Negotiations between Princeton residents, the municipality, and the Williams Company, which is proposing a 1.2-mile natural gas pipeline through the Princeton Ridge, have resulted in some recent concessions by the company regarding safety and environmental sensitivity.

Though nothing has been put in writing, Williams may possibly turn off the existing pipeline, which is within a few feet of the proposed new line, during a portion of the excavation, estimated to take about three months to complete. While that makes residents and officials worried about blasting or a possible rupture breathe a bit easier, there are still outstanding safety issues, according to a member of the citizens group focused on the issue.

“Williams initially dismissed it out of hand when we raised the issue of turning it [the existing pipeline] off,” said Barbara Blumenthal, of The Princeton Ridge Coalition. “Now, they’re saying they’ve gotten permission internally to shut it off for four to six weeks (during excavation). That’s good, but safety issues are still there. They are not even talking about turning the pipeline off during the process of laying the pipe.”

Chris Stockon, a spokesman for Williams, said the company will lower the pressure significantly while construction is taking place. “This was something important to the town, and we’re going to work to accommodate that request if we can,” he said.

Williams’ pipeline proposal is part of the $600 million Leidy Southeast expansion project. The Princeton portion of the new line would be installed near the existing line that was built in 1958. The company filed its plans with the Federal Energy Regulatory Commission (FERC) last September. Construction could begin in the spring of 2015.

Another possible concession initiated by local efforts is that Williams has been asked by FERC to explore a plan that would take the new pipeline to a location west of the route that the company is pursuing. The Princeton Ridge Coalition submitted a plan to the agency as comments on Williams’ proposal, because it did not consider the company’s plan to be viable.

“In our comments, we did a GIF (geographic information system) study of possible alternative routes, and we were able to demonstrate that there are much better routes to the west of the one they have proposed,” Ms. Blumenthal said. “We did the exercise simply to demonstrate that you can go through agricultural fields, avoiding the old forest, and find a route with significantly less environmental impact. It isn’t that we came up with a perfect solution, it’s just a baseline thing. But in response, FERC has requested that Williams take a look at these routes.”

Ms. Blumenthal also hopes that in issuing a wetlands permit to the Williams company, The New Jersey Department of Environmental Protection may ask the company to look at an alternate route. “They haven’t gotten to that point yet, but it’s one of the things that the State of New Jersey can request in order to minimize the damage to wetlands,” she said.

Mayor Liz Lempert said she is encouraged by the developments. “We’ve had many meetings with representatives from Williams throughout this year, and it’s important that we continue to have a productive dialogue with them. So far, they have shown a willingness to listen and to make changes to their plans,” she said.

Ms. Lempert praised the Princeton Ridge Coalition, while also crediting the town’s engineer Bob Kiser and his staff for work on the issue. She shares the citizens’ group’s concerns about safety. “There are certainly safety concerns, especially when it comes to construction and especially given the topography and geology of the ridge,” she said. “But the fact that they’ve agreed to shut off the pipeline during phases of construction is a huge step in the right direction. It’s going to be a long process, and there is a lot at stake.”