The Environmental Protection Agency is misleading the public when it says it has cleaned up six of the nation's worst toxic-waste dumps under the federal "Superfund" law, according to a national citizens' group that has reviewed the agency's records.

The National Campaign Against Toxic Hazards said that cleanups of three sites were inadequate, that two posed "only minor hazards" and probably should not have been on the Superfund priority list and that a sixth was cleaned up under the Clean Water Act, not under the Superfund law. In one case, the material from one site was moved to another nearby site.

The group said thousands of tons of contaminated soil from a Velsicol Co. site on the Pine River in Michigan were trucked across the river to a second Velsicol site -- which also is on the Superfund priority list.

The first site, a 3.5-acre plot once used as a golf course, was declared clean in July 1982. But the cleanup essentially concentrated the toxic waste at the second site, a 50-acre plot that Velsicol promised to clean up in a $38.5 million agreement with the EPA four months later.

The report adds a new dimension to the Superfund debate, which for three years has centered on whether the agency is moving quickly enough to clean up the nation's leaking toxic-waste sites.

Although nearly 800 of an estimated 14,000 potentially dangerous sites have been singled out for quick action as "imminent hazards" to public health, the EPA has finished work on six.

The figure has become standard Democratic campaign fodder in the 1984 presidential campaign, despite complaints from EPA officials that it unfairly ignores less-complete action on hundreds of other toxic dumps.

The citizens' group suggests, however, that "cleanup" is being misapplied in some cases. The National Campaign is an umbrella organization, established this year to coordinate the work of several national and dozens of local community groups on toxic-waste issues.

While the report gives the EPA credit for taking quick and effective emergency action on most of the six sites, it is less charitable about the finished product.

"There is substantial evidence that EPA has left in place toxic chemicals that could still threaten the communities surrounding the sites," the report said.

The report cited the Chemical Metals Industry site in Baltimore, once stacked high with leaking drums of liquid chemical waste. The site became a national landmark of sorts in December 1981, when workmen, under the glare of television cameras and the beaming faces of local and federal environmental officials, put the finishing touches on a clay shield.

The Baltimore site, two plots separated by 20 rowhouses, was the first toxic-waste site to be declared "clean" under Superfund.

The cleanup consisted of removing the drums, scraping the ground to a depth of one foot or less and adding a clay cap to prevent rainwater from flushing more contaminants out of the ground.

But the report said the EPA had found high levels of solvents to a depth of 15 feet, potentially contaminating ground water that flows toward a nearby creek. The report said vapors from the solvents could enter the basements of the rowhouses through ground water seepage.

Similarly, the report took exception to the cleanup of the Butler Tunnel in Pittston, Pa., where tens of thousands of gallons of hazardous waste poured from an abandoned mine tunnel into the Susquehanna River in July 1979.

The government did "a very thorough job" in responding to the emergency, the report said, although it took that action under a provision of the Clean Water Act rather than under Superfund. But the tunnel still discharges contaminated water from time to time, suggesting that a pool of toxic waste is lurking inside the mine.

Because abandoned mine shafts often are connected to the surface by hundreds of "boreholes," which still are in common use as sewage drains, the chemical pool still could pose a threat to human health, the report said.

The report found fewer problems with the Luminous Processes Inc. site in Athens, Ga., where workers once produced luminescent watch and clock dials with radioactive paint. In most respects, the cleanup was "done thoroughly and quickly," it said.

But it added that "ground water contamination and investigation of deeper soil layers was not done and consequently it is possible that radium contamination remains trapped in deeper layers . . . . These possibilities all need to be ruled out."

The report contended, and EPA officials agreed, that two other sites on the Superfund cleanup list posed little immediate danger to the public and were easy to clean.

One of them, the Walcott Chemical Co. in Greenville, Miss., entailed 226 drums of mineral spirits and acids stored in a deteriorating warehouse. The site scored 8.2 on the EPA's hazard-ranking system. Generally, Superfund money is limited to sites with scores of 28.5 or higher.

The EPA agreed that the drums posed a fire hazard, however, and the warehouse owner quickly agreed to dispose of them.

The sixth site, Chemical Minerals Recovery in Cleveland, was cleaned up nearly as quickly. The EPA put the site on the priority list in October 1981, and within a month asked for money to remove 1,400 drums of waste inside and outside of a dilapidated warehouse. By the following May, the work was done.