The Navy's Project ELF -- a controversial communications system designed to send signals to deeply submerged nuclear submarines -- has been judged to pose no danger to the public health or the environment, according to a new report by a Navy-financed independent research group.

The $240 million project has been attacked by environmentalists who are concerned that the extremely low frequency (ELF) radio waves generated by the system could harm residents living nearby. In January 1984, a federal judge issued an injunction against construction of the project in Wisconsin and in Michigan's Upper Peninsula. The injunction was part of a lawsuit brought by Marquette County, Michigan, and the state of Wisconsin, and was later lifted by the U.S. Court of Appeals. The Navy has since resumed construction of the project.

In a recent report at a special briefing on Capitol Hill, the American Institute of Biological Sciences (AIBS) in Arlington concluded: "It is unlikely that exposure of living systems to ELF electric and magnetic fields in the range of those associated with the Navy's ELF Communications System can lead to adverse public health effects or to adverse effects on plants and animals."

"Practically speaking, I don't think that there's any problem from Project ELF ," AIBS committee chairman E.B. Graves, a professor of biology and poultry science at Pennsylvania State University, told congressional staffers at a recent briefing. "But I don't mean to imply that further research should not be done, or that there aren't any effects, because there are. Effects, if they exist, are so subtle that you'll never pick them up."

Both the report and the AIBS committee that wrote it came under sharp attack from critics.

"Scientific evidence clearly shows the potential risk and the potential health hazard of Project ELF -- the magnitude of which is unknown," said Andrew Marino, a biophysicist from Louisiana State University Medical Center, who served as a consultant to the committee. "Clearly I think that they are wrong on the facts and utterly unqualified to make such a judgment."

Among the biological effects that have been associated with ELF waves are changes in the way calcium enters and leaves brain cells, the perception of flickering lights known as magnetophosphenes within the visual field and certain behavioral changes. Some research suggests an increased suicide rate associated with exposure to ELF radio waves.

While the AIBS authors reviewed these and other scientific studies prior to reaching their findings, they reported that "firm conclusions concerning effects at the cellular tissue levels are difficult to draw from the literature review of studies of ELF magnetic field effects on cellular tissue and animal systems."

The report noted, however, that "there is a growing body of evidence that several aspects of the biochemistry and physiology of cells and organized tissues may be perturbed by exposure to ELF magnetic fields that induce electric currents in tissues and extracellular fluids that exceed normal physiological levels."

Finally, the AIBS committee concluded that "because of certain ambiguities in the scientific literature, the Navy should continue to monitor the literature and respond appropriately to any significant new information."

But critics are not convinced. "Opinions were established before the committee met," Marino said. "There was a hidden agenda."

"The authors of the report and the Navy are simply too ready to dismiss what I think are significant research results because of perceived deficiencies in scientific methodology or because they don't believe that the results are relevant to this project," added Shari Eggleson, a Wisconsin assistant attorney general.

Project ELF, now being built on a 56-mile tract in Michigan's Upper Peninsula and at another site in Wisconsin, is considered important by the military because submarines cannot receive standard radio signals when deeply submerged.

A test of the 28-mile Wisconsin portion of Project ELF, located near Clam Lake, "was successfully completed March 15," reported Capt. Ronald Koontz, Project ELF program manager for the Navy. General Telephone and Electric (GTE) shipped the first of five receivers to the Navy late last month. Further tests of the system are scheduled for July through December.