Mystic — The Stonington Planning and Zoning Commission on Tuesday night unanimously rejected a proposal by a Southport developer to modify a previous approval to develop the former Mystic Color Lab property into 55 luxury condominiums.

The board’s 5-0 denial came after it held a public hearing on an application by Edgewood Mac LLC for a master plan zone change and site plan approval to construct four buildings around an interior courtyard with a swimming pool and cabana. The firm has said it sought the changes to create a more attractive and marketable project, one it said would generate $360,000 in annual tax revenues for the town.

A group of neighbors had opposed the Lighthouse Landing plan during the hearing.

Town Planner Keith Brynes said commission members cited the size and mass of the plan as well as their desire to maintain the character of the mill in the new plan as reasons for their opposition.

While the original plan called for incorporating the mill’s western wall and tower, the only parts not yet torn down, the new plan had called for tearing them down because the firm said it was not structurally feasible to retain them. The project originally was approved under the town’s Industrial Heritage Reuse District, designed to encourage the rehabilitation of old mill buildings. In the case of the new Edgewood Mac plan, none of the old mill would have remained.

The commission rejected the plan even though Brynes in his staff report had said that the proposed “changes to the architecture give a more residential appearance to the buildings.”

“They preferred the layout of the previous approval,” Brynes said Wednesday.

Edgewood Mac still could proceed with developing the site under the original 2005 approval and a subsequent modification from 2008. It also could appeal the denial to Superior Court or present a new plan. Brynes said the commission also invited Edgewood Mac to return and discuss the design options at a future meeting.

Pawcatuck attorney Ted Ladwig, who represented Edgewood Mac, said Wednesday that he was “surprised and disappointed” by the commission’s unanimous denial.

But he added he was optimistic about comments made by commission member John Prue on Tuesday night. Prue said the town wants something good to go on the site.

“My client would say exactly the same thing,” he said. “The job going forward is to work together and come to an agreement on what would be good for that site going forward.”

He pointed out that Edgewood Mac is committed to the site, having already purchased it and spent money on development plans.

In his staff report, Brynes had written that many of the key elements of the approved 2005 plan remained unchanged in the new application.

The buildings in the rejected proposal were 49 feet tall, 1 foot lower than the already approved plan. The gross floor area also would have been reduced from 177,373 square feet to 162,482 square feet.

After receiving approvals for the original project in 2005, the previous owners of the property tore down much of the building and began an environmental cleanup and site work before the project ceased because of financial problems. Edgewood Mac acquired the mortgage to the 5.5-acre site in 2009.

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