The D.C. City Council yesterday approved by a narrow margin plans to establish its own 15-member task force to study whether the city's massive and troubled Department of Human Resources should be broken up and reorganized.

After a move to postpone indefinitely the appointment of the panel fell only one vote short of succeeding, the Council approved Chairman Sterling Tucker's plan by a 7-to-5 vote.

The narrow margin of victory for the resolution, which had received only minor opposition when it first was proposed, surprised even Tucker. "There was nothing controversial about it; we had already agreed to have a task force," he said afterward.

Politically, the vote was a close call for Tucker, whose margin of victory included the votes of the Council's lone Republican (at large member Jerry Moore) and Marion Barry (D-at large), who is considered the major rival to Tucker for the 1978 Democratic mayoral nomination.

[TEXT OMITTED FROM SOURCE] on assertions that it did not spell out how much the task force's expenses would be and where the money would come from. "It's just a blanket resolution," said Nadine Winter (D-six). "There are no other task forces or resolutions that are open-ended, and here we are writing a blank check."

Tucker assured the Council that any funds appropriated to pay for the task force must be approved by the Council before they could be spent. Council members also expressed reluctance over adopting the resolution because Mayor Walter E. Washington already has established a 32-member task force to carry out the same function.

"It's unnecessary, it's a witch hunt and it's duplicating," said Douglas E. Moore (D-at large).

Tucket has not disclosed who the members of the task force will be, but his resolution stresses that there should be significant representation on the panel by local persons. Many of those on the mayor's task force are national figures.

The mayor's task force is headed by Philip J. Rutledge, the first director of the agency and the architect of its present structure. The city is providing $85,000 from DHR funds towards the task force's operating costs.

Several Council sources discouraged views that Tucker's close victory on a pet resolution indicates his power his waning on the increasingly politicized Council.

"Just like every other Council member, he probably is going to have to start counting his votes on every bill," a source close to Tucker said. "That's never happened here before, but I don't think it means anything more."