ENVIRONMENTAL NEWS "Dead zone" in Gulf of Mexico draws federal—state attention
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state-federal task force led by EPA has been created to deal with a massive, persistent "dead zone" in the Gulf of Mexico. The lifeless, oxygenstarved zone that extends to waters as deep as 60 feet is apparently being choked by phosphates and nitrates flowing down the Mississippi and Atchafalaya rivers from farm states upstream. Although the zone was first detected more than a decade ago, it has worsened considerably since the Mississippi River floods of 1993 carried thousands of tons of nutrient-laden soil into the gulf. This summer, scientists, who refer to it as a region of hypoxia, estimated the zone to be 6120 square miles— twice what it was in 1987. Nancy Rabalais, a scientist at the Louisiana Universities Marine Consortium in Chauvin, said the nutrient-rich, sediment-bearing, fresh water flows into the saltwater gulf then, with the aid of prevailing winds, hugs the southern Louisiana and Texas coastiine. Rabalais, considered one of the leading experts on gulf hypoxia, said the nutrients promote rapid growth of phytoplankton. The phytoplankton cells sink to the bottom and are consumed by zooplankton. When
Gulf of Mexico "dead zone"
zooplankton fecal pellets sink to the bottom, the bacterial decomposition depletes oxygen in the lower water column. Consequently, bottom-dwelling benthos cannot survive in the oxygen-poor environment; species of fish and shrimp "basically get up and leave" the area, said Rabalais. Thus far, the hypoxic zone—which, at its peak covers about 1% of the gulf—has not had a serious effect on commercial fishing. But, said Rabalais, "at some point, there definitely could be a problem." Similar reports of hypoxia have been found elsewhere, including the Chesapeake Bay, although none has been on the scale of the zone in the gulf. Research this year showed that the zone formed later than normal, probably as a result of stormy spring weather. "Hurricanes and tropical storms usually do a good job of mixing up the water column and injecting oxygen into the bottom waters," said Rabalais, who has been measuring the hypoxic zone since 1985. Despite the harsh spring weather and the presence of Hurricane Danny in mid-July, Rabalais and other scientists have confirmed the formation of the zone again
Comparative size of the hypoxia (dead) zone Size Year
1990 1991 1992 1993 1994 1995 1996 1997
(square miles)
3576 4603 4172 6796 6410 7028 6924 6120
Source: Louisiana Universities Marine Consortium.
this summer, although it is slightly smaller than in 1996. "Scientific data reflect that the majority of the nutrient loading is coming from the agricultural community," said Cynthia Sarthou of the Gulf Restoration Network, a New Orleans-based environmental group that is pressing for remedial steps. Several groups are concerned by the prospect of an ecological and economic disaster. Using Section 319 of the Clean Water Act as their legal basis, the Earthjustice Legal Defense Fund (formerly the Sierra Club Legal Defense Fund) and the Gulf Restoration Network petitioned EPA in 1995 to convene a management conference—the first step in a regulatory process that would eventually lead to a "longterm, enforceable strategy" to cut nutrient loadings from agriculture, municipalities, and industry. "If we continue to kill it off every year, will we at some point have a permanent dead zone? We just don't know. But what we do know is, it is time for action," said Sarthou. EPA has declined to convene a management conference, preferring instead "to address the issue through voluntary actions," said Mary Belefski of EPA's watershed branch. One of those actions was to create a task force in July that includes the National Oceanic
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and Atmospheric Administration, the U.S. Department of Agriculture, and other federal agencies, along with 26 states in the Mississippi River basin. The first meetings were held in August. Although the task force will certainly embark on new research, it plans to address the problem initially through a series of educational programs and public meetings in key farm states. These programs would encourage soil conservation, better nutrient management, and reduced pesticide use. Existing U.S. Department of Agriculture con-
servation programs encourage farmers to reduce runoff by using soil-saving techniques, including no-till farming. Iowa has significantly reduced fertilizer use by imposing a statewide tax on its use. Sixty-five percent of the nation's cropland drains into the Mississippi River basin. Despite the voluntary nature of the gulf program, several informational meetings in the Midwest this summer have sparked anger from farmers who are concerned that new regulatory programs might increase costs and decrease yields. "There has been
Environmental justice assessments get boost under EPA draft guidance An EPA work group is developing technical guidance to bolster the credibility and use of environmental justice assessments. EPA has no rules requiring that socioeconomic factors be included in regulatory actions, explained Marty Halper, a scientist in the Office of Environmental Justice who is leading the effort. However, President Clinton's 1994 Executive Order on Environmental Justice recommends that environmental justice issues be considered in all government actions. A few EPA offices have acted on this order. Permitting guidance developed for state regulators details how to conduct an environmental justice assessment for hazardous waste site permits, Halper said, and a few regional offices are doing environmental justice assessments to determine whether any areas have been overlooked by their enforcement staff. Academic researchers have given increasing attention to environmental justice assessments as well. "For various reasons, people are attempting to find and define what an environmental justice community might be," Halper said. However, no standardized methodologies or definitions exist for the necessary socioeconomic factors, including racial data and household income, said Alfred Levine of the Center for Environmental Sciences at the College of Staten Island, City University of New York.
This makes it very difficult to do a credible environmental justice assessment. "Right now, I don't know what to do," he said. "If I did include some of these factors, someone would criticize it." Working as volunteers, EPA statisticians, experts in geographic information system modeling, and others are drafting the guidance as a tool for individuals assessing environmental impacts
"For various reasons, people are attempting to define what an environmental justice community might be." —Marty Halper, EPA's Office of Environmental Justice on low-income minority communities. Once published, the guidance should encourage people to do these assessments. "With the guidance, we are trying to alleviate some of the confusion and apprehension" associated with these studies, an EPA staffer said. A primary goal is to help an assessor think dirough questions relating to environmental justice issues, so that the methodology chosen and data selected match the assessment's objectives. If the assessment is expected to be challenged in court, die data quality should be extremely high, Halper
some hostility, but I think we are working through it," said Belefski. Rick Robinson, director of local and environmental affairs at the Iowa Farm Bureau, said, "It is entirely appropriate to talk about improving nitrogen management. But the reaction from many farmers is, 'What do you want us to do that we aren't doing already?'" Nevertheless, Midwestern farm bureaus have been holding a series of informational meetings, and a farmers' delegation will visit the gulf this fall for a firsthand look at the hypoxia problem. —RAE TYSON
said. "But if you are conducting the assessment to identify groups to receive a $10,000 environmental justice grant, don't do a $40,000 assessment," Halper said. The guidance will discuss available databases and their limitations. For example, it is difficult to address cumulative exposure: Site location is usually recorded as longitudinal and latitudinal data and does not describe a manufacturing plant's distance from a housing community or another plant. The guidance will include definitions of minority, community, and low income. However, it is only a tool; the analyst will revise those definitions to reflect the actual community. For example, an assessor will define a low-income minority community in Montana differently from one in Alabama. The guidance does not address policy interpretation. "It just says these are the technical difficulties you will face, and here are the ways of potentially dealing with them," said Halper. Still, some business groups are concerned that the definitions might later be incorporated into a regulation, said Mary Barnhard, manager of environmental policy of the U.S. Chamber of Commerce. If that is the case, businesses would like to weigh in. Once it becomes available for peer review next year, EPA officials expect the guidance to stir up debate. "The guidance is going to be controversial, because it could prove some areas should not be considered environmental justice regions, and a lot of other areas are," said an EPA staffer. —CATHERINE M. COONEY
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