Well water · PFAS results

Your well PFAS result, explained

The letter lists results for eighteen different PFAS compounds, most of which mean nothing to anyone outside a laboratory. Two of them decide whether the state pays for a treatment system.

The short version. Look for PFOA and PFOS on your results sheet. If either is at or above 10 parts per trillion (ppt, which labs also write as ng/L), you're eligible for the state rebate: up to $5,000 toward a whole-house treatment system, or $1,000 toward a single-tap filter. The other sixteen compounds are reported for information and don't affect eligibility. You have six months from the date on the results letter to apply.

1. What the numbers mean

Parts per trillion

PFAS is measured in parts per trillion — ppt, which laboratories also write as ng/L, nanograms per litre. The two are the same thing. A part per trillion is roughly one drop of water in twenty Olympic swimming pools.

The very small units aren't a sign that the amounts are trivial. PFAS compounds don't break down in the environment and accumulate in the body over years, so the standards are set at concentrations that would be meaningless for most other contaminants. A result of 15 ppt PFOA isn't "almost nothing" — it's 50% above New York's guideline.

Non-detect, ND, and the < symbol

"ND", or a result written as <2.0, means the lab didn't find the compound above its reporting limit. It doesn't mean zero; it means below what that method could measure. The reporting limit is usually printed alongside.

Why eighteen compounds and only two thresholds

PFAS is a family of thousands of synthetic chemicals. The state programme reports eighteen of them so you have a full picture of what's in your water. Only PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonic acid) carry the 10 ppt threshold that triggers eligibility. They're the two oldest, most studied and most regulated compounds in the family.

The numbers in context. New York set maximum contaminant levels of 10 ng/L each for PFOA and PFOS in public water supplies, which is where the 10 ppt figure in the well programme comes from. The federal Environmental Protection Agency has since set its own national limits for these compounds in public water systems, at a lower figure. Neither standard legally applies to a private well — private wells are unregulated, which is exactly why the state runs a voluntary programme instead. The standards are the yardstick, not an obligation on you.

2. The questions everyone asks first

Is it safe to shower and bathe in it?

State health guidance has consistently been that the main route of exposure to PFAS from drinking water is swallowing it — drinking, cooking, making coffee, mixing formula. PFAS aren't readily absorbed through the skin and don't evaporate into the air the way solvents do, so showering, bathing, washing dishes and doing laundry aren't the concern.

Check the current wording in the guidance NYSDOH sends with the results, or call the state information line on 800-458-1158, and ask your own doctor if you have specific health concerns. Don't take a page on the internet, including this one, as the final word on a health question about your own family.

Can I boil it?

No — boiling makes it worse. It drives off water and leaves the PFAS behind, so the concentration in what's left goes up. Boiling is for bacteria. It does nothing helpful for PFAS, nitrate, arsenic or lead.

Does a Brita or other pitcher filter remove PFAS?

Not unless it's specifically certified to. This is the most common and most expensive misunderstanding in the whole subject. A standard carbon pitcher filter is designed to improve taste and odour and to reduce chlorine; that's a different job from capturing PFAS, and a filter that does one doesn't automatically do the other.

The certification to look for is NSF/ANSI 53 for PFAS reduction specifically, or NSF/ANSI 58 for reverse osmosis units. Putnam County's health department points residents to that standard. A product certified to NSF/ANSI 42 for taste and odour is not a PFAS filter, whatever the box implies. Check the certification listing for the exact model, not the brand.

A certified pitcher or under-sink filter is a reasonable stopgap while you arrange something permanent, and a reasonable permanent answer for a rental or a second home. It isn't a substitute for treating the supply if you own the house and the state is offering to pay for it.

What do I drink in the meantime?

Bottled water, or water from a certified filter, for anything you swallow — drinking, cooking, ice, coffee, pet bowls, and above all infant formula. Note that the rebate programme does not reimburse bottled water, so this is your own cost for however long the process takes.

What about my health, and my family's?

Health agencies associate long-term PFAS exposure with a range of effects that are still being researched, and the appropriate response depends on your own history and how long you've been drinking the water. That's a conversation for a doctor with your results in front of them, not a website. NYSDOH publishes plain-language information on PFAS and private wells and staffs an information line on 800-458-1158.

3. The two kinds of treatment

Both approved options are filtration. Nothing is added to your water and no chemical treatment is involved — the water passes through a medium that traps the PFAS on the way in.

