The custodians learned of the mayor's decision to outsource June 15, after they failed to come up with a plan that would match the more than $1 million in savings the administration claims it will realize by switching to a contractor.

In an e-mail sent to the aldermen and school board members after the decision was announced, Chief Shop Steward Peter Blaikie said the union had offered to sacrifice nine custodians, take no raise for seven years and increase their insurance contribution to the maximum 25 percent.

"[Curtatone] told us that still wasn't good enough and that we are out of work," Blaikie said in the e-mail.

Blaikie also called Curtatone a "hypocrite" for supporting striking Tufts University custodians during a recent labor dispute, adding that if the Boston Housing Authority loses a lawsuit over its outsourcing of 18 employees Somerville could see a similar suit filed.

Alderman-at-Large Bruce Desmond pressed Director of Personnel Jessie Baker on whether custodians could lose unemployment benefits if they refused to take jobs with the new contractor, who will be making an undetermined number of positions open for the city custodians.

While Baker said the city can't control the contractor's reporting of job offers made, the city won't punish those who choose not to take employment with the new company.

"We're not going to protest their unemployment benefits," Baker said.

Alderman-at-Large Dennis Sullivan said that while he understands Curtatone's position, he opposes the move.

"These are people that have given their life, their careers to the City of Somerville as custodians, and I respect that," Sullivan said. "It breaks my heart when I see this happening."

Ward 6 Alderman Rebekah Gewirtz challenged the mayor to explain why the custodians' counter offer was not acceptable.

"As three percent of the workforce, they're bearing 20 percent of the budget gap," Gewirtz said, referencing numbers provided in Blaikie's e-mail. "How is that not enough? I'd just like someone to please explain that to me."

When Curtatone reiterated the need for cuts and shared sacrifice, Gewirtz said he was avoiding her question, calling his lack of response a "slap in the face to school custodians."

"Many of those people are my friends," he responded. "Now, maybe not for long. Not every decision fits into my personal feelings – the law doesn't allow it."

"I know you don't like the personal side of it," he added. "Have confidence the city is moving in the right direction."