Council Speaker Christine Quinn has not yet weighed in on Chelsea Market's plan to add 250,000 square feet of office space atop its building and build a 12-story hotel nearby. But behind the scenes, insiders said that Ms. Quinn remains uncomfortable given the mounting criticism over the proposal and that she has pushed Jamestown Properties—the market's Germany-based owner—to make the project more palatable to opponents before the City Planning Commission certifies it later this month, according to Crain's Insider . “Chris has taken the temperature of the community on this,” said one insider. “There's not enough in it for her to simply go against them.” As it stands, the plan would already commit Jamestown to pony up more than $17 million for improvements to the nearby High Line. The developer, in exchange, would receive a special zoning variance that would allow it to build an eight-story glass office tower above Chelsea Market—to the dismay of activists and preservationists who believe the West Side neighborhood has been overdeveloped in recent years. Some critics also complain that the High Line concession offers little benefit to residents of the neighborhood. Last month, Community Board 4 outlined a host of possible goodies the developer could provide, including money for affordable housing and other parks in the neighborhood. Representatives from Jamestown Properties and Ms. Quinn's office declined to comment. Initially, Jamestown refused to alter its proposal. Now, at Ms. Quinn's behest, the big landlord appears poised to offer significant concessions. Sources familiar with the negotiations said Jamestown could be willing to forgo its 90,000-square-foot boutique hotel on Ninth Avenue and build additional office space in its place. The developer might also agree to set aside ground-floor retail in Chelsea Market for artisan food vendors and other independent businesses. Despite having a seat at the table during negotiations, Save Chelsea, a leading opponent, plans to fight the proposed expansion through the review process. “We are standing firmly against this,” said group leader Leslie Doyle. “No matter what.” This week, community newspapers Chelsea Now and The Villager issued a scathing critique of the expansion and urged Ms. Quinn and the Bloomberg administration to “deep six” it. Proponents, meanwhile, remain confident that Ms. Quinn will do no such thing. The project, according to projections, could drum up 1,200 construction jobs, 3,600 long-term jobs and generate $1.35 billion in economic activity a year. “This is a no-brainer for her,” an insider said.