	Whole-house (POET)	Single tap (POUT)
What it is	Up to two tanks of granular activated carbon, or ion exchange resin, plumbed into the main line where water enters the house	A small carbon canister under one sink, or at one tap
What it treats	Every tap, shower and appliance in the house	One tap — usually the kitchen cold
State rebate ceiling	$5,000	$1,000
Usually chosen when	The default, where there's space and accessible plumbing	A whole-house system won't fit, or the plumbing isn't accessible
Ongoing cost	Media replacement and periodic testing, yours forever	Cartridge changes, yours forever

Whole-house PFAS treatment: what the rebate covers

State rebate — up to $5,000

You pay anything above

$0$8,000

The green band is the programme's ceiling, not a quoted price. A straightforward whole-house carbon installation often lands under it, in which case the rebate covers the job in full; a difficult one doesn't. Get two or three written quotes before assuming either.

What a whole-house system includes

The programme's eligible costs for a POET installation cover considerably more than the tanks: a sediment pre-filter, a UV disinfection unit, a flow meter, a flow restrictor, sampling ports, valves and piping, the labour to install it, and the laboratory testing afterwards that confirms the system is working. That last item matters — the installation isn't finished until a certified lab has cleared it.

The third option: abandon the well

If a public water main is actually available to connect to, the programme will reimburse up to $10,000 to connect the house to it. No filter, no maintenance, no well. The work has to be done by a qualified utility contractor, and the eligible costs and connection fees are agreed with the local water authority. A pressure relief valve and a water heater expansion tank are eligible where they're needed.

Two things the treatment doesn't do. It doesn't clean the groundwater — the PFAS is still in the aquifer, and it's being filtered out on the way into your house, every day, indefinitely. And carbon fills up: the state pays to install the system and explicitly doesn't pay for operating or maintaining it afterwards. Media replacement, cartridge changes and follow-up testing are your cost, permanently. Factor that into the choice between POET and POUT, and ask any contractor quoting the job what annual maintenance actually costs before you sign.

4. What you'll actually pay

A whole-house carbon system for a typical single-family home generally lands in the low thousands installed; a certified under-sink unit is a few hundred to around a thousand. Against a $5,000 or $1,000 ceiling, a straightforward job may be covered in full — but the ceiling is a ceiling, not a grant, and anything above it is yours.

Those are indicative ranges to help you judge a quote, not prices we've collected locally. Get two or three written quotes. We'll publish quoted figures from Hudson Valley contractors here once we have them.

You don't necessarily have to front the money. The rebate is a reimbursement: normally you hire the installer, pay the bill, and the county pays you back. But the programme provides an Assignment of Payment Form that lets the rebate be paid directly to the treatment installer or contractor instead. If laying out several thousand dollars and waiting is a problem, ask about that form at the outset — both with the county and with any contractor you're considering. Not every contractor will know it exists.

What isn't covered

Bottled water while you wait
Water softeners and acid neutralisers
Pressure tanks and booster pumps
Permit fees and sales tax
Interest and late fees
Sampling for anything other than PFAS
Operation and maintenance after installation

If your well also has iron, hardness or acidity problems — and many wells in this region do — a contractor may sensibly recommend treating those at the same time. That's often the right call technically, but those components are your cost, and they should appear as separate lines on the quote so the county can see what's eligible.

5. What to do this week

Find the date on your results letter. The six-month clock starts there, not from when you get around to reading it.
Switch to bottled or certified-filtered water for anything you swallow.
Call your county's health department and confirm what the application requires and whether it's still accepting applications — counties pause at 600 testing applications. For Putnam: 845-808-1390. For other counties, start with the NYSDOH information line on 800-458-1158, which will route you to the right contact.
Get two or three quotes, and ask each contractor whether they'll accept payment by assignment.
Keep every receipt and every lab report. The county reviews the application and issues payment against documentation.

Full details of the programme, the four rebate amounts and the application process →

Get quotes for a PFAS treatment system

We're building a directory of water treatment installers and DEC-registered well contractors for Putnam and the neighbouring counties, the same way we did for septic installers. Tell us what you need and we'll pass it to registered contractors serving your town as that list comes together.

Sources and caveats

This page explains a state programme and general water treatment principles. It isn't medical advice and it isn't a substitute for the guidance issued with your own results. Programme terms change; confirm current rules with the county before spending money. We take no commission on any equipment mentioned here and we don't link to products — that's deliberate.

NYSDOH — Private Well PFAS Testing and Mitigation Rebate Pilot, programme outline (rebate limits, eligible costs, county pause mechanics): health.ny.gov › privatewellspilot › programoutline.pdf
NYSDOH — PFAS in private wells: health.ny.gov › pfasinprivatewells
Putnam County Department of Health, Environmental Health (PFAS FAQ, NSF/ANSI 53 guidance, certified laboratory list): putnamcountyny.gov/health/environmental
NYSDOH information line: 800-458-1158

Last reviewed 25 August 2026.