Full contaminant data, sample history, and sourcing for Butler County. For readers who want to go beyond the summary.
Contaminant Data — All Analytes
559 well testing events on record, covering
22 analytes.
Data spans 1963 to 2021.
Contaminant
Samples
Years
Detection Rate
Distribution LowModHigh
vs. Limit
vs. OH Avg
Manganese
319
1972–2020
81%
194% of limit
~ typical
Iron
324
1972–2020
84%
33% of limit
↓ 92% below
PFOS
municipal
28
2023–2025
4%
108% of limit
↓ 47% below
PFOA
municipal
28
2023–2025
4%
132% of limit
~ typical
Arsenic
237
1972–2020
71%
0% of limit
↓ 100% below
Nitrate
194
1972–2020
87%
18% of limit
↑ 269% above
Lead
242
1972–2020
57%
0% of limit
↓ 100% below
Chloride
350
1972–2020
100%
19% of limit
↑ 27% above
Fluoride
226
1972–2020
91%
5% of limit
↓ 51% below
HFPO-DA (GenX)
municipal
28
2023–2025
4%
57% of limit
~ typical
Nitrite
192
1973–2020
32%
1% of limit
↑ 104% above
PFHxS
municipal
28
2023–2025
11%
41% of limit
↓ 23% below
PFNA
municipal
28
2023–2025
0%
—
—
Radon
16
1999–2001
100%
8% of limit
↓ 62% below
Sulfate
224
1972–2020
100%
32% of limit
↓ 28% below
Uranium
40
1999–2020
85%
2% of limit
~ typical
Total Coliform
2
1999–2019
40%
—
~ typical
Sodium
313
1976–2020
100%
—
~ typical
pH
356
1972–2020
100%
—
~ typical
PFBS
municipal
28
2023–2025
29%
—
↓ 22% below
Hardness
348
1972–2020
100%
—
~ typical
E. coli
2
1999–2019
20%
—
~ typical
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 OH.
Compare your result with Butler County
Of the 237 arsenic tests on record for Butler County (1972–2020),
29% found none.
Of the 350 chloride tests on record for Butler County (1972–2020),
0% found none, and half were below 48 mg/L.
Of the 226 fluoride tests on record for Butler County (1972–2020),
9% found none, and half were below 200 µg/L.
Of the 324 iron tests on record for Butler County (1972–2020),
16% found none, and half were below 69.5 µg/L.
Of the 242 lead tests on record for Butler County (1972–2020),
43% found none.
Of the 319 manganese tests on record for Butler County (1972–2020),
19% found none, and half were below 51 µg/L.
Of the 194 nitrate tests on record for Butler County (1972–2020),
13% found none, and half were below 1.7 mg/L.
Of the 224 sulfate tests on record for Butler County (1972–2020),
0% found none, and half were below 79 mg/L.
Of the 40 uranium tests on record for Butler County (1999–2020),
15% found none, and half were below 0.44 µg/L.
Data Coverage & Gaps
Well-sampled analytes (15+ samples)
Manganese 319 samples
Iron 324 samples
Arsenic 237 samples
Nitrate 194 samples
Lead 242 samples
Chloride 350 samples
Fluoride 226 samples
Nitrite 192 samples
Radon 16 samples
Sulfate 224 samples
Uranium 40 samples
Sodium 313 samples
pH 356 samples
Hardness 348 samples
Limited data (<15 samples) — interpret with caution
Total Coliform 2 samples
E. coli 2 samples
No private-well PFAS data for Butler County
We have no private well sampling data for PFAS compounds (PFOA, PFOS, PFNA, and related chemicals) in Butler 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 →
CDC Health Outcome Correlations
Where contaminants detected in Butler 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 Butler 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 Butler County. Census data explorer →
USGS Aquifer Atlas — principal aquifer type underlying Butler 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 Butler County, used in contamination risk scoring. TRI Explorer →
EPA Superfund NPL — National Priorities List sites in or near Butler 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 OH with at least one sample for that analyte.