Full contaminant data, sample history, and sourcing for Bennington County. For readers who want to go beyond the summary.
Contaminant Data — All Analytes
15 well testing events on record, covering
20 analytes.
Data spans 1953 to 2025.
Contaminant
Samples
Years
Detection Rate
Distribution LowModHigh
vs. Limit
vs. VT Avg
Radon
31
—
100%
260% of limit
↓ 42% below
Iron
270
1970
100%
17% of limit
↓ 92% below
Manganese
341
1970
100%
6% of limit
↓ 99% below
Lead
1812
—
96%
20% of limit
↓ 72% below
Arsenic
856
—
64%
10% of limit
↓ 81% below
Chloride
772
1970
100%
2% of limit
↓ 73% below
Uranium
571
—
85%
3% of limit
↓ 59% below
Fluoride
587
1970
100%
1% of limit
↓ 60% below
HFPO-DA (GenX)
municipal
18
2023–2025
0%
—
—
Nitrate
516
1970
100%
2% of limit
↓ 24% below
Nitrite
493
—
100%
2% of limit
~ typical
PFHxS
municipal
18
2023–2025
0%
—
—
PFNA
municipal
18
2023–2025
0%
—
—
PFOA
municipal
18
2023–2025
0%
—
—
PFOS
municipal
18
2023–2025
0%
—
—
Sulfate
21
1970
100%
3% of limit
↓ 47% below
pH
49
1970
100%
—
~ typical
PFBS
municipal
18
2023–2025
0%
—
—
Hardness
198
1970
100%
—
↑ 22% above
Sodium
269
1970
100%
—
↓ 60% below
Distribution shows the share of samples in each concentration band relative to the EPA Maximum Contaminant Level (MCL): Low = below half the MCL, Moderate = between half and the MCL, High = above the MCL. Analytes without an MCL (e.g. sodium, pH) show — in the limit columns. State average is based on county median values across VT.
Compare your result with Bennington County
Of the 856 arsenic tests on record for Bennington County,
36% found none, and half were below 1 µg/L.
Of the 772 chloride tests on record for Bennington County (1970),
0% found none, and half were below 5.9 mg/L.
Of the 587 fluoride tests on record for Bennington County (1970),
0% found none, and half were below 50 µg/L.
Of the 270 iron tests on record for Bennington County (1970),
0% found none, and half were below 50 µg/L.
Of the 1812 lead tests on record for Bennington County,
4% found none, and half were below 3 µg/L.
Of the 341 manganese tests on record for Bennington County (1970),
0% found none, and half were below 3 µg/L.
Of the 516 nitrate tests on record for Bennington County (1970),
0% found none, and half were below 250 µg/L.
Of the 21 sulfate tests on record for Bennington County (1970),
0% found none, and half were below 7.55 mg/L.
Of the 571 uranium tests on record for Bennington County,
15% found none, and half were below 1 µg/L.
Data Coverage & Gaps
Well-sampled analytes (15+ samples)
Radon 31 samples
Iron 270 samples
Manganese 341 samples
Lead 1812 samples
Arsenic 856 samples
Chloride 772 samples
Uranium 571 samples
Fluoride 587 samples
Nitrate 516 samples
Nitrite 493 samples
Sulfate 21 samples
pH 49 samples
Hardness 198 samples
Sodium 269 samples
No private-well PFAS data for Bennington County
We have no private well sampling data for PFAS compounds (PFOA, PFOS, PFNA, and related chemicals) in Bennington County.
PFAS testing for private wells requires a dedicated lab panel (~$300–$500). If you are near a military base, airport, or industrial site, consider testing proactively. Learn more about PFAS →
Public vs. Private Water in Bennington County
123Active public water systems
44,630Residents on public water
31%Households on private wells
Public water systems in Bennington County are regulated by the EPA and must test and report contaminant levels. Private well owners are responsible for their own testing — there is no routine monitoring of private wells by any government agency.
CDC Health Outcome Correlations
Where contaminants detected in Bennington County have established associations with specific health outcomes, we cross-reference CDC PLACES county-level prevalence data. This is a contextual signal, not a causal claim.
This report aggregates data from the following public databases:
Water Quality Portal (WQP) — groundwater sample results for Bennington County from EPA, USGS, and state agencies. Browse WQP data →
EPA Safe Drinking Water Information System (SDWIS) — public water system inventory used to estimate the share of residents on private wells. Browse SDWIS →
Census ACS 5-Year Estimates — well and cistern household counts (variable DP04_0074E) used to calculate the private-well percentage for Bennington County. Census data explorer →
USGS Aquifer Atlas — principal aquifer type underlying Bennington County, which informs which contaminants are geologically likely. USGS Aquifer Atlas →
EPA UCMR 5 (2023–2025) — PFAS occurrence data from public water systems, used as a proxy indicator for aquifer PFAS exposure. Rows marked "municipal" in the table above come from this source. About UCMR 5 →
EPA Toxics Release Inventory (TRI) — industrial facility chemical releases near Bennington County, used in contamination risk scoring. TRI Explorer →
EPA Superfund NPL — National Priorities List sites in or near Bennington County, used in contamination risk scoring. Superfund site search →
CDC PLACES — county-level health outcome prevalence (kidney disease, cancer, heart disease) correlated with detected contaminants. About CDC PLACES →
Methodology
Raw records are downloaded from the Water Quality Portal and normalized to µg/L (ppb). Records are deduplicated by sample ID and date, and certified outliers are excluded. Analyte names are mapped to EPA canonical forms. Detection rates, distribution bands, and MCL comparisons are computed from the normalized dataset.
Distribution bands use the EPA Maximum Contaminant Level as the threshold: concentrations below 50% of the MCL are classed as Low, between 50% and 100% as Moderate, and above 100% as High. For analytes without an MCL (sodium, hardness, pH), distribution is not computed.
State comparison uses the median of county median values across all counties in VT with at least one sample for that analyte.