The Princeton Ridge Coalition has made progress in its negotiations with the Williams/Transco Corporation, which is planning to install a natural gas pipeline across the environmentally sensitive Princeton Ridge. But the citizens group still has serious issues with the safety of the company’s construction plans, which were recently filed with the Federal Energy Regulatory Commission (FERC). Williams/Transco hopes to have approval of those plans by the fall.

To address their concerns, the Coalition will hold a safety briefing detailing the company’s plans on Wednesday, June 4 at 7 p.m. in Monument Hall. Mayor Liz Lempert and municipal engineer Bob Kiser are scheduled to attend. The meeting will focus on the latest construction plans filed this month by Williams, identifying “serious risks that we believe have not been adequately addressed and present conditions that we are requesting FERC to enforce if the project is approved,” said Rakesh Joshi, a member of the group’s safety committee, in a press release.

Williams/Transco first announced in January 2013 that it planned to build a second, larger, high-pressure pipeline next to one that was installed in 1958. Since the Princeton Ridge is a combination of wetlands and hard basalt bedrock and boulders, the Coalition is especially concerned about the fact that construction activity would take place 20 feet or less from the existing line, which the company plans to leave operational during the project. In addition to the more than 150 homes located within 2,000 feet of the pipeline, it passes through the property of Stuart Country Day School. Princeton Day School is 2,000 feet away and Princeton Academy is 4,000 feet away.

According to Rob Goldston, former director of the Princeton Plasma Physics Lab and chair of the safety committee, an accident could be catastrophic. “If the old pipeline ruptures and ignites, adults and children within 2000 feet of the blast will have 90 seconds to get to shelter before developing third degree burns,” he said. “According to the Gas Research Institute, those having 30 seconds of exposure at 550 feet have a 50 percent probability of mortality.”

Coalition members have additional concerns about the company contracted to do the work, Henkels & McCoy. That firm was working at the South Fork townhouse complex in Ewing Township last March when a gas explosion killed one resident and damaged more than 50 homes. The Mercer County Prosecutor’s Office is investigating the accident, since some reports have stated that when employees of the company smelled gas, they did not evacuate residents or call 911.

Mr. Goldston said there is particular worry about Williams/Transco’s plan to leave gas on during a portion of the excavation work. The company responded to the Coalition’s requests to turn off the gas in the existing pipeline at one point in the project, but plan to have the gas on as a 60-ton “side-boom” lays new pipeline while operating on top of the old pipeline. “We are concerned that forces due to the operation of this equipment could cause a catastrophic rupture of the existing pipeline,” Mr. Goldston said. “The soil in the Princeton Ridge is saturated with water and large, hard basalt boulders ‘float’ in this soil above the bedrock. Boulders could easily be wedged between the bedrock and the pipeline and/or the pipeline and the heavy equipment, resulting in unsafe stresses.”

Barbara Blumenthal, president of the Coalition, said that although members have been encouraged by Williams/Transco’s willingness to listen to their concerns over the past year, there are lingering worries. “We are holding the safety briefing because many residents remain unaware of the risks. In the next few months, our community has an opportunity to influence this project. By the time construction begins in April 2015, it will be months too late to speak up,” she said.