Jay Rourke, project manager for the Boston Redevelopment Authority, is sifting through letters from civic leaders, local residents and city and state agencies this month, trying to create a new checklist of things Corcoran Jennison should study or consider altering about their Bayside re-development proposal on Columbia Point.

Corcoran Jennison is the developer of a proposed vast new shopping and rental-apartment complex on the 28-acre site of the Bayside Expo Center. The redevelopment effort includes hundreds of shops, rental apartments and parking lots where the Columbia Point exposition hall now stands.

Among the letters submitted to the BRA is a call for expanding the amount of open space to around 10 acres from the city and the state, a call for greater detail on green building features from the city's environmental department, and a call for more information on just about everything from UNITE HERE!'s Local 26 hotel union.

Just how they re-shape the project, if at all, will be a test of each party's clout, and of the willingness of the BRA to sway the developer of one of the largest developable plots in the city.

"We are disappointed with the general lack of open space and recreational resources for new residents," said Boston Parks and Recreation Department spokeswoman Mary Hines, adding that the department will have to approve the project.

For every 1000 residents, five acres of open space are requested by the department's Open Space Impact Assessment, explains the Park Department's Aldo Ghirin in his letter to the BRA. The Bayside development, he estimates, will bring 1,700 new residents or more to the area, thus requiring nine or 10 acres of open space. The open space the project does have, he continues, sits among parking lots and roads and is more decorative in nature than recreational.

"This underserved demand will likely cause these new residents to seek active recreation resources, including those of nearby environmental justice communities," he wrote.

Ghirin's open space call was echoed by the state's Economic and Environmental Affairs secretary Ian Bowles, who also asked Corcoran Jennison to examine the possibility of eliminating the easement across the Department of Conservation and Recreation property that accesses Day Boulevard near Carson's Beach. Bowles requested the project provide a single Environmental Impact Report to the state, reserving the right to ask for a supplemental one if the first is not adequate.

The prize for most comprehensive letter may go to the city of Boston's environment department, signed by director Bryan Glascock. In it he questions more than 14 different points in the developer's assessment of its own LEED points, a green-building standard the city now requires all new large projects to live up to. Gloasock also gives detailed advice on transportation modes and energy efficiency, and even goes so far as to suggest fitting out the buildings with the infrastructure to support renewable energy generation such as photo-voltaics or wind-turbines.

Glascock said the mayor is fully behind enforcing the green standards but added that the incentive to go green is also reinforced by the free market.

"We're seeing a lot of projects going the pipeline that are going LEED Silver or Gold certified, because they see that as a marketing advantage," he said.

Lastly, among the dozens of letters was also a nine-page message from the UNITE HERE! Local 26 Boston Hotel Workers Union criticizing the developer's lack of coordination with the Columbia Point Master Plan, lack of detail in everything from building heights to wind analysis, several problems with the project's traffic mitigation plan and a need for more information about how family-oriented the development would be.

Janice Loux, the union's president, did not return several phone calls and messages for comment, but Catherine O'Neill did confirm that the Doubletree Hotel - which will expand by 78 new rooms in the project - does not currently have a labor union for its workers.

In a statement, O'Neill said that Corcoran Jennison "greatly values" all of the input the project has generated and noted that most feedback has been "overwhelmingly positive."

"In fact, the questions we hear time after time are: 'When are you really getting going on this?' 'When will it be done?' and 'How do I sign up for an apartment? We can't wait.'"

O'Neill added: "Well, the answer is: neither can we. We look forward to continuing this dialogue and process which we believe greatly benefits our project. And we want everyone to know that we look forward to hearing from them anytime they have questions or comments."