A federal judge here has returned to Montogomery County the power to reject or approve the local portion of a federally sponsored nationwide health services plan.

The opinion means that Montogomery County has won a year-long battle with the U.S. Secretary of Health, Education and Welfare over whether the County Council should have final approval over the long-range health plan that a seprate governing body was charged with developing.

The decision came just three weeks before county public hearings on a draft version of the local plan.

The county had challenged regulations ussued by HEW Secretary Joseph A. Califano Jr. establishing the structures and powers of the local health planning agency and its governing boards under the federal National Health Planning and Resources Development Act of 1974.

Montogomery County is one of the few areas in the country which was designated as a "health planning area" without crossing county lines. The county argued that its County Council, which also was designated the Health Systems Agency for its area, should have final approval and veto powers over any plans of the governing board.

But Califano said the county would not get any funds under the law until all its power to approve or reject the plan were relinquished to the appointed, 23-member governing body.

In February 1977, the county filed suit against HEW, arguing that the HEW secretary's regulations conflicted with the actual wording of the law that they also were an unconstitutional intrusion upon local governing powers.

"We felt that if there was something wrong with the plan, the public would hold the elected officials accountable, even though the elected officials had no say in the plan," Assistant County Attorney Nathan J. Greenbaum said.

Judge Frank A. Kaufman, in a lengthy opinion released early in April, said the secretary had "exceeded his statutory authority" in issuing the regulations.

Kaufman said the section of the federal law under dispute does not say that the Health Systems Agency, in this case the Montgomery County Council, "is to be subordinate to the governing body." Even if the law could be interpreted that way, Kaufman added, "the legislative history teaches otherwise."

Kaufman, however, rejected the argument that the law itself was unconstitutional or that it intruded upon the power of local government.

The draft version of the plan for Montgomery County is a statement of the county goals in health planning and a guideline of what currently is available and what is needed for the future, according to a spokesman for the local health systems planning board.

The board will conduct a public hearing on the draft plan at 8 p.m. May 1 at Richard Montogomery High School.