One day after the Reagan administration announced "major accomplishments" in cleaning up the nation's hazardous waste dumps, environmentalists and a House subcommittee charged yesterday that the administration is weakening the program by refusing to spend cleanup funds on many dumps that pose health hazards.

The critics released internal Environmental Protection Agency documents showing that the agency refused to spend emergency funds in a neighborhood in Fort Smith, Ark., where the Public Health Service warned that toxic chemicals pose "a significant threat to public health."

And Rep. James J. Florio (D-N.J.) charged that internal EPA budget documents show the agency has drawn only $88 million from the superfund, the toxic waste cleanup program, leaving a surplus of $364 million.

EPA officials called the criticism unjustified and political, timed to tarnish the administration's image just before next Tuesday's election.

At the Arkansas site, federal officials found toxic polychlorinated biphenyl (PCB) in high concentrations along a dirt road, and federal officials warned that children could accidentally swallow the contaminated dirt. PCBs have been linked to liver, skin and blood disease.

Earlier this month, the EPA turned down a request for federal aid to Arkansas in a letter explaining in technical terms that the public health risk was not high enough under EPA standards.

"In order for a child to consume an acute lethal dose of PCBs, the child would have to eat about 150 grams of oil-laden dirt, the equivalent of about three large candy bars," wrote Rita M. Lavelle, head of EPA's hazardous waste program.

Lavelle's explanation, which EPA officials now acknowledge as "an unfortunate choice of words," was denounced yesterday by the Environmental Defense Fund, a nonprofit group that made the Arkansas documents public.

"EPA's standard for taking emergency action -- dead bodies -- is repugnant to any notion of protection of human health," said the fund's toxicologist, Ellen Silbergeld.