Full contaminant data, sample history, and sourcing for Licking County. For readers who want to go beyond the summary.
Contaminant Data — All Analytes
281 well testing events on record, covering
19 analytes.
Data spans 1964 to 2024.
Contaminant
Samples
Years
Detection Rate
Distribution LowModHigh
vs. Limit
vs. OH Avg
Iron
259
1973–2014
100%
500% of limit
~ typical
Manganese
251
1973–2014
98%
213% of limit
↑ 21% above
Arsenic
228
1977–2014
96%
57% of limit
↑ 262% above
Sulfate
84
1982–2014
98%
32% of limit
↓ 27% below
Chloride
263
1973–2014
98%
9% of limit
↓ 39% below
Fluoride
204
1973–2014
83%
16% of limit
↑ 61% above
HFPO-DA (GenX)
municipal
15
2023–2025
0%
—
—
Lead
226
1975–2014
65%
0% of limit
↓ 100% below
Nitrate
42
1973–2013
33%
0% of limit
↓ 100% below
Nitrite
48
1991–2013
40%
0% of limit
↓ 100% below
PFHxS
municipal
15
2023–2025
0%
—
—
PFNA
municipal
15
2023–2025
0%
—
—
PFOA
municipal
15
2023–2025
0%
—
—
PFOS
municipal
15
2023–2025
0%
—
—
Uranium
9
2012
89%
12% of limit
↑ 425% above
Hardness
213
1973–2014
100%
—
~ typical
PFBS
municipal
15
2023–2025
0%
—
—
pH
174
1973–2013
100%
—
~ typical
Sodium
262
1973–2014
100%
—
~ 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 Licking County
Of the 228 arsenic tests on record for Licking County (1977–2014),
4% found none, and half were below 5.7 µg/L.
Of the 263 chloride tests on record for Licking County (1973–2014),
2% found none, and half were below 22 mg/L.
Of the 204 fluoride tests on record for Licking County (1973–2014),
17% found none, and half were below 435 µg/L.
Of the 259 iron tests on record for Licking County (1973–2014),
0% found none, and half were below 1.5 mg/L.
Of the 226 lead tests on record for Licking County (1975–2014),
35% found none.
Of the 251 manganese tests on record for Licking County (1973–2014),
2% found none, and half were below 105 µg/L.
Of the 42 nitrate tests on record for Licking County (1973–2013),
67% found none.
Of the 84 sulfate tests on record for Licking County (1982–2014),
2% found none, and half were below 78.7 mg/L.
Data Coverage & Gaps
Well-sampled analytes (15+ samples)
Iron 259 samples
Manganese 251 samples
Arsenic 228 samples
Sulfate 84 samples
Chloride 263 samples
Fluoride 204 samples
Lead 226 samples
Nitrate 42 samples
Nitrite 48 samples
Hardness 213 samples
pH 174 samples
Sodium 262 samples
Limited data (<15 samples) — interpret with caution
Uranium 9 samples
No private-well PFAS data for Licking County
We have no private well sampling data for PFAS compounds (PFOA, PFOS, PFNA, and related chemicals) in Licking 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 Licking County
86Active public water systems
128,940Residents on public water
41%Households on private wells
Public water systems in Licking 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 Licking 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 Licking 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 Licking County. Census data explorer →
USGS Aquifer Atlas — principal aquifer type underlying Licking 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 Licking County, used in contamination risk scoring. TRI Explorer →
EPA Superfund NPL — National Priorities List sites in or near Licking 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.