The Greenbelt City Council has joined a growing coalition that opposes cellphone towers being placed on school properties in Prince George’s County.

The council voted last week to send a letter to the county school system and County Executive Rushern L. Baker III (D) expressing their objection to the school system’s proposal to possibly construct cell towers at Eleanor Roosevelt High School, Greenbelt Middle School and Turning Point Academy.

The schools are among 70 potential sites for future cell towers.

Michael McLaughlin, Greenbelt city manager, said the city has opposed cellphone towers on city property for more than a decade and “this seemed to be a logical extension of that, with some of the health concerns that are out there but haven’t been proved conclusively.”

The vote was unanimous.

(Joel Richardson/The Washington Post)

Earlier this year, the president of the county NAACP asked the school board to stop building the towers until school officials reviewed information about possible dangers the towers could pose.

Bob Ross, head of the county NAACP, told schools chief Kevin M. Maxwell that the towers are an environmental justice issue, with questions swirling about the risks associated with an exposure to radio-frequency radiation.

More than 1,200 people have signed an online petition urging the school system to do away with its cell tower plans.

“We believe this issue needs a public airing in Prince George’s County,” the petition reads. “Residents and parents are concerned about safety issues, property value devaluation, and long-term health risks. Many community members feel they were not appropriately notified. Many parents had no idea of these plans.”

The school system voted in 2011 to enter into an agreement with Milestone Communications. The company plans to have five sites in place by next year, according to Leonard Forkas, president of Milestone.

He said there are no immediate plans to build towers in Greenbelt.

Forkas said his company has worked with many municipalities in Maryland, Virginia and Delaware and does not recall any taking the position that Greenbelt has taken.

“They are an outlier when you look at the municipalities that we deal with,” Forkas said, noting that Greenbelt officials declined to receive information from his company before making its decision.

Forkas said cellphone towers benefit public safety and schools, arguing that most 911 calls come from wireless phones and many students have access to the Internet through wireless devices.

“We believe better connectivity makes communities better,” he said.

Under the agreement with Milestone, the school system would receive $25,000 for each site and 40 percent of the gross revenue from the tower on its site. The school system estimates that the agreement could generate $2.5 million over five years.