Gone is the power of a 10,000-member staff and an annual budget of $450 million. Gone are the headaches of being accountable for the day-to-day operations of the city's largest and most troubled department. And gone, too, is the defiant pugnacity with which Joseph P. Yeldell asserted his momentary return as director of the D.C. Department of Human Resources last month, saying he would go on to become the No. 3 man in Mayor Walter E. Washington's administration.

"I don't deal with pecking order," the 44-year-old former DHR director turned mayor's general assistant said last week, when asked if he still considers himself third from the top in the mayoral hierarchy. His boss doesn't believe in pecking orders, either. "I'm the only one around here with a number," Washington said. "I'm No. 1."

So it is that the new Joe Yeldell has emerged in past weeks as a low profile, team player on the mayor's squad, drawing the same $47,000-a-year salary he made as DHR director but without the many problems. "I like it," Yeldell concedes.

It was a month ago this week that Yeldell became general assistant to the mayor following a four-month suspension as DHR director amidst allegations of widespread mismanagemetn adn conflict of interest.

As is the case with several othe special assistants to the mayor, it is difficult these days for a regular city hall observer to tell just what it is Yeldell does.

He describes his own responsibilities as including development of a residential job corps center for city youth, studying whether the city's Advisory Neighborhood Commission system needs to be overhauled and acting as the mayor's liaison with a newly appointed committee on minority contracting.

His job description gives Yeldell authority to perform a broad variety of tasks, ranging from acting as the mayor's go-between with the White House to being a mayoral contact with the Office of Municipal Audit and Inspection, which investigated the allegations against Yeldell for the mayor.

Yedell, sources said, appears to have made a conscious effort to avoid stirring up conflicts with other mayoral advisers, some of whom dislike him.

"He's trying to put all that behind him," one Yeldell supporter said of the man who was placed on leave of absence for defying a mayoral mandate and staging a defense rally in response to the mismanagement charges.

Yeldell did not bother to assert a right to office space in the mayor's fifth floor complex on the east end of the District Building. Instead, he will have offices in the building across the street that houses the National Theater. Until that office is ready, Yeldell operates out of his old office in DHR and has occassionally been seen in a DHR car.

There were times months ago when Yeldell's return to city government was viewed as temporary, a staging area for quick employment later in private industry. But some persons close to Yeldell are now saying tht he may be rethinking such a quick departure. Some say the private options never were available, and $47,000 is a hard salary to duplicate.

In the meantime, if Yeldell is concerned about the U.S. Attorney's stepped-up investigation of Yeldell's ties with millionaire parking lot magnate Dominic F. Antonelli Jr., or the several thousand dollars in lawyers' bills he has incurred over the past few months, he's not showing it publicly.

Another detail. This time it's Tina C. Hobson, the widow of City Council-member Julius Hobson, who has been detailed from her job at the Federal Energy Administration to the office of Esther Peterson, President Carter's special assistant for consumer affairs.

Mrs. Hobson says that the detail will not affect her final decision on whether to run for City Council as an independent in the special July 19 election to fill her husband's seat. She threatened to do that last month, after the Statehood Party ignored her husband's final requests and chose Hilda Mason instead of Mrs. Hobson as his temporary successor on the council.

Mrs. Hobson has yet to pick up petitions to run in the special election and has only two moe weeks to get 3,000 signatures if she plans to run. Still, she said Monday, she doesn't plan to make up her mind until sometime next week.

In her new position, which could become permanent, Mrs. Hobson will help assess the affect of the President's proposed energy plan on American consumers.

The movers had barely begun to transport Nadine Winter's furniture to her new quartes on the first floor of the District Building last week when Wilhelmina Rolark kicked off the scramble to claim Winter's old space on the fifth floor next to Rolark's.

By week's end, Rolark had pulled off a coup d'etat of sorts and quickly scuttled - at least ofr the moment - Chariman Pro Trmpore Willie Hardy's plans to seize the newly vacated space.

"This is a non-violent confrontation," Rolark (D-Eight) said lightly at one point, as she sat outside the doorway to Winter's old office claiming squatter's rights to the newly available office territory.

Hardy (D-Seven) has les offices space than any other council member. Hardy's plan, as the person in charge or reallocating Council space, was to give Rolark these small quarters and take Rolark and Winter's old space for her own.

But when moving day arrived for Winter, Hardy was out of the District Building. As soon as the movers took Winter's furnishings from her office. Rolark camped outside the door to stand watch while the desks of her Employment and Economic Development Committee staff were moved up from the second floor.

By the opening of business on Friday Rolark and her staff were in place, well enough entrenched, in fact, to have gotten around a memo from the day before by Council Chairman Sterling Tucker declaring a moratorium on any moves except Winter's.

Wilhelmina Rolark called it a victory for the power of positive action.