Connecticut Department of Energy & Environmental Protection

PFAS Information for Private Well Owners

The Connecticut Department of Public Health (CT DPH) is responsible for drinking water, including private wells, in Connecticut. If natural contamination is discovered within a private well, the CT DPH Private Well Program will work with the homeowner to resolve the issue. However, when contamination is present in drinking water as a result of human activity, the DEEP Remediation Division's Potable Water Program can assist with investigation of the contamination source, evaluating water testing results, and providing guidance on available water treatment alternatives.  Because all PFAS are human-made, PFAS contamination of a private well falls within the scope of the DEEP Potable Well Program.

The following information is provided as guidance for private well owners who are considering testing their drinking water for PFAS. 

Frequently Asked Questions About Private Well PFAS Testing

Should I test my drinking water for PFAS? 

PFAS testing is not generally recommended for private well owners, because of the complexity of proper sample collection and the associated cost. If, however, if your well is located near a suspected PFAS source, or you are aware of PFAS contamination in the drinking water of an adjacent property, you may wish to test your drinking water.  

How can I find a laboratory to test my water?

If you have reason to suspect that you may have PFAS in your drinking water, you can contract a certified lab to test your water.  DPH certifies labs for this purpose; the current list can be found on the Connecticut DPH’s Environmental Laboratory Certification Program’s website.  

What does testing entail? 

The laboratory will send you sampling information and a kit for sampling. The kit will include the container for collecting a drinking water sample or the "primary sample".  You may also be provided with a container of PFAS-free water and a second empty container to collect a "field blank sample."  (The field blank is a sample of PFAS-free water that is prepared by you in a manner similar to your drinking water sample.  It is used to evaluate whether PFAS may have been accidentally introduced during the sample collection process.)  The laboratory will provide very specific instructions for collecting potable water samples and preparing the field blank sample.  It is very important to carefully follow the laboratory instructions or you may accidentally introduce PFAS into your sample. 

What analysis method should I use? 

DEEP recommends using EPA Method 533 for PFAS drinking water analysis. This will insure that all compounds with an established Drinking Water Action Level (DWAL) are evaluated. (See below for more information on DWALs.)  It is recommended that you request the laboratory also send materials and instructions to collect a field blank sample. The field blank is a quality control sample used to evaluate whether PFAS detected in the primary sample may be due to improper sample collection and handling or not.

EPA Method 537.1 is also acceptable for drinking water PFAS analysis, however PFBA, a PFAS for which CT DPH has established a DWAL, is not included in the method. A laboratory kit for Method 537.1 will include containers to collect both a primary sample as well as a field blank sample. Please be aware that some labs will charge for analysis of each sample separately, but will only report results after both samples (the primary sample and the field blank) have been analyzed. Ask the laboratory before submitting samples how you will be billed.

How much does testing cost? 

The cost to analyze a drinking water sample varies by lab but is typically $300 or more per sample. Ask your laboratory whether the analytical cost includes analysis of the 'field blank' sample as the primary drinking water sample and the field blank sample may be billed as separate analyses.

How long does it take to get my results? 

Once you have submitted your sample to the lab, results will typically be reported to you within 2-3 weeks.  Reporting times can vary, however, so check with your laboratory when submitting your sample. 

What do my well sampling results mean? 

The Connecticut Department of Public Health (CT DPH) establishes drinking water Action Levels (DWALs) that are protective of public health and also feasible based upon analytical detection and treatment technology. As of June 2023, CT DPH has established drinking water Action Levels for ten PFAS. In order to understand your well sampling results, for each chemical, compare the concentration reported in your well to the Action Level in the table below.  

If your well results contain one or more of these PFAS at concentrations above the Action Level, please notify both the DEEP and the Department of Public Health (DPH) by sending an email, with a copy of your results attached to DEEP.PFAS@ct.gov and DPH.EmergingContaminants@ct.gov.

If PFAS are present but at concentrations below the Action Level, you and your family can continue to drink your well water. 

Chemical Contaminant 
Abbreviation(s)
CT Drinking Water Action Level
(DWAL)
ng/L or ppt
9-chlorohexadecafluoro-3-oxanonane-1-sulfonic acid   9Cl-PF3ONS 2
11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid  11Cl-PF3OUdS 5
Hexafluoropropylene oxide-dimer acid  HFPO-DA or "GenX" 19
Perfluorobutane sulfonic acid  PFBS 760
Perfluorobutanoic acid  PFBA1 1800
Perfluorohexane sulfonic acid  PFHxS 49
Perfluorohexanoic acid PFHxA 240
Perfluorooctane sulfonic acid PFOS 10
Perfluorooctanoic acid PFOA 16
Perfluorononanoic acid PFNA 12

1Samples analyzed using EPA Method 537.1 will not report PFBA concentrations. 

If you have questions about other PFAS detected in your water that do not have drinking water Action Levels, please contact DPH’s Environmental Health Program. 

What should I do if my well contains PFAS levels above DPH’s drinking water Action Levels? 

If your well results contain one or more of these PFAS at concentrations above the Action Level, please notify both the DEEP and the Department of Public Health (DPH) by sending an email, with a copy of your results attached to DEEP.PFAS@ct.gov and DPH.EmergingContaminants@ct.gov.

If well contamination exceeds the value shown on the Action Level list above, DEEP is authorized under CT General Statutes Section 22a-471 to take further action in addressing groundwater contamination at the site.

Until treatment can be installed, it is recommended that you use an alternative water source such as bottled water for cooking and drinking. (PFAS cannot be removed by boiling water.)  Well water can continue to be safely used for bathing purposes. 

It is recommended that you contact your veterinarian to determine whether you should offer bottled water to pets in your home. Please refer to the DPH PFAS General Information webpage for more details and additional guidance regarding pets and agricultural water uses.

What treatment options are available for removing PFAS from private drinking water wells?

Effective treatment options for reducing PFAS in well water include the use of primarily two treatment technologies: point-of-entry (POE) granular activated carbon (GAC) and point-of- use (POU) reverse osmosis (RO) water filtration systems. Treatment effectiveness depends on having the right size system and proper maintenance. Work with a professional experienced in installing water treatment filtration systems to treat PFAS to determine which system type and size is right for your residence. 

To find products certified to reduce PFOA and PFOS by the National Sanitation Foundation (NSF) please refer to: NSF Protocol P473 Drinking Water Treatment – PFOA & PFOS.  

For additional information on water treatment, please consult with DPH’s Private Well Program or a water treatment professional for options to remove PFAS.

Where can I find more information? 

The following webpages contain additional information about PFAS in drinking water:

Who can I contact if I still have questions? 

If you have confirmed PFAS contamination in your private well, questions regarding treatment options and investigation can be directed to DEEP by emailing DEEP.PFAS@ct.gov.

For health related questions, contact your local health department or the DPH Private Well Program (860-509-8401 or DPH.PrivateWellProgram@ct.gov).

Related Webpages:

 

Content last updated November 29, 2024