Decades of Delay

When a petrochemical firm dumped 200 tons of mercury into Japan's Minimata Bay during the 1950s, fish floated to the surface, waterfowl dropped from the sky and cats that had eaten fish from the bay went crazy. Several hundred people died and more than 10,000 were made ill, many of them for life.

This well publicized environmental disaster, though, did nothing to deter Alcoa from dumping mercury into Lavaca Bay from 1966 to 1970. While Alcoa's contamination of Lavaca wasn't nearly as serious as what happened at Minimata, it does raise serious questions about the long-term safety of the bay.

The mercury in Lavaca Bay came from Alcoa's chlor-alkali plant. According to state records, wastewater containing as much as 67 pounds of mercury a day was discharged directly into the bay. In August 1970 the Texas Water Commission issued an emergency order to halt that discharge, and for the next nine years the wastewater was diverted to a dredge disposal island, where it was mixed with gypsum to remove the mercury. The mercury was then stored at an onshore disposal lake on the Alcoa plant property.

In 1979 Alcoa closed its chlor-alkali plant; 14 years later, in August 1993, the Texas Natural Resource Trustees recommended that the Alcoa plant, the spoil island and the mercury-contaminated areas of Lavaca Bay be placed on the National Priorities List -- i.e. become a Superfund site.

The trustees found that although the chlor-alkali plant had been shut down for over a decade, mercury was continuing to be released from both it and its spoil island as a result of wind transport and storm-water runoff. In several studies, samples of the tissues of crabs and fish from near the source of greatest contamination showed levels of mercury well above those regarded as safe.

Alcoa officials at first fought the Superfund designation. That response is understandable. Texas agencies have been inclined to cut polluters a lot of slack. Superfund sites fall under stricter federal scrutiny. If Alcoa doesn't clean up the site to EPA standards, the EPA can hire a contractor to do the job and send Alcoa the bill.

Alcoa is already having problems. Ordered to study the feasibility of allowing no surface-water discharge from its 2,000-acre Point Comfort site, Alcoa figured it would have to buy 12,600 acres of land on which to build detention basins. It would have to build 14 pump stations and add 28 miles of pipeline. Construction costs could range from $167 to $300 million; operating costs could be nearly $6 million a year.

How effectively this would deal with mercury contamination of Lavaca Bay is debatable. As Alcoa environmental officer Ron Weddell points out, the total amount of mercury in Alcoa's storm-water runoff has been estimated at less than 50 pounds a year. Meanwhile, nearby Formosa Plastic has been given permission by the state to discharge 58.6 pounds of mercury a year.

Still, stopping runoff is the least of Alcoa's problems. The real issue is what to do with the contaminated sediment that covers 2,000 acres of land at the bottom of Lavaca Bay. Nobody has ever cleaned up an underwater site like this before. One proposal is to dredge up the sediment, move it to land and then treat it. Another approach would be to cap the sediment with a clay compound. Neither treatment is cheap; estimated costs begin at a quarter of a billion dollars.

And no one is sure either solution will actually work. Dredging could simply stir the mercury up; a cap might leak. So some have proposed doing what has already been done for the last 25 years: nothing. Simply let the mercury gradually trickle out and be diluted by natural forces.

Whether that would actually work, or whether it's just a way to continue ignoring the problem, is something the Superfund designation might help clear up. One benefit of being on the Superfund list is that Lavaca Bay is going to be studied more intensively than ever before. The hair of people who live in the area will be sampled for mercury residue. Homes at Point Comfort are going to be inspected as well.

-- Michael Berryhill