Dow Chemical and two of its subsidiaries would pay a $3 million fine and spend $294 on new pollution controls in a proposed settlement of regulators' claims that their plants in Plaquemine, Hahnville and Texas allowed too much pollution into the air.

The U.S. Environmental Protection Agency and the state Department of Environmental Quality have alleged a series of Clean Air Act violations in a new civil complaint. They say Dow and the two subsidiaries, one of which is Union Carbide, operated 26 flares in Louisiana and Texas in a way that made them less efficient at destroying harmful chemical air pollution for more than a decade.

Flares burn off harmful gases, which causes the telltale flames visible at plants.

In the joint complaint, the regulators allege these operational failures had "resulted in thousands of tons of illegal emissions of volatile organic compounds," hazardous air pollutants and other pollutants into the air.

Under a pending settlement with the regulators, Dow Chemical and its subsidiaries would pay $3 million in civil penalties and agree to fence-line air monitoring for benzene, a human carcinogen, with results available to the public online, among other requirements.

In Louisiana, the proposed settlement would affect the operation of six flares at Dow's Plaquemine complex in Iberville Parish outside Baton Rouge and eight flares at Union Carbide's plant in Hahnville in St. Charles Parish outside New Orleans. 

The other affected flares are at a Dow plant in Freeport, Texas, and the Sabine River Works in Orange, Texas.

“This settlement means cleaner air for communities across Texas and Louisiana and reinforces EPA’s commitment to enforce the law and hold those who violate it accountable,” Susan Bodine, assistant administrator for EPA’s Office of Enforcement and Compliance Assurance, said in a statement.

Ashley Mendoza, a Dow spokeswoman, said the company has been working since 2013 with EPA "to ensure it meets new combustion efficiency expectations" and began making flare improvements two years later. She added the company expects to have them finished by 2025.

Dr. Chuck Carr Brown, secretary of DEQ, said his agency will continue to work with EPA and the Department of Justice to reach settlements that solve compliance matters. 

“The Clean Air Act provides a blueprint for industry to operate in a safe and controlled fashion,” Brown said in the statement.

Under the settlement, DEQ would get $675,000 of the penalties and EPA would get the rest. Dow and its subsidiaries would also agree to pay for another $424,786 for beneficial environmental projects in Louisiana.

Those projects would pay for several years of environmental education programs and buy DEQ a new handheld monitor for hydrogen sulfide, a toxic gas, and an aerial drone that can do air monitoring, the proposed settlement says.

The EPA and the Department of Justice estimated that the new pollution controls will reduce harmful volatile organic compounds by 5,689 tons per year; toxic air pollutants, including the benzene, by 480 tons per year; ozone-forming nitrogen oxides by 127 tons per year; and minute particulate matter by an unspecified amount. 

VOCs and nitrogen oxides help form harmful smog and ground-level ozone that can lead to long-term respiratory damage. Particulates can get in deep in the lungs and also cause severe respiratory damage.

The changes would also cut hundreds of thousands of tons per year of greenhouse gases known to worsen global climate change and sea level rise.

EPA and DEQ filed the civil complaint over the alleged violations and the proposed consent decree on Jan. 19 in U.S. District Court in New Orleans. The settlement remains in a 30-day public comment period and needs final court approval, Department of Justice officials said. 

The operation of industrial flares, which have an important role in ensuring dangerous emissions are reduced, has come under increasing attention from EPA and others. In recent years, the agency has tightened the rules on their operation for oil refineries and ethylene crackers.

But, last fall, the EPA came under fire from environmental groups, who alleged in a lawsuit in Washington, D.C., that the agency needed to update its rules for flare operations in many other kinds of industrial facilities because the flares were being run less efficiently and that failures were leading to higher-than-expected air pollution.

Late last year, the American Petroleum Institute, an oil and gas industry trade group, also announced an initiative among more than 80 company members to cut flaring and improve flare efficiency.

Each of the four chemical complexes affected by the settlement include olefin plants that make ethylene and propylene, feedstocks in the production of consumer plastics, carpet and car parts, and polymer plants that make polyethylene, a feedstock that shows up in food containers and truck bed liners.

Industrial flares that so often frame the horizon behind Louisiana chemical facilities are among their most important pollution control devices, serving as the eraser of last resort that burns up emissions routed to them from various sections of a plant.

The flares are purported to have 98% or 99% destruction efficiency. That assumption is built into state air pollution permits for large industrial facilities that are supposed to ensure plants operate in a way that is protective of public health and the environment.

But the EPA complaint alleges that Dow and its subsidiaries made modifications to their flares and their flaring practices without proper permitting or monitoring equipment and failed to run those flares so they had the most complete destruction of the chemicals shunted to the burning flame.

The flares in question are "steam assisted," which means they used steam as a way to prevent sooty black smoke. But the use of too much steam, which Dow and its subsidiaries are accused of doing, can cut down on flame temperature and reduce combustion levels of harmful chemicals.

Part of the settlement would require Dow and the subsidiaries, Union Carbide and Performance Materials NA Inc., to install monitoring equipment that allows the chemical companies to better check those flares' operating conditions, the Department of Justice says.

The companies would also have to install systems that recycle the gases for fuel or for sale that would otherwise have been sent to and burned up in the flare.

Dow also must create plans to minimize wastes to cut flaring further, the Department of Justice says.

PMNA operates the Orange, Texas, plant.


Email David J. Mitchell at dmitchell@theadvocate.com

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