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Mercury Purge

Congress is moving legislation to outlaw mercury-cell chlorine plants

by Cheryl Hogue
June 15, 2009 | A version of this story appeared in Volume 87, Issue 24

Credit: Oceana
This Olin chlor-alkali plant in Georgia is one of four mercury-cell facilities whose production methods could become illegal.
Credit: Oceana
This Olin chlor-alkali plant in Georgia is one of four mercury-cell facilities whose production methods could become illegal.

The chemical industry has produced chlorine, sodium hydroxide, and potassium hydroxide from salt solutions for more than a century. Companies employ a variety of production methods to make these materials. In the late 1800s, businesses began producing the chemicals in giant cells containing elemental mercury, which serves as the cathode in the electrolysis of brine. A second production method, which uses a mercury-free diaphragm cell, was adopted in the early 1900s. The newest manufacturing technology, introduced more than three decades ago, relies on ion-exchange membranes. Today, the U.S. chlorine industry employs all three processes.

Now, Congress is working on legislation to make the oldest and dirtiest of those production methods illegal. The bill, H.R. 2190, would outlaw the use of mercury in chlorine production, beginning two years after the measure is enacted.

The bill is already moving. It passed its first legislative hurdle on June 3, garnering approval from the House Energy & Commerce Subcommittee on Commerce, Trade & Consumer Protection.

H.R. 2190's goal is to cut mercury pollution. When the elemental form of the neurotoxic metal ends up in waterways, it is converted by bacteria into methylmercury, which builds up in fish that people eat. Pregnant women who eat those fish can pass mercury to their developing fetuses, where the metal can damage the brain and nervous system. Preschool children who eat mercury-contaminated fish are also at risk.

Sponsors of H.R. 2190, which is backed by environmental activists, say it's time for polluting mercury-cell plants to go.

But some legislators and at least one chemical manufacturer that operates a mercury-cell plant are urging Congress not to move so fast. They argue that the bill is likely to trigger the shutdown of four facilities, which would cause the loss of what could be hundreds of jobs without significantly reducing U.S. mercury pollution.

The measure squarely targets four mercury-cell-based chorine production plants: an Ashta plant in Ashtabula, Ohio; Olin's factories in Charleston, Tenn., and Augusta, Ga.; and a PPG Industries' facility in Natrium, W.Va.

Two other mercury-cell chlorine-production facilities currently exist in the U.S., but H.R. 2190 may not significantly affect them. One, Olin's factory in Saint Gabriel, La., which it bought from Pioneer, was shut down several months ago. Olin is replacing it with a new facility that will use membrane technology. Meanwhile, the Erco Worldwide plant in Port Edwards, Wis., is currently undergoing conversion to the ion-exchange process (C&EN, Aug. 20, 2007, page 25).

Mercury-cell plants released much larger amounts of quicksilver in past decades than they do today, says Arthur E. Dungan, president of the Chlorine Institute, an industry trade group. Under an Environmental Protection Agency effort begun in 1996, mercury-cell plants voluntarily cut emission of the metal more than 90%, he tells C&EN.

Credit: Pioneer
H.R. 2190 would prohibit the use of mercury cells, like the one shown, to make chlorine in the U.S.
Credit: Pioneer
H.R. 2190 would prohibit the use of mercury cells, like the one shown, to make chlorine in the U.S.

"The numbers might be down, but they still release hundreds of pounds a year," counters Jacqueline Savitz, senior campaign director for Oceana, an environmental group.

According to Toxics Release Inventory data for 2007, the most recent year for which this government-required information is available, the four mercury-cell plants together released or disposed of 2,850 lb of mercury. Ashta, with 202 lb, had the least, followed by Olin's facility in Georgia with 206 lb, and Olin's Tennessee plant with 834 lb. PPG released the most—1,608 lb.

A recent report from Oceana says mercury pollution from mercury-cell facilities has cost the U.S. economy millions of dollars in lost wages annually. The loss is because of lowered IQs of people exposed to this neurotoxic metal, according to the report.

Rep. Jan D. Schakowsky (D-Ill.), who introduced H.R. 2190 earlier this year, says the four remaining mercury-cell factories are an "unnecessary source" of mercury pollution. Alternative technology is already on-line for chlor-alkali production, unlike with coal-fired power plants, which are a major source of mercury. Electricity-generating plants that burn coal release some 48 tons of the metal per year, according to EPA.

But others in the House are against the bill because of economic concerns. Rep. George P. Radanovich (R-Calif.), the top Republican on the subcommittee, opposes the bill because it "congressionally mandates the closure of four plants."

