PFAS in private wells: should you test and where

Yes, PFAS testing can be a smart extra well test if your home is near a known contamination area, if agencies are sampling nearby, or if you simply want a clear answer from a certified lab. Not every private well owner in every state is told to test right away, but private wells are not routinely monitored like public water systems, so the choice often falls to the homeowner. (cdc.gov)

Why PFAS get so much attention

PFAS are a large family of human-made chemicals used in products that resist water, grease, stains, and heat. They break down very slowly, can stay in the environment for a long time, and some can build up in the body over time. About 1 in 8 people in the United States get drinking water from a private well, and private drinking water sources are not covered by the federal Safe Drinking Water Act. (atsdr.cdc.gov)

Scientists are still learning about PFAS, but health agencies say studies have linked exposure to some PFAS with higher cholesterol, reduced antibody response to some vaccines, small decreases in birth weight, pregnancy-related high blood pressure, changes in liver enzymes, and, for PFOA, increased risk of kidney and testicular cancer. That does not mean every exposure will cause illness, but it does explain why many well owners want a lab result instead of a guess. (atsdr.cdc.gov)

Should you test your private well for PFAS?

For every well owner, EPA recommends a basic annual check for total coliform bacteria, nitrates, total dissolved solids, and pH. PFAS is not on that basic yearly list. Instead, EPA says to test for other contaminants when there are known groundwater or drinking water problems in your area, when conditions near the well change, or when new industrial activity is nearby. (epa.gov)

That means PFAS testing is usually a targeted add-on, not an automatic yearly test for everyone. Minnesota, for example, says it does not recommend that every private well be tested for PFAS, but it does point homeowners to testing if they are in or near a known contamination investigation. Pennsylvania’s health department says private wells can be contaminated by PFAS from sources such as airports or properties where PFAS firefighting foam was used, landfills, farmland that historically received municipal waste or biosolids, and leaking septic tanks. (health.state.mn.us)

A practical checklist:

• Test sooner if a state, local, or federal agency has sent a notice about PFAS, groundwater contamination, or a nearby investigation.
• Move PFAS higher on your list if you live near a likely source area, such as a site tied to firefighting foam use, a landfill, or land where certain wastes were historically applied.
• Consider testing before you spend money on treatment, so you know whether PFAS is actually present and which compounds the lab found.
• Keep routine well testing going too, because PFAS is only one part of private well safety. For the bigger picture, use the Well water test planner. (health.state.mn.us)

Where to get a PFAS test

The safest place to start is a state-certified drinking water laboratory. EPA says homeowners should contact their state laboratory certification program to find out whether the state has certified laboratories for PFAS analysis or has other recommendations while state PFAS certification programs are being set up. EPA also says Methods 533 and 537.1 are the approved drinking water methods most homeowners will hear about, and together they can measure 29 PFAS in drinking water. (epa.gov)

If you need help finding a lab, start with the site’s state-by-state directory, then read How to choose a state-certified drinking water lab. Minnesota also tells homeowners to contact the lab directly to ask about required samples, sample collection, and shipping. (health.state.mn.us)

Ask these questions before you order anything:

1. Do you accept samples from private homeowners for PFAS?
2. Which PFAS method or panel do you use, and which compounds are included?
3. Will you send the bottles, forms, and instructions I need?
4. How should I handle sampling if I already have a filter or treatment system?
5. How long does the lab keep the sample valid during shipping? (epa.gov)

In some places, official investigation programs may contact nearby residents and arrange testing directly. Pennsylvania notes that homes in certain investigation areas may be contacted by state or federal agencies or their contractors for sampling, and it also notes that limited free private well testing may be available through some programs. Because PFAS rules, lab approval, and follow-up steps vary by state, confirm the current process with your state health department, environmental agency, or lab certification program. (pa.gov)

How to collect the sample without ruining the test

PFAS sampling is not the time to wing it. Minnesota advises homeowners to work directly with the lab on the number of samples, how to collect them, and how to ship them. In plain terms, that means you should wait for the lab’s kit and instructions, read them carefully, and follow them exactly. (health.state.mn.us)

If you are deciding between a kitchen tap sample and a sample taken before treatment, ask the lab which one matches your goal. Some homeowners want to know what is coming from the well itself. Others want to know what people are actually drinking at the tap. If you want a refresher on avoiding common sample mistakes, see How to collect a well water sample without ruining the test and Home water test kits vs. certified lab tests. (health.state.mn.us)

What the results mean

Your report should list each PFAS the lab tested for and the concentration found. EPA says water test reports may compare results with national drinking water standards, while states may also use their own health-based guidance values. That can make PFAS reports feel harder to read than a simple bacteria or nitrate result. (epa.gov)

The big thing to remember is that public-water rules and private-well decisions are not exactly the same process. EPA’s drinking water compliance framework is built around public water systems, while private well owners usually need state or local guidance on what a result means, whether a second sample is needed, and what kind of follow-up makes sense. Minnesota, for example, publishes health-based guidance values for several PFAS and offers help interpreting private well results. (epa.gov)

Keep the full report, not just the summary page. Save the method name, the list of PFAS tested, the date, and the units. Those details matter if you ever compare one result with another, talk with a health official, or shop for treatment. For help with the format and terms on a lab report, see How to read a water test report: MCLs, units and flags. (epa.gov)

What to do if PFAS is found

Start with interpretation. Ask your state or local health office, or the well program named by your state, whether the result calls for a repeat sample, a treatment discussion, or an alternate drinking water source. Pennsylvania advises that if PFAS levels are high, untreated well water should not be used for drinking, cooking, food preparation, making infant formula, or brushing teeth. (pa.gov)

For treatment, the main options mentioned by health and environmental agencies are reverse osmosis, granular activated carbon, and ion exchange. Pennsylvania notes that a point-of-use system at one tap may be enough when the main concern is swallowing water, while a whole-home point-of-entry system is another option for broader treatment. (pa.gov)

Whatever system you consider, EPA says to look for certification for PFAS reduction under NSF/ANSI 53 or NSF/ANSI 58. EPA also warns that, as of April 2024, current PFAS filter certifications do not yet show that a filter will remove PFAS all the way down to EPA’s newest drinking water standard, so certification is helpful but not the whole story. Maintenance matters too: a filter that is not replaced on schedule can stop working as intended. (epa.gov)

Frequently asked questions

Do all private wells need a PFAS test every year?

No. EPA’s basic annual private well check is for total coliform bacteria, nitrates, total dissolved solids, and pH. PFAS testing is usually added when there is a known local concern, a nearby investigation, or a homeowner wants a specific PFAS answer from a lab. Minnesota is one example of a state that does not recommend PFAS testing for every private well. (epa.gov)

Is a home test kit enough for PFAS?

For PFAS, a state-certified lab is the better choice. EPA points homeowners to state laboratory certification programs, and Minnesota tells homeowners to work directly with the lab on sample collection and shipping. PFAS testing is method-specific, so you want a lab that can explain exactly what it is testing for. (epa.gov)

What if my report uses state guidance instead of a federal number?

That is common. Private well follow-up often depends on state health-based values, agency practice, and the exact PFAS found. Use the report as a starting point, then confirm the interpretation with the official office that handles private wells or PFAS in your state. (health.state.mn.us)

If PFAS is found, do I need a whole-house filter?

Not always. If the main concern is water people swallow, Pennsylvania says a point-of-use system at a kitchen faucet may be enough. Whole-home systems are also available, but the right choice depends on the compounds found, the levels, and your household’s needs. (pa.gov)