A D.C. Department of Human Services contract document shows that the agency awarded a $24,990 contract to an FBI sting company without the required signatures of top agency authorities, DHS officials said yesterday after locating a document that had been missing for months.

Agency officials said that two contracting officials found the original contract document yesterday in a file where they had placed it in July. Federal authorities investigating alleged contracting improprieties have been searching for the document since May in an attempt to find out who approved the contract.

The document shows no signature by the agency's director, deputy director or any commissioner, according to a copy provided by agency officials. The lines for signatures of an agency budget official or the contract branch chief are also blank, officials said. No justification for the lack of competitive bidding is given.

A spokesman for Mayor Marion Barry said the document will be turned over to federal authorities. A grand jury subpoenaed the document in May but agency officials were able to provide only copies.

In interviews this week, FBI agents asked contracting officials whether the document was stolen from the agency's contract files after an FBI undercover operation was unveiled on May 22.

In another development in the contracting probe, Michael Davis, a former Human Services Department employe, testified yesterday for two hours before a federal grand jury investigating whether former DHS director David E. Rivers steered contracts to his friends.

Davis, who resigned in May as special assistant to Dr. Reed V. Tuckson, the agency's public health commissioner, is a friend of Rivers and D.C. businessman John B. Clyburn, another key figure in the contracting investigation. Michael Rosier, Davis' attorney, said after the grand jury session, "I don't feel my client is the target of the investigation and beyond that I don't want to comment."

Sources have said federal authorities are attempting to determine whether Davis acted as an intermediary in directing DHS contracts to specific firms. The authorities have suggested that Davis exercised improper influence within DHS as a result of his friendship with Rivers, sources said.

Gwendolyn A. Mitchell, who heads a marketing firm called Page One Communication Inc., also was subpoenaed yesterday to testify before a grand jury that is investigating whether convicted cocaine dealer Karen K. Johnson received payments from Clyburn and another contractor in exchange for her refusal to testify about alleged cocaine sales to Barry.

The subpoena notified Mitchell that she was a target of an investigation of alleged obstruction of justice and impeding a grand jury probe, sources said. Mitchell did not appear before the grand jury but was questioned privately by prosecutors.

Sources said Mitchell visited Johnson's house with Barry several years ago, during a period in which Barry and Johnson had a personal relationship.

The grand jury activity followed two days of visits by FBI agents to the contracting office of DHS. At least 10 agency officials were questioned by the agents or testified before the grand jury this week about a variety of alleged contract irregularities.

A number of the officials were asked what happened to the initial contract form for a contract awarded in May to B&C Management Consultants Inc., a firm set up by an undercover FBI agent with an unwitting Detroit-based businessman, Warren E. Barge Jr. FBI agents also asked how the contract could have been processed without the required signatures. A second contract awarded in March to B&C also lacked the required signature of an agency director or deputy director.

Sources have said that federal authorities are attempting to determine whether Rivers and Clyburn took bribes in return for helping B&C obtain agency contracts.

Bryon C. Marshall, deputy director of DHS, said yesterday that he first learned the original 62 form was missing in May during a weekend review of the contract file. Marshall said he took the file out during the weekend in an attempt to pull together the documents, which had been subpoenaed the previous Friday.

Marshall said neither he nor John Clark, the agency's acting chief of contracts, could locate the form. But Laverne Foster, a DHS contract specialist, said in a written statement yesterday that she discovered the document around July in a pile of papers on top of an office file cabinet.

Foster said she turned the document over to Clark, who told her to put it in his file cabinet. She said she realized authorities were looking for the form after listening to a news program Thursday night that quoted a Washington Post story.

Clark said in a statement that he had forgotten about the document until he talked to Foster yesterday morning. Marshall said he didn't believe anyone attempted to conceal the document.