A contract for the school district's administrators was given a failing grade Monday night by the Representative Town Meeting.

By a razor-thin margin of 21-20, the RTM rejected the three-year pact, sending it to binding arbitration. This is the first time in about two decades that a contract with one of the local school employee unions has been rejected by the legislative body, according to town officials.

Under the proposed agreement, which would be in effect from July 1, 2015, to June 30, 2018, the 38 school administrators would receive wage and increment increases of 2.65 percent the first two years and 2.66 percent in the final year. Employees' share of insurance premiums would increase 1 percent each year, with the employees paying 25 percent of medical insurance and the prescription drug plan by 2017-18 and 23 percent of dental insurance premiums by the same date.

The union represents headmasters and housemasters at the high schools, principals and assistant principals at the town's other schools, as well as guidance coordinators, athletic directors and curriculum leaders.

RTM member Chris Tymniak, R-9, said, "Millions of Americans, and thousands of Connecticut residents' health-care plans have been changed, through no fault of their own." He said the town's negotiators should have drawn a line in the sand regarding school administrators' health plans, and questioned why a high-deductible policy, with a health savings account, was not offered.

District officials said because of employee demographics, a high-deductible plan would not have saved the town any money. With this negotiated settlement, the town will save an estimated $130,000 over the three years, according to officials.

"To me, it's rich, unnecessarily rich," said David Mackenzie, R-3, adding that the town needs to take into consideration the "cadillac" tax the health plans will be subject to in 2018. "I guess we're just hoping we'll figure out."

In response to Tymniak's call to let the contract go to binding arbitration, Sheila Marmion, D-6, said such a move could "bite us in the butt."

The arbitration panel is able to consider any previous offers made by either side, and does need to find middle ground.

"In the end, we could get a deal for the administrators that is much more costly," Marmion said. She said progress is being made to increase the employee share of medical premiums. "It may not be as fast as you like it," she said, but added, "It is real progress."

But Gaylord Meyer, R-1, said her constituents are telling her to stop local tax increases and reduce the town debt, which she pegged at $28 million.

First Selectman Michael Tetreau quickly corrected Meyer, noting the town finished the last fiscal year with a surplus and is not $28 million in debt. Ellen Jacob, R-9, said Meyer was referring to the town's debt service, which Tetreau said which is between $26 and $28 million.

"We do have a huge capital program in from the Board of Education this year," Jacob said. "We have two large school projects. We have to look at the whole picture."

The school board is reviewing a non-recurring capital projects request of about $5 million. Of that, $3.2 million would be for improvements and upgrades to security at all town school buildings.

Kevin Hoffkins, D-7, said comparing benefits received by public sector employees to those in the private sector is comparing apples and oranges.

"We're not the private sector," he said. "We have restrictions of state law and bargaining units."