In an unprecedented action, a Maryland state hearing examiner yesterday found that the Montgomery County School Board ignored its own commitment to integrated education by voting to close Rosemary Hills Elementary School and to alter boundaries of Montgomery Blair High School.

Concluding that the board acted in an arbitrary or unreasonable manner in several key instances where racial balance was an issue, Examiner Mitchell J. Cooper urged the Maryland Board of Education to overrule the county board, an action that it never before has taken in a school closing appeal.

The state board scheduled a brief hearing for June, after which it will make a final decision.

Yesterday's politically explosive finding sets the stage for a battle royal in upcoming elections between the majority of the board, which plans to campaign on its policies, and challengers who backed the appeal to the state.

Cooper said the board deviated without legitimate reason from the recommendations of Supt. Edward Andrews and from the board's own criteria for changing boundaries and closing 30 of the county's 177 public schools. He said the board acted without giving affected communities a fair chance to comment before the decisions were made.

"While the racial balance (policy) does not mandate the achievement of specific goals by a specific date," Cooper noted that it requires "good faith efforts by the community, staff and board" to try to educate the county's children in a racially and economically integrated setting. His comments were contained in a voluminous set of opinions released yesterday.

Montgomery board member Marian Greenblatt said she was "very disappointed" that Cooper disagreed with the panel's actions in several cases. "But it's up to the state board now, and we will certainly present our case to them," she said.

Cooper's opinions were hailed as a significant victory by critics who have spent three years fighting a series of board actions they contend have tarnished Montgomery County's reputation for racial tolerance and harmonious integration.

"This suggests that the board has been acting so arbitrarily and so ideologically that they have ignored the community and have thought that due process was unnecessary," said Roscoe R. Nix, president of the county NAACP and a former school board member. "It will be very difficult for the state board to ignore the hearing examiner in this many decisions."

Cooper, a Washington attorney with 10 years experience as a hearing examiner for the state, heard several days of testimony in February and March from attorneys, school officials and community residents.

If the state board agrees with Cooper, Rosemary Hills, located in a predominantly minority area, would remain open and the six-year-old effort at pairing schools and busing students for integration in the area would continue. The county board has voted to close Rosemary Hills and scatter its predominantly minority students to four elementary schools.

Cooper urged the state board to reverse the county plan to divert students in three predominantly white elementary schools from Blair in Silver Spring, which has the highest minority enrollment of any high school in the county. The superintendant specifically had proposed sending those students to Blair to help reduce minority percentage, now at 58.6 percent, and maintain a steady enrollment.

Cooper also rejected as inconsistent with the board's own stated goals its decision directing more minority students to Eastern Intermediate School, also in the Silver Spring area.

He upheld the board's decision to close Takoma Park Junior High, an action recommended by Andrews but hotly contested by the community.

"The fight is not over," vowed Faith Stern, a Takoma Park resident who has led the community's spirited effort to save its school. Peter J. Nickles, who led a team of lawyers challenging the board's decisions in the Silver Spring-Takoma Park area, said he hoped the state panel would concur with all of Cooper's recommendations except in the case of Takoma Park.

"Takoma Park is the one we want them to pay special attention to," he said. "Otherwise, he showed a lot of independent thinking."

In recommending that Rosemary Hills remain open, Cooper challenged assertions by Greenblatt that the school's comparatively lower test scores were justification for closing. "One cannot appropriately compare test scores from school to school without taking account of the disadvantages a given group of children bring to a given school," Cooper wrote.

The examiner's main objection was to the board's decision to stop busing children from the predominantly white Chevy Chase area while forcing Rosemary Hills students, largely minority, to ride buses beyond their neighborhood for most of their school years. The Rosemary Hills and Chevy Chase pairing, established in 1976, involves sending Chevy Chase students to Rosemary Hills through the second grade and Rosemary Hills pupils to Chevy Chase for the upper elementary grades.

"Was there a valid reason for board action which not only substitutes one-way desegregation for an existing pattern of two-way desegregation, but also disperses the minority children to four different schools?" Cooper asked rhetorically.

Greenblatt said Cooper "missed the whole point" in regard to Rosemary Hills. "We have better integration" under the board's plan at the four receiving schools "than exists now," she said.

In explaining its decision to close Rosemary Hills, the board's majority also stated its preference for kindergarten-through-sixth grade schools throughout the county, rather than the K-2 and 3-6 pattern that exists at Rosemary Hills-Chevy Chase and several other pairings. Cooper said testimony, including that of the superintendant, had failed to support their view that a K-6 structure is educationally superior.

The examiner's conclusions concerning the Blair area come amidst a bitter debate over the school's survival, which never was in question until the board decided last fall to depart radically from the superintendant's proposal. With the highest percentage of minority and foreign language students of any high school in the county, Blair parents have been pushing the board to bolster the academic program and provide added resources.

The board's actions on Blair have upset many students and teachers at Blair, especially many of its minority students. Tommy Broadwater, president of the Blair Parent Teacher Students Association, said his two children attending Blair feel "that nobody wants them." A recent article in the school newspaper, Silver Chips, forced board president Eleanor Zappone to recant assertions that students from other schools would enroll in parochial schools rather than attend Blair.

Cooper contended that the board's decisions to change attendance boundaries for Blair would reduce enrollment from 1,750 to 1,350 within a few years, jeopardizing the diverse curriculum it now must offer to satisfy its broad mix of students. He noted also that the minority percentage would increase under the board's plan, whereas it would have decreased to 50 percent had the superintendant's recommendations been followed.

Under board guidelines, efforts must be made to lessen minority concentrations if a school's minority percentage exceeds 60 percent. The board had angered many when it raised the threshhold of concern last summer from 50 percent.

Cooper said the board "arbitrarily deviated from its policies to the disadvantage of Blair."

In the aftermath of its decision to change Blair's boundaries, the board considered the possibility of closing the school, but has postponed any decision until after the election.

Cooper was equally critical of the board's boundary changes in the Eastern Intermediate School area, also inside the Beltway. He noted that the new boundaries would increase the school's minority enrollment by 18 percent compared to a 10 percent increase under the superintendent's plan.

While accepting the board's boundary changes involving the East Silver Spring and Piney Branch elementary schools, Cooper urged that steps be taken to reduce their minority percentages by at least a tenth.

Cooper's recommendations are expected to rekindle debate over racial balance and school busing in Montgomery County. These issues, and the board's general handling of the school closings, also have taken on political overtones with four board seats up for grabs later this year and with Greenblatt, whose term does not expire this year, considering a congressional challenge to U.S. Rep. Michael D. Barnes (D-Md.).

A number of community activists already have formed political committees with the specific goal of ousting the faction led by Greenblatt. Assisting them will be Blair Ewing, a dissenting board member who repeatedly has challenged his colleagues' decisions on race-related issues.

"Montgomery County voters will make changes in November," Ewing said, pledging his support to such efforts. His term runs until 1984.

Greenblatt forecast just the opposite outcome. "I certainly support those people with similar views and want to make sure that philosophical outlook is sustained," she said.

Not all the closures stirred ideological controversy. In a case unrelated to racial balance, Cooper said Radnor Elementary School in Bethesda should remain open instead of Bradley Elementary, which needs $2 million in renovations. Although Andrews originally proposed such a course, the board's decision to close Radnor instead generated a storm of criticism in the community.

In four other appealed cases, in which race was not a primary issue, Cooper upheld board decisions.