Nantucket water management focuses on PFAS treatment and groundwater source expansion

During a recent meeting of the Nantucket Planning & Economic Development Commission, significant discussions centered around the island's groundwater resources and the ongoing challenges posed by PFAS contamination. The meeting highlighted the complexities of Nantucket's aquifer system, which consists of three distinct layers: the upper, middle, and lower aquifers. The upper aquifer, extending from the surface to about 75-85 feet, is separated from the middle aquifer by a semi-confining layer that restricts water flow. The middle aquifer, where most of Nantucket's water supply wells are located, is crucial for the island's drinking water.

Concerns were raised about the contamination of Well 15, which has recorded PFAS levels exceeding regulatory limits. As a precaution, this well has been offline for two years, and efforts are underway to construct a PFAS treatment system to ensure safe drinking water. The treatment system is expected to be operational before the peak tourist season, allowing for the potential use of Well 15 while also preparing Well 12, which has not shown any contamination, for future needs.

The discussions also touched on the regulatory framework governing Nantucket's groundwater. The Massachusetts Department of Environmental Protection (DEP) controls water withdrawal permits, which dictate how much water can be pumped from the aquifers. Currently, Nantucket's water withdrawal limits are based on population estimates, which fluctuate significantly between winter and summer. The town is actively working to negotiate an increase in these limits to accommodate the growing demand for water, particularly in light of PFAS contamination issues.

Additionally, the commission noted the ongoing efforts to develop a new well at North Pasture, a project that has been in the works for three years and is nearing the permitting stage. This new source of water is expected to bolster Nantucket's water supply as the island continues to address both contamination and increasing population pressures.

Overall, the meeting underscored the critical importance of managing Nantucket's groundwater resources effectively, particularly as the island faces environmental challenges and a rising population. The proactive measures being taken to address PFAS contamination and expand water supply sources reflect the community's commitment to ensuring safe and reliable drinking water for residents and visitors alike.