrew Wheeler. EPA spokespersons in Dallas, Texas, declined to comment Friday on pending litigation. 

None of the plaintiffs in the suit, many of whom represent fence-line communities in other states, are from Louisiana. But, should they prevail and force EPA to reevaluate the rules, the suit could present a significant impact on Louisiana facilities up and down the Mississippi, in the Lake Charles area and elsewhere.

Officials with the state Department of Environmental Quality couldn't immediately provide Friday a precise number of flares that could be affected. 

"This is a lot of flares … probably the majority in the petrochemical industry and some in the natural gas processing industry," DEQ officials said in a statement.

Running the flares requires plants to find a kind of sweet spot. They have to be supplied with enough waste gases and kept hot enough to destroy dangerous chemicals but also must avoid the creation of dark, sooty smoke that creates harmful, fine particulate air emissions.

Operators often inject air or steam to keep smoke from forming, but that can lower the combustion temperature and hurt destruction efficiency if operators aren't careful. 

DEQ officials noted that, while it's hard to say what the EPA might make individual industry sectors do, the operators of ethylene facilities are having to follow new rules very close to what was adopted for oil refiners a few years beforehand. DEQ officials suggested EPA may be using the refinery rules as a template.

Among the changes, the new ethylene rules alter how, where and how often operators measure flares and also increase overall monitoring time. 

Nationwide, the changes for ethylene complexes alone are expected to cut hazardous air pollutant emissions by 1,430 tons per year and volatile organic compound emissions by 13,020 tons per year, EPA says.

The ethylene rules, which are expected to affect 31 existing or planned facilities nationwide, took effect in July and the companies have until 2023 to implement them. In Louisiana, they include Union Carbide in St. Charles Parish, Dow Chemical in Plaquemine, ExxonMobil Chemical in Baton Rouge, Sasol in Lake Charles and Shell Chemical in Norco.

The capital investments needed to make those changes are expected to reach $45.6 million nationwide, EPA says. 

Separately, in June 2018, ExxonMobil and EPA reached a consent decree that forced $300 million in upgrades to flares at its Baton Rouge chemical facility and two other plants, as well as facilities in Texas.

Greg Bowser, spokesman for the Louisiana Chemical Association, said EPA has been assertive in modifying the rules for flares to ensure refineries and chemical plants install new equipment to analyze and monitor flares. He said facilities are often adding natural gas to the flares to keep them hot enough.

Email David J. Mitchell at dmitchell@theadvocate.com

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