Mayor Marion Barry yesterday appointed Peter S. Ridley, former D.C. Recorder of Deeds, as acting chairman of the Alcoholic Beverage Control Board pending the outcome of a U.S. criminal investigation into allegations of misconduct by the board's two top officials.

Ridley's appointment to take over chairmanship of the ABC board from Robert C. Lewis is effective immediately, Barry said. Lewis, who also serves as head of the city's department of Licences, Investigations and Inspections, and James E. Boardley, staff director of the ABC board, were placed on involuntary administrative leave last week after federal investigators informed Barry that the two men were the subject of a grand jury probe.

Sources close to the investigation have said that it centers on allegations that the two officials attempted to secure an interest in operations of the new Hechinger Mall at H Street and Bladensburg Roadk NE in exchange for favorable licensing consideration.

Lewis had declined comment other than to issue a blanket denial of wrongdoing. Efforts to reach Boardley for comment have failed.

Ridley retired from the city government last year after serving as Recorder of Deeds for the past 19 years.

Dwight S. Cropp, Barry's executive secretary and also a member of the ABC board, said Ridley was chosen because of his familiarity with the District of Columbia government, his experience with the kind of administrative law hearings the board conducts and his credibility in the city.