Radon is a geology problem with houses on top of it, so we group towns by what is underneath them rather than by ZIP code. In about twenty miles this county crosses three bedrock provinces, and a system designed for one of them can be the wrong system in another.
The north and west sit on the Reading Prong — uranium-bearing Precambrian granite and gneiss, thin soils, deep bedrock wells. The centre, including Flemington itself, sits on Newark Basin red shale with a large stock of post-war full basements. The south and the Delaware corridor sit on diabase and the dark, uranium-bearing Lockatong argillite, under some of the oldest stone housing in New Jersey. Pick your town for the detail that applies where you are — or just tell us what you've got and we will route it.
Highlands ridge and limestone valley
Precambrian gneiss and granite of the Reading Prong, cut by carbonate valleys. The highest-potential ground in the county, and almost all of it on private wells.
- Bethlehem Township — a rural township on the Musconetcong Mountain ridge in the northwest of the county
- Bloomsbury — a small borough at the far western edge of Hunterdon County where the Musconetcong meets the Delaware valley
- Califon — a compact borough in the South Branch valley, hemmed in by the Highlands ridges on both sides
- Glen Gardner — a small borough in the Spruce Run valley between the Musconetcong Mountain ridge and the Highlands
- Hampton — a small borough on the Musconetcong River at the Warren County line, in the limestone valley below the Highlands
- High Bridge — a hillside borough at the southern end of the Highlands, wrapped around the South Branch and the old Taylor ironworks site
- Lebanon Township — the northern corner of Hunterdon County, spread across the Musconetcong and Schooley's Mountain ridges
- Oldwick — the historic village at the centre of Tewksbury Township, in the rolling country below the Highlands ridge
- Union Township — a rural township of ridge and valley ground west of Clinton, split by Interstate 78
Newark Basin shale country
Red shale and mudstone of the Passaic Formation under Flemington and the centre of the county. Fractured rock, plenty of basements, and a mix of public water and wells.
- Alexandria Township — a large rural township in western Hunterdon, running from the Musconetcong ridge down toward the Delaware valley
- Annandale — the main village of Clinton Township, on the rail line between Spruce Run and the Route 31 corridor
- Branchburg — the Somerset County township immediately east of Hunterdon, where the North and South Branches of the Raritan meet
- Clinton — a small town on the South Branch of the Raritan at the head of Spruce Run, built around the two historic mills
- Clinton Township — a large township wrapped around Spruce Run and reaching to Round Valley, surrounding the town of Clinton on three sides
- Flemington — the county seat of Hunterdon County, a compact borough of about one square mile surrounded on all sides by Raritan Township
- Lebanon — a very small borough on Route 22 at the eastern edge of the Round Valley country, entirely surrounded by Clinton Township
- Quakertown and Pittstown — the crossroads villages at the centre of Franklin Township, in the farm country west of Flemington
- Raritan Township — the largest township by population in Hunterdon County, wrapped completely around Flemington Borough
- Readington Township — the largest municipality by area in Hunterdon County, running from Round Valley across farmland to the Somerset County line
- Whitehouse Station — the largest village in Readington Township, grown up around the rail station on the Raritan Valley Line
Diabase uplands and the Delaware corridor
Sourland-type diabase and the dark argillite of the Lockatong Formation. Stone farmhouses, open crawl spaces, and river-town cellars cut into rock.
- Delaware Township — a large rural township between the Delaware River and the Sourland country, almost entirely farmland and woodland
- East Amwell Township — a rural township running from the Flemington side south across the Sourland Mountain ridge
- Frenchtown — a riverside borough on the Delaware at the mouth of the Nishisakawick, opposite Uhlerstown in Pennsylvania
- Hillsborough — the large Somerset County township east of Hunterdon, running from the Sourland ridge down across the Millstone valley
- Holland Township — a rural township on the Delaware in the northwest corner of the county, opposite Riegelsville
- Kingwood Township — a large rural township along the Delaware between Frenchtown and Stockton, almost entirely farmland and woodland
- Lambertville — a small city on the Delaware opposite New Hope, built up the slope from the river and the canal
- Milford — a small borough on the Delaware at the mouth of the Hakihokake, in the far west of the county
- Ringoes — the historic crossroads village of East Amwell Township, at the meeting of Route 179 and Route 202 below Flemington
- Sergeantsville — the village at the centre of Delaware Township, near the state's last remaining covered bridge
- Stockton — a very small riverside borough on the Delaware between Lambertville and Frenchtown
- West Amwell Township — the southernmost township in Hunterdon County, running from the Delaware at Lambertville up onto the western end of the Sourland ridge
Hunterdon Radon Mitigation is a referral service. We are not a certified radon measurement or mitigation business, we do not test, design, or install anything, and we do not guarantee any result.