Although the Chlorine Institute has not yet taken a stance on whether to support or oppose H.R. 2190, Dungan agrees with Radanovich's conclusion that the bill, rather than leading to conversion to membrane technology, would force the closure of the four mercury-cell facilities. A main reason for this, Dungan tells C&EN, is the bill's two-year deadline for the plants to abandon the mercury-cell process. Switching a plant to newer technology involves a raft of time-consuming details, from obtaining state and local permits to arranging for financing. This usually takes more than two years, he adds.

When the Commerce, Trade & Consumer Protection Subcommittee approved H.R. 2190 earlier this month, Republicans failed at an attempt to change the deadline for conversion of mercury-cell plants to 2020. That is the year that the European Union, which has many mercury-cell facilities, will ban its use of this technology.

Without specifying dates, Schakowsky, the bill's main sponsor, says she would consider pushing back the deadline as the measure continues through the legislative process.

The deadline in the bill wouldn't be the only factor in companies' decisions on whether to retool or shut down mercury-cell plants. The state of the economy also will have a say on how quickly any of these actions might be carried out, Dungan says. As one of the effects of the current downturn, the U.S. chlor-alkali industry has been running at 70% of capacity, on average, he says. If demand remains low, companies could find it more financially sound simply to shutter the mercury-cell factories rather than install new technologies. This would leave membrane and diaphragm plants to meet market demand.

Ashta is facing these economic realities. At a May hearing on the bill held by the subcommittee, Richard Jackson, executive vice president of operations at Ashta, said passage of H.R. 2190 would "take us out of business." He said the $60 million the company estimates it would cost for the conversion doesn't make good business sense.

"Ashta has repeatedly evaluated the financial impact of converting our plant to membrane-cell technology. In each case, we have concluded that the economic risk to the company was not warranted," he testified.

In the face of the economic downturn, especially in hard-hit Ohio, requiring Ashta to adopt membrane technology "is unwarranted, it is confiscatory, and it is bad public policy," Jackson contended. And, noting that the company meets or goes beyond current environmental regulations for mercury, he added, "Closing Ashta's facility will have no measurable effect on global or local mercury emissions."

In contrast, Catherine A. O'Neill, an associate professor at Seattle University School of Law, told the subcommittee that mercury-cell plants that have switched to newer technologies are likely to remain competitive for years to come.

Oceana's Savitz says membrane technology is about 30% more energy efficient than mercury cells. "The cost of modernizing these plants can typically be recouped in about five years, and it will help the plants become more competitive, thus protecting jobs and local economies," she says.

Aside from the proposed ban on mercury-cell chlorine production, the Chlorine Institute is questioning a provision in H.R. 2190 that would affect the disposition of mercury recovered from closed or converted chemical plants. The bill would ban the export of mercury from chlor-alkali facilities starting on the day the legislation becomes law. In contrast, a law passed by Congress last year bans U.S. mercury exports in 2013.

The U.S. supply of mercury, recovered from old thermometers, fluorescent lamps, shuttered mercury-cell plants, and gold-mining operations, surpasses demand. Thus, this country's excess mercury generally ends up being sold to a broker and placed on the world market.

The export ban is designed to depress global supplies of commodity mercury that are widely used in small gold-mining operations in developing countries. There, miners exploit a cheap or even free source of mercury to amalgamate flecks of gold, and the quicksilver ends up poisoning the miners, their communities, and nearby waterways (C&EN, May 28, 2007, page 26).

The export ban enacted last year requires the Department of Energy to accept and store excess commodity mercury, including that from decommissioned mercury cells, starting in 2013.

Dungan questions why the chemical industry's mercury should get a different export deadline than mercury recovered from old equipment such as mechanical switches and thermometers or from mining wastes.

The two companies that are in the process of converting or replacing mercury-cell facilities could find themselves caught by this deadline. Erco plans to sell the mercury from its Wisconsin plant, company President Paul Timmons tells C&EN. Under current hazardous waste regulations, a company can store recovered mercury on-site for only 90 days, so Erco is taking steps to comply with the law by selling the metal, he says.

H.R. 2190, as adopted by the subcommittee, would change that 90-day deadline. It would allow chlor-alkali plants to store recovered mercury until DOE begins accepting the metal for storage in 2013.

Members of Congress haven't publicly discussed the bill's earlier export deadline for chlor-alkali plants than for mercury from other sources. But as H.R. 2190 continues to move, their views on this and the rest of the bill may become clearer.

The bill remains a "work in progress," according to Rep. Bobby L. Rush (D-Ill.), chairman of the Commerce, Trade & Consumer Protection Subcommittee. He says to "expect changes" as the full Energy & Commerce Committee takes up the bill, which is likely in the coming weeks.


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