In a finding that angered environmental groups, the EPA has determined that no additional specific actions are warranted at this time to protect the nation's water bodies, including the Chesapeake Bay, from air pollution.

The agency, after completing a report to Congress about the impacts of airborne deposition on the "Great Waters" of the United States, concluded that "no further emissions standards or control measures" were needed beyond those already being implemented.

"We have not concluded that we need additional regulations beyond those that are in the Clean Air Act but we continue to study this issue," said Nancy Sutley, an EPA clean air policy adviser. "We believe those standards that are in effect will help a great deal. We need to do some more research and understand better the problem."

The EPA took comments on its conclusion during the summer and is expected to make a final decision in March 1998.

But its preliminary conclusion was strongly criticized by environmental groups that argued its own report shows that airborne nitrogen is a major contributor to the Chesapeake's water quality problems while air pollution is one of the leading contributors of toxics to the Great Lakes.

"We think they're all wet," said Mike Hirshfield, vice president for resource protection with the Chesapeake Bay Foundation. "If the EPA rules in a way that we think is wrong, we'll have to look at all our options, up to and including additional litigation."

In comments filed with the EPA, the foundation contended that the agency used a narrow, and possibly "illegal" reading of the Clean Air Act to reach its conclusion.

The National Wildlife Federation, meanwhile, accused the agency of taking a "wait and see" approach to protecting water bodies which would result in their continued degradation by airborne toxics.

"The EPA has made a decision that will mean that toxic air pollution continues to contaminate our nation's Great Waters," said Wayne Schmidt, director of the NWF's Great Lakes Natural Resource Center.

Both groups, along with the Sierra Club, had earlier sued the EPA for its failure to complete an assessment about the impact of air pollution on major water bodies, which by law was to have been completed nearly two years ago.

The controversy centers on the Great Waters portion of the 1990 Clean Water Act, which required the EPA to examine the effects of "hazardous air pollutants" on the Chesapeake Bay, the Great Lakes and Lake Champlain and to determine whether existing air pollution control efforts were adequate to protect those water bodies.

After a suit by the environmental organizations, the EPA in late June completed a report, "Deposition of Air Pollutants to the Great Waters." The 218-page report summarized previous studies indicating that airborne nitrogen contributes about a quarter of all the nitrogen and a large amount of the toxics that enter the Chesapeake Bay. The report also confirmed earlier studies showing that airborne pollution also contributes a large amount of toxics- including most of the mercury-to the Great Lakes and Lake Champlain.

Environmentalists do not disagree so much with the report, as they do with the EPA's conclusion that programs within Section 112 of the Clean Air Act-the program to control emissions of hazardous air pollutants-are adequate to deal with the problem.

They also quarrel with the agency's conclusion that controlling airborne nitrogen to protect the Bay is "beyond the scope" of the Great Waters program because nitrogen is not on list of nearly 200 hazardous air pollutants on the Section 112 list. As a result, the EPA decided not to deal with the nitrogen issue at this time, though it could be addressed in future Great Waters reports, which are required every two years.

The CBF said the EPA's position "strains credulity."

"If the EPA truly believes that it has no Clean Air Act obligation to act directly to prevent airborne nitrogen compounds from strangling the Chesapeake, it owes it to Congress, to the American people, and to future generations to report this remarkable conclusion to Congress immediately," the CBF stated.

The CBF called the conclusion "narrow" and "patently illegal." In its comments, the foundation stated that the Clean Air Act required the EPA to assess whether air pollution controls are adequate to "prevent serious health and serious or widespread environmental effects" and that the agency was to establish "further emission standards or control measures as may be necessary and appropriate to prevent such effects."

In other words, the CBF stated, the agency was directed to "solve a practical, real-world problem" and was not limited to dealing with the list of chemicals in Section 112.

It also cited several examples of Clean Air Act wording which it said allows the EPA to examine any air pollutant affecting water quality, not just those on the Section 112 list.

The EPA stated that other areas of the Clear Air Act were addressing the nitrogen issue, but CBF said the agency failed to determine whether those programs adequately protect the Bay.

"The issue is not whether other programs are effective or helpful, but whether they are sufficient, without more, to protect the Great Waters," the CBF stated. "The EPA makes no attempt to answer this statutory question."