We are a referral service, not a laboratory and not a contractor. Nothing on this site is a measurement of your property. What we do publish is other people's measurements and other people's rules, and the least we can do is say exactly whose.
The measured record
New Jersey Department of Environmental Protection, Radon Section — 2015 Radon Tier Assignment Report (May 2015). Every town page on this site shows how many test results NJDEP holds for that municipality, how many were at or above 4.0 pCi/L, and the tier that follows. Those figures are transcribed from this one document and nowhere else.
NJDEP's own tier definitions, quoted:
| Tier | Meaning |
|---|---|
| Tier 1 | High potential — at least 25 homes tested with 25 percent or more at or above 4 pCi/L |
| Tier 2 | Moderate potential — at least 25 homes tested with 5 to 24 percent at or above 4 pCi/L |
| Tier 3 | Low potential — at least 25 homes tested with fewer than 5 percent at or above 4 pCi/L |
NJDEP's figure is a cumulative count of test results in its dataset, not a count of distinct homes. The report also notes that once a municipality is designated Tier 1, NJDEP does not lower the tier even if the percentage later falls below 25 — because the radon-resistant construction required in Tier 1 areas itself lowers measured levels, and letting the designation oscillate would switch the building requirement on and off.
25 of Hunterdon County's 26 municipalities are Tier 1. The single exception is Union Township at 14%, which NJDEP places in Tier 2. We say 25-of-26 rather than "all of them" on this site for that reason, and the counts are computed from the table rather than typed, so they cannot drift.
Who is allowed to do this work
N.J.A.C. 7:28-27 — Certification of Radon Testers and Mitigators. Testing for radon or installing mitigation for a fee in New Jersey requires certification by NJDEP. Measurement and mitigation are certified separately, which is why we check them separately and route accordingly. The programme, and the register of certified businesses, is at NJDEP's radon pages.
New construction
N.J.A.C. 5:23-10 — the Radon Hazard Subcode. Radon-resistant construction techniques are required in new buildings in Use Groups R and E — residential and educational — in municipalities NJDEP designates Tier 1. See our guide to what that means here.
Bedrock geology
New Jersey Geological and Water Survey bedrock geologic mapping. The three ground profiles this site organises towns by — Highlands, Newark Basin, diabase and Lockatong — follow published bedrock mapping. Boundaries run through municipalities rather than around them, so for any specific address the NJGWS mapping is the authority and our description is only the shape of the ground.
Water from a private well
The New Jersey Private Well Testing Act. A home served by a private well must have its water tested when it is sold or leased, and gross alpha — a screen that can indicate radon and other radioactivity — is a required parameter for Hunterdon County wells. Details at NJDEP's Private Wells programme.
The action level itself
US Environmental Protection Agency. 4.0 pCi/L is the EPA and NJDEP action level; NJDEP additionally suggests considering mitigation between 2 and 4. EPA's homeowner guidance is at epa.gov/radon.
What we deliberately do not publish
- A reading for any identifiable property. Not yours, not a street, not a development. Tier classifications and geology describe an area; only a test describes a building.
- A share of homes on private wells in any town. We have no per-municipality source for it, so our town pages say which supplies occur and what a well there would be drawing from — not what proportion of addresses have one.
- A quote. Every price on this site is a typical local range, flagged as one.
Found something here that looks wrong? Tell us at contact@hunterdonradonmitigation.com and we will check it against the source and correct it. That is a genuine offer, not a formality — a page that misstates a public record is worse than no page.