An investigation ordered by the Montgomery County Council has concluded there is no evidence that Planning Board nominee John P. Hewitt knew of or condoned segregated work facilities that existed in a parks maintenance yard while he was a top parks administrator in the 1960s and early '70s.

The 13-page report released yesterday concludes that there were separate lounge and lunchroom facilities for black and white workers at the Meadowbrook Yard during at least part of Hewitt's tenure with the Maryland-National Capital Parks and Planning Commission.

Many employes, including on-site managers, knew about the practice, the report said. But there is no evidence that Hewitt was ever told about or was aware of the segregation, even though he may have visited the facilities, according to the report by Andrew Mansinne Jr., director of the council's Office of Legislative Oversight.

Hewitt, a Silver Spring real estate agent whose nomination to the influential Planning Board has been sidetracked and his reputation tarnished by the racial allegations, hailed the report as a personal vindication.

County Executive Sidney Kramer, who had stood behind his choice of Hewitt throughout the month-long controversy, said the report "clears the air" and called for prompt confirmation of Hewitt.

But Montgomery County NAACP President Roscoe R. Nix, who raised the issue of segregated conditions at the Meadowbrook Yard, termed the report inconclusive and said he hoped the council would refuse to confirm Hewitt's nomination when it meets this afternoon.

An informal poll of the seven-member council yesterday showed three members favoring the 64-year-old Republican's nomination, with two members opposed and two undecided.

Mansinne's report is the result of a two-week investigation that included research in public documents and interviews with more than 30 witnesses, most under oath, in an attempt to reconstruct events that occurred at least 14 years ago in a Chevy Chase service yard operated by the commission that serves Montgomery and Prince George's counties.

The report provides a glimpse into a little-known chapter of the past of a county proud of its recent stance on civil rights. It examines the practices and personnel of the Meadowbrook Yard in Chevy Chase during the mid-'60s and early '70s. Hewitt, who retired from the commission in 1974 after 29 years, held two top management jobs during this time: He was director of parks from 1957 to 1971, and was executive director of the bicounty commission from 1971 to 1974.

The report describes, starting in the mid- to late '60s, a work area with better conditions and with more amenities for whites than for blacks. There was no written or oral policy separating the work force, according to the report, but black employes felt unwelcome in the white area, and no action was taken by managers prior to 1974, when eight black workers filed a complaint with the Equal Employment Opportunity Commission. The facilities were eventually dismantled.

Hewitt told Mansinne that as director of parks he visited the Meadowbrook Yard about once a week and that he probably had been inside every building in the yard except one residence. He could not, however, recall specifics of any building and he testified he could not recall "ever visiting any room . . . in which the occupants were either predominantly white employes or predominantly black employes."

Nix said he had trouble believing that Hewitt didn't know the facilities were segregated after having been exposed to them. "Is the purpose here to certify Mr. Hewitt a cretin?" Nix said.

If the council confirms Hewitt to the $12,600 post of citizen-planner, Hewitt can take office tonight as the Planning Board meets on Silver Spring growth issues.