New Hampshire Superior Court Judge Richard McNamara made an encouraging decision last week regarding state-mandated chemical levels in groundwater. We hope Gov. Chris Sununu will now do whatever he can to see to it that science and sensibility, not politics, rule the day going forward.

The chemicals in question are known as PFOS and PFAS. The unsettled science about them includes the question of how much or little they affect our health and at what level (or parts per trillion).

Also up in the air is, well, what is up in the air. These chemicals can travel by air from a generating source before being deposited in groundwater. Determining the true source of generation is important both in any mitigation that may be needed and in terms of who should pay the cost.

National EPA standards for allowable minimum levels are set in the 70 ppt range. New Hampshire’s Department of Environmental Services proposed a lower limit earlier this year, in the 38 ppt range. But before the public and businesses could fully react, as the law requires, a House committee got into the act and OK’d DES levels that, at just 12 ppt, are by far the strictest in the country.

While it is sometimes good to err on the side of caution, this arbitrary ruling seems devoid of science and logic. Logic would include some form of cost-benefit analysis, i.e., will it cost each town and city in the state $5 billion to eliminate the possibility of a single case of cancer? Or 10 cases? Without answers, this is akin to stopping all carbon-based fuel uses immediately in the hope of stopping climate change, even though people will freeze and the economy will cease without fuel for transport.

Businesses and some local governments, seeing what this arbitrary decision could mean, sued DES. Judge McNamara has ruled in their favor but has delayed his order until Dec. 31, giving the state and plaintiffs time to appeal to the state Supreme Court.

While we believe that court will see the facts and uphold McNamara, we hope that Gov. Sununu will use this breather to see if some common sense can be brought to bear with DES.