9. Does the aquifer that the Island gets groundwater from have PFAS in it?

Wannacomet Water Company public water supply well sampling results have been below the Maximum Contaminant Level (MCL) Massachusetts Department of Environmental Protection (MassDEP) set as safe for PFAS in drinking water, with most wells showing no PFAS. Wannacomet public water supply wells draw water from below confining units. A confining unit may help prevent PFAS from moving vertically, deeper underground where the Wannacomet public water supply well screens are located. For comparison, most private residential (domestic) wells are screened in the upper Unconfined Aquifer, thus withdrawing groundwater from above the confining unit. 

Groundwater sample results have been reported by Nantucket Memorial Airport for on-airport shallow monitoring wells and adjacent residential drinking water wells, the Town’s Wannacomet Water Company public water supply wells, and by a limited number of private residents. This data is not a complete picture of PFAS in the Island’s aquifer.  The Airport is continuing to advance its investigation through ongoing sampling and source identification activities.  The Town is developing a groundwater sampling program, and the Siasconset Water Department will test their wells by October 1, 2021. The Town sampling program is scheduled to begin in Spring 2021 and will focus on the landfill site. Once we have that information, we will better understand if PFAS impacts the groundwater aquifer.

An aquifer is underground layer of water bearing rock and/or granular materials from which water can be extracted using a well.  

A confining unit is relatively dense and contains impermeable materials, such as clay, that may prevent transport of groundwater and pollutants deeper into the subsurface.

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1. 7. Are there public drinking water standards concerning PFAS?
2. 8. Does MassDEP have a program to support private (domestic) well testing?
3. 9. Does the aquifer that the Island gets groundwater from have PFAS in it?
4. 10. Can I hook up to public water? If Yes, how?
5. 11. Are septic systems or private wastewater treatment within a Zone II aquifer wellhead protection area regulated for PFAS? If so, how?
6. 12. Who is available to perform PFAS Sampling & Testing?
7. 13. Can PFAS drinking water or soil standards be applied to leachate or co-compost?
8. 14. Are private (domestic) wells located below (downgradient of) the landfill impacted by PFAS?
9. 15. Is there a plan to collect PFAS samples from the Wastewater Treatment Facility (WWTF) and landfill site?
10. 16. Did Waste Options perform PFAS testing at the landfill in the summer of 2019?
11. 17. Even though 2019 PFAS testing was done with an imperfect method at the time (EPA 537), were the results found concerning?
12. 18. Why did it take a year for PFAS testing to be discussed by BoH and for action to be taken?
13. 19. Is there a plan to collect PFAS samples from the Wastewater Treatment Facility (WWTF) and landfill site?