Mayor Marion Barry's administration plans to hire a panel of national purchasing experts to study the District's long-troubled purchasing system in response to recent allegations of waste totaling millions of dollars, competitive bidding abuses and, in one department, misuse of city funds.

City Administrator Thomas Downs said yesterday that "it's highly likely" within the next few weeks that the city will finalize a contract for a study with the National Academy of Public Administration, a nonprofit, congressionally chartered organization modeled after the National Academy of Sciences.

Don Wortman, the academy's acting president, said the study would cost between $75,000 and $125,000 and take three to four months. He said academy officials now are putting together a panel of about six or seven experts to be headed by Elmer B. Staats, who won high praise as comptroller general of the United States from 1966 to 1981.

Under Staats' leadership, the General Accounting Office repeatedly pointed out waste and mismanagement in the District's purchasing and warehousing operations. The GAO came to the same conclusion as did a congressionally appointed commission in 1972 and the D.C. City Council in 1976: The city should create a strong central authority in charge of buying and storing in order to save money and control abuses.

In 15 years, those recommendations never have won the support of top-level city officials, largely because of the political and logistical problems that a full-scale reorganization of the system inevitably would entail.

To some city officials and council members, complex questions remain about how the city should best buy and store what it needs.

Downs and at least one council member, for example, question whether the city must transfer as many as 250 purchasing and warehousing employes, now scattered throughout various city agencies, to one department -- as the congressionally appointed commission recommended -- to achieve efficiency and control.

"There are no quick answers," said Downs. He said the study will focus on "what is the proper role for centralized procurement."

The decision to call for a study follows an aborted attempt by some City Council members last month to force Barry to revamp the system.

At least half a dozen council members had expressed support for a bill to centralize operations by transferring employes who spent more than 50 percent of their time on procurement to the Department of Administrative Services. But the bill's sponsor, council member William Spaulding, (D-Ward 5), withdrew the measure from the council floor after last-minute negotiations with Barry, who had strongly objected to some aspects of the proposed legislation.

At the time, some council aides speculated privately that Spaulding had bowed to the mayor's wishes, though one of the bill's supporters said the measure simply wasn't ready to be put to a vote. Spaulding said then that he wanted to take the bill back to the Government Operations Committee to resolve lingering questions. He responded angrily to suggestions that he was doing the mayor's bidding.

Council member Charlene Drew Jarvis, (D-Ward 4), said she was surprised the administration was seeking a study now "given the extensive work the (Government Operations) Committee has already done on this subject. The city had ample time to make recommendations . . . last year."

Downs said he conceived the idea of a study because "there seem to be so many ready-made experts in procurement that I thought it was time we got some true procurement experts to give us some advice."

Downs apparently was referring to a series of stories last August, in which The Washington Post reported that the District's decentralized and lax operations led to substantially higher prices for supplies than paid by surrounding jurisdictions and a pattern of abuses of competitive bidding rules.