The National Endowments for the Arts and the Humanities are being investigated by the General Accounting Office for possible violations of the Freedom of Information Act and the Federal Advisory Committee Act.

An audit of the two agencies was requested by Rep. Richardson Preyer (D-N.C.), chairman of the House Subcommittee on Government Information and Individual Rights -- which is responsible for initiating audits of various government agencies -- in a letter to the GAO dated May 8. In his letter, Preyer said he had received "several specific complaints alleging violations of these statues." The complaints involved charges that the Endownments had kept information secret, failed to supply correct records about public requests for information and selectively excluded the public from closed proceedings.

"We think we're all in full compliance with both laws," said NEA chairman Livingston Biddle, who said his agency was cooperating fully with the investigation. Officials from both Ndownments said they have been audited before by GAO.

Among Preyer's charges were:

When the Humanities Endowment filed its routine annual Freedom of information Act report this year stating how many requests for information had been denied, the NEH noted no denials and no appeals. The subcommittee staff was surprised by this. "At that time, I had on my desk communication from two individuals who were denied requests for information," said one subcommittee staffer. "In both cases I had the letter from the Endownment denying the access."

When the subcommittee informed the NEH of this, the Endownment resubmitted a report. This time, the NEH listed five denials and one appeal. "We began to wonder," said one subcommittee staffer.

In addition, Preyer wrote in his letter to the GAO that "most of these denials were made by employes not authorized to do so."

The NEH also denied a public request for a 1977 consultant's report on its challenge grant program. The Endownment claimed it was an intra-agency document. But, wrote Preyer, the report contained "Copies of a public speech and a publication . . . No attempt had been made to make available portions of the report that clearly were subject to release."

The National Endowment for th Arts released a summary of minutes of a closed advisory panel meeting in which they listed people present at the meeting. Preyer wrote that the summary indicated the "meeting in question had been selectively closed . . . the Arts Endowment allowed certain individuals who were neither agency employes nor advisory panel members to remain in attendance, while excluding others." A subcommittee staffer said the people in question included a staff member from the NEH as well as two people from two broadcasting agencies.

Preyer also said that, in connection with closed meetings, the NEH closed "a higher precentage of meetings in 1979 than any other agency."

NEH chairman Joseph Duffey said he felt the audit was "entirely proper."

About the Freedom of Information Act questions, he said, "You're talking about an act which can be interpreted in differnt ways."

He also said that the consultant's report was withheld because the material in it was "given in confidence . . . The speech was just an appendix -- not part of the report."

Mary Ann Tighe, deputy Chairman of the NEA, said, "We're very careful about panel attendance. The only other people who could have attended would have been consultants who did on-sight visits to the applicant being discussed." About the NEH staffer, she said, "It would be very rare -- maybe if we were jointly funding something."

The GAO, which begain its investigation about two weeks ago, will eventually make recommendations, of necessary, about how the Endowments can better comply with the laws. Then both agencies will have to explain in writing to Congress their plans for compliance.

"We certainly don't have anything against the Endowments," said Preyer yesterday. "I've always considered myself one of their strongest supporters. But we find it easy for groups to drift back into old habits, and we have to remind them (of the laws) from time to time. I guess it's easier to operate with closed meetings."