TRENTON -- A subcontractor is complaining to federal officials after she says she was fired from the $35 million Roebling Lofts project amid pressure from the unions, mayor and developer.

Marilyn DaBronzo, president of M&R Insulation Systems, had been awarded a $105,500 contract to do duct and pipe insulation. The work was slated to begin next month, but she was told last week by HighTec HVAC, the project's mechanical subcontractor, that she was being terminated.

In a Friday letter sent to the U.S. Department of Labor's Office of Inspector General, she alleges there was collusion between Local 89 of Heat and Frost Insulators and Allied Workers, Fred Dumont, the union's business manager, and Trenton Mayor Eric Jackson to get rid of her.

"I was told that it is so political and so high up in Trenton government that he has to revoke my contract or else," DaBronzo wrote.

Michael Castelli, director of construction at HighTec, said the directive to fire DaBronzo came from the construction manager, W.S. Cumby, and the developer, HHG Development Associates.

"For whatever reason, I was not allowed to use them. The owner asked that they not be used on the project," Castelli said, adding that he has previously worked with DaBronzo. "The unions said they would match (M&R's) price. ... I really don't like what happened, but it's not my call."

He said the mayor's name was thrown around, but that he never spoke with him.

On Monday, Jackson vehemently denied DaBronzo's claims, saying he didn't even know who she was and that neither he nor his staff would ever get involved with developers on that level.

"I don't know how my name got into the mix, but it's totally unfounded," he said. "I don't tell those private folks how to run their business or pressure them to use anybody."

Jackson said that every so often he talks with union leadership -- Dumont included -- about how to boost job prospects for city residents.

"I want local labor where we can get them ... but I don't give them any quotas," he said. "I don't do that and I won't begin that."

David Henderson, one of HHG's principals, said they had a conversation with W.S. Cumby after learning that the labor departments in New Jersey and Pennsylvania recently debarred M&R Insulation from bidding on public works projects for 18 months and three years, respectively.

"We were concerned. We became privy to this information and our (construction manager) had a conversation with the sub and that was the outcome," Henderson said. "We're very committed to our project paying people fairly and obviously this was a red flag. ... This is a sub of a sub of a sub and it was their call as to what to do."

Even though M&R's New Jersey public works contractor registration is revoked until January 2018, the state allowed them to complete four projects, the Roebling Lofts being one of them.

"I have every right to do that job," said DaBronzo, who also brought her concerns to the FBI's Trenton field office. "Who is the political machine? Who is getting the contract? ... It's the union applying pressure to the government because they give money to these politicians."

During Jackson's mayoral campaign, he picked up endorsements and contributions from nearly a dozen building trade unions -- including $500 from Local 89 and $2,000 from the Mechanical and Allied Crafts Council of New Jersey, of which Dumont serves as financial secretary.

DaBronzo said that for years, union workers and Dumont have filed complaints after complaints against her business.

When she started her business in 2005, she was part of Local 89, but two years later, the union severed ties with her. She claims Dumont, who she says had an "ugly divorce" with her husband's sister, has long had a personal vendetta against her.

She said she was forced to settle the cases because she couldn't afford to fight them.

"I just want to do my work," she said.

For his part, Dumont said there are no truths to DaBronzo's claims. He sits on the board for the state's Economic Development Authority, which awarded HHG $16.1 million in tax credits, but said that was the extent of his involvement in the project.

Cristina Rojas may be reached at crojas@njadvancemedia.com. Follow her on Twitter @CristinaRojasTT. Find NJ.com on Facebook.