School board member Marian Greenblatt likens the distribution of the races in Montgomery County to a three-color rainbow arching over the District of Columbia line.

Closest to Washington is a red-hued band, representing the county's highest concentration of minorities in the Silver Spring area, followed by a pink admixture of groups just below the beltway. Above the beltway, where minorities are scarce, is "pale pink."

"Whatever has happened is due to natural housing patterns," said the politically astute leader of the school board's conservative majority.

Greenblatt and her fellow conservatives on the board have directed Superintendent Edward Andrews to come up with a school closing plan that will have attendance areas follow these housing patterns more closely in a return to "neighborhood schools." The board would also like to minimize the busing of children for "social goals" while "keeping in mind the goals of integration," Greenblatt said.

But some white parents whose children are enrolled in three school groups attended by some 15,000 students in the "pink" area fear that the board aims to destroy their own unique solutions to the problem of racially imbalanced schools.

And black community leaders and dissident liberal board members charge that the board's intentions and recent actions signal an end to a tradition of harmony in race relations -- at least as far as the school system is concerned.

According to Vicki Rafel, a parent who has worked closely to organize and maintain the Rosemary Hills cluster of seven racially mixed elementary schools, "there may be some real resistance in the pink area."

In 1975 the school board initiated its Quality Education/Racial Balance policy because of concern about high minority enrollments in some schools and the possibility of federal intervention.

The policy set a guideline of 50 percent minority enrollment in a given school to trigger board action to bring about integration. The board also set up the first "cluster" of elementary schools, using school busing and grade reorganization to mix students of different races and backgrounds.

Participation in the first cluster, centered around Rosemary Hills Elementary School in west Silver Spring, was mandatory for children living in the area.

Another large cluster was formed in 1976 in the Takoma Park area, but participation was voluntary. That cluster included eight schools, at least three of which had minority concentrations approaching 70 percent.

A third cluster, also voluntary, was set up in the New Hampshire Avenue corridor to spread minority students from New Hampshire Estates Elementary among three other schools.

The integration programs did not affect most of the county's 123 elementary schools and affected none of the secondary schools, which remain neighborhood schools.

Rosemary Hills elementary had a 90 percent enrollment of minority children, most of them black, before it was included in a cluster of six other schools.

Rosemary Hills was converted to a school for kindergarten through second grade. Predominantly white Chevy Chase and Larchmont elementary schools nearby offered only grades three through six. (Larchmont has since closed.)

Students from the predominantly white areas join black students at Rosemary Hills for their first three years. Minority students from the Rosemary Hills area go to Chevy Chase and Larchmont for the last three elementary grades.

As a result, the minority percentage at Rosemary Hills was about 55 percent last year, although school officials had hoped it would be lower.

"I think the kids are much better off with the cluster than without," said Rafel, whose youngest son is a sixth grader at North Chevy Chase Elementary, also part of the Rosemary Hills cluster.

"It's been a great success," Rafel continued. "Academically it's hard to prove because there's no base data, but I think that the children are much more socially comfortable now with children of other backgrounds."

Created to alleviate minority concentrations in excess of 60 percent in some schools, the Takoma Park cluster offers unusual "magnet" instructional programs such as French immersion, unstructured "continuous learning" and a special science program to attract white parents to the schools.

The Takoma Park cluster also relies on elementary grade reorganization to mix students of different races.

Greenblatt said the school system needs to return to traditional elementary schools and to curriculum- and instruction-tightening measures to improve test scores. Score slippage, she said, has been fostered by liberal education policies begun "in the 60s when everything caved in."

If the clusters are dismantled, the schools will return to their pre-1975 pattern, according to Loretta Webb, head of the system's Quality Integrated Education program. Rosemary Hills would return to a 90 percent minority enrollment and several Takoma Park schools to 70 and 75 percent minority. Several non-cluster schools in the southeastern part of the county now have minority populations in excess of 50 percent, Webb said.

Under the guidelines approved by the school board last month the board is not obliged to consider a remedy for racial imbalance until the percentage of minority students in a school exceeds 60 percent. The 60 percent guideline is derived from a formula based on the overall percentage of minorities in the school system, currently 22 percent. As that percentage rises or falls, so will the maximum limit of concentration allowed.

Because the minority percentage of the school system is increasing by about 2 percentage points a year, liberal school board member Blair G. Ewing charged, the board's action will deliberately resegregate the schools.

"The evidence of worsening race relations in Montgomery County is clear for all to see . . . it is clear to me that the majority members of the board appeal, in steadily less subtle ways, to the worst instincts of some of their fellow citizens," Ewing said recently.

County NAACP president Roscoe Nix is confident, however, that the whites in the "pink" areas of the county and others will be among the strongest advocates of keeping integration policies intact because "it is in their interest."

"The major confrontation with the board will be from the white community. I see (blacks) forming very viable alliances with white groups about the issues of concentration," Nix said. "There have been a lot of white groups who worked very hard to make integration work down county," he said.