Full contaminant data, sample history, and sourcing for Hocking County. For readers who want to go beyond the summary.
Contaminant Data — All Analytes
132 well testing events on record, covering
22 analytes.
Data spans 1965 to 2022.
Contaminant
Samples
Years
Detection Rate
Distribution LowModHigh
vs. Limit
vs. OH Avg
Iron
126
1973–2019
100%
277% of limit
↓ 37% below
Manganese
119
1973–2019
100%
404% of limit
↑ 129% above
Arsenic
96
1986–2019
89%
30% of limit
↑ 90% above
Chloride
129
1973–2019
91%
33% of limit
↑ 119% above
Sulfate
29
1980–2019
79%
21% of limit
↓ 52% below
Lead
100
1975–2019
79%
0% of limit
↓ 100% below
Fluoride
81
1973–2019
77%
5% of limit
↓ 51% below
HFPO-DA (GenX)
municipal
2
2024
0%
—
—
Nitrate
39
1973–2019
95%
1% of limit
↓ 79% below
Nitrite
12
1980–2019
83%
0% of limit
↓ 22% below
PFHxS
municipal
2
2024
0%
—
—
PFNA
municipal
2
2024
0%
—
—
PFOA
municipal
2
2024
0%
—
—
PFOS
municipal
2
2024
0%
—
—
Radon
1
2019
100%
52% of limit
↑ 135% above
Uranium
1
2019
100%
7% of limit
↑ 201% above
Total Coliform
1
2019
0%
—
—
Sodium
130
1973–2019
93%
—
↑ 45% above
pH
64
1973–2019
100%
—
~ typical
PFBS
municipal
2
2024
0%
—
—
Hardness
73
1973–2019
100%
—
↓ 41% below
E. coli
1
2019
0%
—
—
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 Hocking County
Of the 96 arsenic tests on record for Hocking County (1986–2019),
11% found none, and half were below 2.9 µg/L.
Of the 129 chloride tests on record for Hocking County (1973–2019),
9% found none, and half were below 22.8 mg/L.
Of the 81 fluoride tests on record for Hocking County (1973–2019),
23% found none, and half were below 130 µg/L.
Of the 126 iron tests on record for Hocking County (1973–2019),
0% found none, and half were below 832 µg/L.
Of the 100 lead tests on record for Hocking County (1975–2019),
21% found none.
Of the 119 manganese tests on record for Hocking County (1973–2019),
0% found none, and half were below 202 µg/L.
Of the 39 nitrate tests on record for Hocking County (1973–2019),
5% found none, and half were below 100 µg/L.
Of the 29 sulfate tests on record for Hocking County (1980–2019),
21% found none, and half were below 34 mg/L.
Data Coverage & Gaps
Well-sampled analytes (15+ samples)
Iron 126 samples
Manganese 119 samples
Arsenic 96 samples
Chloride 129 samples
Sulfate 29 samples
Lead 100 samples
Fluoride 81 samples
Nitrate 39 samples
Sodium 130 samples
pH 64 samples
Hardness 73 samples
Limited data (<15 samples) — interpret with caution
Nitrite 12 samples
Radon 1 sample
Uranium 1 sample
Total Coliform 1 sample
E. coli 1 sample
No private-well PFAS data for Hocking County
We have no private well sampling data for PFAS compounds (PFOA, PFOS, PFNA, and related chemicals) in Hocking 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 Hocking County
46Active public water systems
15,504Residents on public water
68%Households on private wells
Public water systems in Hocking 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 Hocking 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 Hocking 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 Hocking County. Census data explorer →
USGS Aquifer Atlas — principal aquifer type underlying Hocking 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 Hocking County, used in contamination risk scoring. TRI Explorer →
EPA Superfund NPL — National Priorities List sites in or near Hocking 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.