Groton — The Groton Board of Education, which moved 16 percent of its elementary school students in September to correct a racial imbalance and crowding in one school, has been cited by the state for a racial imbalance in another school.

A 2013 state enrollment report showed that Claude Chester Elementary School is racially imbalanced, enrolling 68.2 percent minority students. Three other Groton schools - Catherine Kolnaski Magnet School, Northeast Academy and S.B. Butler Elementary - have pending imbalances.

A school is considered racially imbalanced if the minority population is 25 percent higher or lower than the district average in comparable grades. A school has a pending imbalance if the minority population is 15 percent higher or lower than the district average.

The district average in Groton is about 42 to 43 percent minority students in elementary school, depending on the grade.

Groton filed a plan to correct the imbalance at Kolnaski Magnet, then amended it last year by redrawing the district's attendance zones.

"Although the imbalance at (Catherine Kolnaski Magnet School) was substantially reduced, Claude Chester is now imbalanced," said a May 12 notice from Education Commissioner Stefan Pryor to Groton Superintendent Michael Graner.

The state enrollment report shows the minority populations at Kolnaski Magnet, Northeast Academy and S.B. Butler are about 58.3 percent; 24.9 percent and 27.3 percent, respectively.

Groton must submit a plan to correct the imbalance at Claude Chester within 120 days, or by Sept. 12.

The Board of Education is scheduled to discuss the notice at its next meeting, at 6 p.m. Monday in the Robert E. Fitch High School band room.

"It just seems that the issue continues to come up," said Deborah Johnson, outgoing chairwoman of the Groton Parent Council.

She said parents would not accept another redistricting before Groton has a long-term plan for its schools.

"It just really upsets friends, it really upsets the families who are affected," she said.

But she said the issue could help move plans for the schools along. The school district hosted a community workshop in May to discuss future construction, and the recommendations of that group could help deal with the state, Johnson said.

"If they could present something, it may buy them time," she said.

The recommendations would build one new middle school, possibly adjacent to the high school, turn Carl C. Cutler Middle School and West Side Middle School into elementary schools, and close Claude Chester, S.B. Butler and Pleasant Valley elementary schools.

The workshop goal was to decide what future school buildings should include to accommodate programs and academics - such as the type of media center, for example, and to discuss the existing buildings.

The Board of Education is expected to be briefed on the details Monday. The board would then approve or change the recommendations and forward them to the town School Facilities Task Force. The plan would then go to the Town Council, Representative Town Meeting and ultimately to voters at referendum.

The school board adopted last fall's redistricting plan based on recommendations from the consulting firm Milone & MacBroom, which continues to work with Groton.

The firm hoped redistricting would correct the racial imbalance enough to last for two years, Planner Mike Zuba said Thursday. But he said planners also had to move students out of Kolnaski to relieve crowding, which brought Claude Chester to within a few students of being unbalanced.

"We knew we were cutting it close," Zuba said.

Groton has been grappling with racial imbalance since at least 2003, when Kolnaski Magnet School was cited. It tried a magnet program with limited success, and two years ago considered whether to fight the state's racial balance law as outdated and unfair.

If a school is found to be racially imbalanced, the district must submit a plan to the state board of education to correct it, Education Department Spokeswoman Kelly Donnelly said. The state board would then approve the plan or request a new one.

"Once a district submits a plan and it's approved by the board, we understand that it might take a couple of years to see the plan take hold," Donnelly said.

If a district refuses to comply with the law, the state department of education could file a complaint with the state board, recommending the district be cited for failing to uphold the state's educational interests and ordered to produce a plan.

If the district still refused, the state could take the school district to court.

d.straszheim@theday.com