Plymouth Township Data Center, Plymouth Township, Pennsylvania

Developer Brian O'Neill is back before Plymouth Township's Zoning Hearing Board with a second application for a 2 million-square-foot data center in ten existing buildings at the closed Cleveland-Cliffs steel mill, on 66 acres along the Schuylkill River in Plymouth Township, Montgomery County, Pennsylvania. The Plymouth Township data center site at 900 Conshohocken Road is about a mile from downtown Conshohocken, and this is O'Neill's second application for it.

The township's planning board unanimously refused to recommend his first plan in fall 2025. At the zoning hearing board on November 17, 2025, O'Neill's attorney Edmund Campbell pulled that application after Cleveland-Cliffs' attorney Heather Fine said he had no standing because no sale had been agreed. “The signed agreement that was transmitted to my colleague at 5:51 p.m. this evening had redline changes. Those have not been accepted by my client,” Fine said.

“It is the smallest of small wins, because we're making it harder for something bad to happen to our community,” said resident Nick Liermann. “But we will be back in this room in a few months.”

The new application seeks a special exception in the Heavy Industrial district, which requires the zoning board to find the data center meets the ordinance's standards; if granted, it would still have to go through the township's land development process. O'Neill has also filed a challenge to the validity of the zoning ordinance, arguing that it unfairly fails to provide for data centers.

He estimates the data center would bring in $420 million in taxes over 20 years and 800 permanent jobs, and says he is in talks with a top-five technology company and would use on-site natural gas generators.

The first hearing on the new application, in August 2026, was repeatedly interrupted as residents booed and shouted at O'Neill's attorney and his planning witness, who testified that data centers resemble manufacturing because “Data is a raw material, which is used to manufacture a product. AI is a product.” “They just don't care. They want the money, they want the win at this point,” said Ardis Leukens, who lives about 500 feet from the site.

A petition against the data center has more than 4,000 signatures. “The direct impact on our air is my biggest concern,” Genevieve Boland, who helped lead the petition, said in 2025. “At that rate we simply can't build enough power generation to keep up, so prices will continue to rise rapidly,” said Tom Schuster, president of the Pennsylvania chapter of the Sierra Club.

O'Neill's five data center sites in neighboring Upper Merion Township were voted down by that township's supervisors in August 2026. In Plymouth the decision belongs to the Zoning Hearing Board, an independent body appointed by the township council. The hearings were set to continue in September 2026; no result has been published.