Gross alpha in Vermont well water
In Vermont, 6% of 12,345 private wells tested had gross alpha above the Vermont limit (15 pCi/L), according to the Vermont Department of Health.
Gross alpha is a screening test for radioactive elements in water, mainly radium and uranium from granite bedrock. A high result means one of those is present and the specific test should follow. Alpha emitters raise cancer risk when swallowed over years.
By county, from homeowner tests
Share of private wells above the state guidance level (15 pCi/L) in tests homeowners sent to the state lab, to .
| County | Wells tested | Above state level | Highest | |
|---|---|---|---|---|
| Orleans | 375 | 11% | 395 pCi/L | |
| Rutland | 879 | 11% | 281 pCi/L | |
| Chittenden | 2,624 | 9% | 2,670 pCi/L | |
| Bennington | 280 | 7% | 295 pCi/L | |
| Franklin | 1,249 | 6% | 216 pCi/L | |
| Lamoille | 890 | 5% | 146 pCi/L | |
| Addison | 1,051 | 5% | 80.7 pCi/L | |
| Washington | 1,676 | 4% | 248 pCi/L | |
| Caledonia | 463 | 4% | 72.5 pCi/L | |
| Windham | 627 | 3% | 191 pCi/L | |
| Windsor | 1,295 | 2% | 45.7 pCi/L | |
| Orange | 714 | 2% | 40.9 pCi/L | |
| Grand Isle | 201 | <1% | 23.5 pCi/L |
Towns with the highest share above the state level
- Middletown Springs, Rutland County47% of 30 wells
- Newport, Orleans County42% of 33 wells
- Richford, Franklin County39% of 36 wells
- St. George, Chittenden County36% of 62 wells
- Westmore, Orleans County35% of 40 wells
- Bakersfield, Franklin County24% of 42 wells
- Castleton, Rutland County22% of 102 wells
- Ripton, Addison County21% of 52 wells
- Hubbardton, Rutland County21% of 34 wells
- Peacham, Caledonia County19% of 47 wells
- Marshfield, Washington County18% of 38 wells
- Hinesburg, Chittenden County18% of 274 wells
- Reading, Windsor County18% of 33 wells
- Bennington, Bennington County18% of 34 wells
- Pittsford, Rutland County16% of 50 wells
- Richmond, Chittenden County15% of 255 wells
- Townshend, Windham County14% of 36 wells
- Pawlet, Rutland County14% of 52 wells
- Williston, Chittenden County12% of 223 wells
- Essex, Chittenden County11% of 203 wells
- Cabot, Washington County11% of 71 wells
- Derby, Orleans County11% of 45 wells
- Hyde Park, Lamoille County11% of 66 wells
- Cornwall, Addison County10% of 80 wells
- Enosburgh, Franklin County10% of 50 wells
Sources
- Vermont Tracking private well summaries: Town summaries of private well tests reported to the Vermont Department of Health, published through Vermont Environmental Public Health Tracking. Shares are against the limit Vermont applies to each analyte: arsenic 10 ug/L, uranium 20 ug/L (stricter than EPA), fluoride 4 mg/L, nitrate 10 mg/L, gross alpha 15 pCi/L, radon 4,000 pCi/L advisory. Only towns with 20 or more results are published; statistics below the reporting limit show as *. Retrieved September 3, 2026.