Concerns about cellular radiation — either real or perceived — have prompted several Katama residents to protest a plan by AT&T to place a cell antenna in an abandoned silo on town-owned property at the Farm Institute.

The plan has been in the works for well over a year. About 20 people continued to voice their objections during about two hours of discussion at Tuesday’s Edgartown planning board meeting, saying that concerns about cellular radiation would affect home values and might also affect the Farm Institute by deterring parents from sending their children to the farm’s summer camp, lowering donations and hurting sales of Farm Institute produce and meat.

In the fall of 2011, voters at a special town meeting approved installing wireless cell antennae inside the abandoned silos to improve cell phone coverage in Katama, the Edgartown harbor and parts of Chappaquiddick. AT&T responded to a request for proposals from the town.

Last May, there was a brief conflict over the tower when Farm Institute board members briefly said they opposed the cell tower location, later recanting.

But the issue continues to bother residents, including Thomas Burke, a longtime Katama resident and an abutter to the Farm Institute. The institute leases the town-owned Katama Farm for its operation as a nonprofit, educational working farm.

Mr. Burke told the planning board Tuesday that he was concerned about the potential impact on $77.5 million in assessed property in the area.

“I’m absolutely convinced . . . there will be an impact on property values,” he said, noting that a five per cent drop in property values could lead to a $27,000 drop in annual tax revenue for the town.

David Maxson, the planning board’s advisor on the issue, said the Telecommunications Act of 1996 dictates that as long as the antenna is compliant with FCC standards, the board cannot oppose the tower based on concerns about radiation.

“The Farm Institute is in the business of running an organic farm, primarily for the education of children,” institute board member Howard Miller said at the meeting in response to neighbors’ concerns. “We are the tenant of the town, and with that in mind, we felt it necessary to cooperate with the town,” he added, noting that the board “willingly” gave approval to the project,

“If we thought there was any health danger at all to our children or our animals we would not be giving our approval,” Mr. Miller said.

Planning board member Alan Wilson said when it comes to property values, people are also reluctant to rent homes that do not have cell coverage, recalling one emergency room doctor who stopped renting a home on Chappaquiddick because he did not receive service.

Planning board member Michael McCourt said he “would like to see AT&T explore the possibility of other alternatives just from a perception standpoint,” like a distributed antenna system (DAS) or another location.

But AT&T representative Dan Bilezikian said the company does not consider DAS a viable alternative, nor are there other options for the antenna location.

“We’ve eliminated every possibility,” he said. “The only other potential possible site would be the [town] water tanks, which according to the bylaw are not even on the table.” He said AT&T could bring in experts to say there will be no effect on property values, noting other antennas in Edgartown as an example.

Residents requested that the board delay a decision until the summer. In the end the board voted to continue the issue to its Feb. 5 meeting.

“Come with something new,” board chairman Robert Cavallo told the neighbors. “We’re happy to listen.”