A seller in Amherst fills out the standard New Hampshire purchase and sale disclosure, gets to the well water question, and pauses. They've read about the contamination story an hour east in Merrimack, the one involving a manufacturing plant and hundreds of properties on bottled water for years. Their house sits nowhere near Daniel Webster Highway. They check the box, move on, and assume the question doesn't really apply to them.
That assumption is wrong, and the record shows why. Amherst has its own contamination history, separate from Merrimack's, discovered the same year through the same statewide investigation. Knowing which story actually touches your property, and how to find out for certain, is the part of the disclosure form that most sellers and buyers skip past without realizing they've skipped it.
Two Sites, One Year, Different Towns
In 2016, the New Hampshire Department of Environmental Services found PFOA in groundwater near the Saint-Gobain Performance Plastics facility on Daniel Webster Highway in Merrimack. That discovery is the one most southern New Hampshire homeowners have heard about, and for good reason. It triggered a consent decree, water line extensions, point-of-entry treatment installed at hundreds of properties, and a settlement that the Attorney General's office was still finalizing pieces of as recently as March 2026, when the state, Londonderry, and Saint-Gobain reached an agreement to extend municipal water lines under the same 2018 consent decree.
What gets left out of that story is that NHDES did not stop at Merrimack. The agency's own public timeline of the investigation records that staff deployed to Amherst that same year to sample private wells after learning that a facility called Textiles Coated International, or TCI, had operated in a manner similar to Saint-Gobain. That is a second, independent source, in a different town, identified through the same statewide sweep. NHDES and the Department of Health and Human Services went on to hold public information sessions in Merrimack, Bedford, Litchfield, and Amherst during the first year of the investigation, treating all four as places where residents needed direct answers, not just the one town with the plant most people remember.
The Town of Amherst has maintained its own page on the subject for exactly this reason, pointing residents toward NHDES contacts rather than leaving them to piece the history together from news coverage of a different town.
What the Disclosure Form Is Actually Asking
New Hampshire law has required a notification about arsenic and radon in private wells on the purchase and sale agreement since an amendment to RSA 477:4-a took effect in 2015. PFAS was added as a required seller disclosure item more recently, under RSA 477:4-d. Neither statute requires a specific test result before closing. Both exist so that a buyer walks into the transaction knowing what to ask about.
The gap is between what the form requires and what most people assume it means. Here's where that assumption tends to break down.
| What sellers and buyers often assume | What's actually true |
|---|---|
| "PFAS is a Merrimack problem, not an Amherst one." | NHDES's own investigation identified an independent source, TCI, inside Amherst in the same year it found Saint-Gobain in Merrimack. |
| "I've lived here for years with no issues, so the well is fine." | PFAS, like the arsenic and radon common in this region's bedrock, has no taste, color, or odor. Years of normal use tells you nothing about what's in the water. |
| "Signing the disclosure form covers it." | The form is a notification, not a test result. It tells the buyer that testing is recommended, it doesn't confirm the well is clean. |
| "If my well tests high, the deal is dead." | A result above the state standard is a negotiation point, most often resolved with a treatment system, a price credit, or both. |
How to Find Out What NHDES Already Knows About Your Well
Because NHDES has been sampling private wells for PFAS since 2016, there's a real chance your specific parcel, or one nearby, has already been tested. The state built a public tool for exactly this question rather than making every homeowner start from zero.
- Check the NHDES PFAS Sampling Dashboard on the state's PFAS response website to see if your address or a nearby well already has results on file.
- If nothing turns up, submit a Private Well Testing Request Form through the same site. NHDES prioritizes requests by location and can't sample every well requested, but submitting costs nothing and puts your property on record.
- If you'd rather not wait on state prioritization, or you want results in time for a specific closing date, an accredited New Hampshire laboratory can run the same panel privately.
NHDES's own April 2026 testing guidance lays out what a complete panel should cover for anyone buying or selling on a private well in this part of the state: arsenic, total coliform and E. coli, chloride, copper, fluoride, hardness, iron, lead, manganese, nitrate, nitrite, pH, radon, sodium, uranium, and the four PFAS compounds with state limits, PFOA, PFOS, PFHxS, and PFNA. That's a longer list than a basic bacteria test, and it's the list because the region's bedrock and its industrial history both contribute contaminants that a simple test would miss entirely.
What a Result Actually Changes at the Table
A high reading on any single item rarely ends a deal in this market. Treatment systems for arsenic, uranium, and PFAS are well established, and the standard path is straightforward: get an itemized quote from a licensed installer, then decide whether the seller installs the system before closing, credits the buyer for it, or the parties split the difference in the final price. Buyers typically arrange and pay for the initial test as part of their inspection contingency, since they're the ones relying on the result, though sellers who test before listing can get ahead of the conversation and avoid a late-stage surprise during the most time-sensitive part of the transaction.
The fact that Saint-Gobain's obligations under its 2018 consent decree were still being enforced in March 2026, with a new agreement covering water line extensions in a neighboring town, is worth sitting with. This isn't a closed chapter from a decade ago. It's an active regulatory relationship between the state and a company whose contamination reached multiple towns. Amherst's TCI-linked contamination was identified through the same 2016 sweep, but it never became the subject of the large, multi-year consent decree that followed in Merrimack, which is exactly why so few Amherst homeowners have heard their town's own name attached to this story.
Two Questions Sellers Actually Ask
Does this mean my well is definitely affected? No. It means the accurate question is whether your specific well has been tested, not whether your town matches the one most people associate with PFAS. Plenty of Amherst wells have tested clean. The only way to know is to check the dashboard or test directly.
What if I'm on Amherst's public water rather than a private well? Public water systems are tested and reported separately under the Safe Drinking Water Act, and the testing responsibility shifts to the utility rather than the homeowner. The disclosure conversation described here applies specifically to private wells, which serve a large share of homes outside Amherst's village center.
Selling or buying in Amherst means walking into a disclosure conversation with the right history in hand, not the one that happens to be more widely known. If you're preparing to list a well-served property, or you're under contract on one and want a second set of eyes on what the results actually mean for your offer, Lawrence Home Group can walk through it with you before it becomes a late surprise. Contact Us.
