PSNH officials are prepared to move forward with their mercury scrubber project at its Bow plant, while the state’s Public Utilities Commission hears arguments on the subject.

On Sept. 19, the PUC gave a go-ahead to the project, which is designed to lower emissions of mercury and sulfur by 2013.

The state Legislature mandated in 2006 that PSNH install the wet scrubber to cut down on harmful emissions by 2013, but the high price tag had the New Hampshire Public Utilities Commission – the authoritative force in such endeavors – debating whether it was in the public’s best interest.

After the commission investigated its authority in superseding the Legislature’s decision, they found it was above their call to do so.

TransCanada Hydro Northeaster Inc. and three commercial ratepayers have submitted paperwork asking the commission to hold a rehearing on the topic.

“(The PUC) suspended the order pending further reconsideration,” said Martin Murray, a PSNH spokesman. “What that really did is provide the commission with more time to formally decide to grant the motions or deny them. In the meantime, nothing changes from PSNH’s perspective concerning our schedule.”

Murray said PSNH will continue to install the scrubber, which is scheduled to begin with early preparation work in November.

“The next step is up to the commission. In the meantime, nothing changes regarding our schedule,” said Murray. “We’re still moving ahead, and have to move ahead. It’s kind of a unique circumstance.”

While the deadline to have the system installed is July 1, 2013, Murray said PSNH is on schedule to finish it about a year before the deadline.

“There are incentives for the company to have the system in place earlier in order to further reduce customer costs,” said Murray.

The PUC had 10 days after the last day for petitions could be filed, which was Oct. 24, to decide whether to hold new hearings. If the PUC makes the decision to rehear the groups’ arguments, it may not change PSNH’s plans.

“They would then set a schedule that would open up a process that could be rather lengthy, but it’s not clear that our work would halt during that process because we do have a law in place that requires us to do the work,” said Murray. “The order they would be rehearing isn’t an order regarding stopping or starting the project, it focuses on whether the commission has the authority to halt the project.”

The benefit of having the plant in Bow is lowering prices for PSNH customers, said Murray.

“It’s an economic plant, a reliable plant, and while it meets all current emissions regulations, with the operation of a scrubber, it will be one of the cleanest plants in all of the New England,” said Murray. “If we can keep this plant running economically, it’s a real win for the state.”