Full contaminant data, sample history, and sourcing for Glynn County. For readers who want to go beyond the summary.
Contaminant Data — All Analytes
16144 well testing events on record, covering
25 analytes.
Data spans 1941 to 2025.
Contaminant
Samples
Years
Detection Rate
Distribution LowModHigh
vs. Limit
vs. GA Avg
Chloride
16136
1941–2023
100%
82% of limit
↑ 4291% above
Sulfate
674
1941–2019
100%
65% of limit
↑ 3096% above
Radon
3
2019
100%
56% of limit
↑ 206% above
Arsenic
49
1970–2019
41%
65% of limit
↑ 994% above
Iron
93
1963–2019
75%
13% of limit
↓ 67% below
Manganese
88
1967–2019
51%
2% of limit
↓ 96% below
Nitrate
572
1941–2019
47%
0% of limit
↓ 98% below
Lead
86
1967–2019
8%
0% of limit
↓ 100% below
Uranium
40
2005–2019
2%
0% of limit
↓ 44% below
PFOS
municipal
12
2024
0%
—
—
Uranium
40
2005–2019
2%
0% of limit
↓ 44% below
PFOS
municipal
12
2024
0%
—
—
PFOA
municipal
12
2024
0%
—
—
PFNA
municipal
12
2024
0%
—
—
PFHxS
municipal
12
2024
0%
—
—
Nitrite
164
1970–2019
8%
1% of limit
~ typical
Lead
86
1967–2019
8%
0% of limit
↓ 100% below
HFPO-DA (GenX)
municipal
12
2024
0%
—
—
Fluoride
282
1941–2019
99%
16% of limit
↑ 215% above
E. coli
3
2019
0%
—
—
Hardness
3301
1941–2019
100%
—
↑ 254% above
PFBS
municipal
12
2024
0%
—
—
pH
364
1951–2019
100%
—
~ typical
Sodium
279
1941–2019
100%
—
↑ 508% above
Total Coliform
3
1986–2019
50%
—
~ 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 GA.
Compare your result with Glynn County
Of the 49 arsenic tests on record for Glynn County (1970–2019),
59% found none.
Of the 16136 chloride tests on record for Glynn County (1941–2023),
0% found none, and half were below 205 mg/L.
Of the 282 fluoride tests on record for Glynn County (1941–2019),
1% found none, and half were below 605 µg/L.
Of the 93 iron tests on record for Glynn County (1963–2019),
25% found none, and half were below 30 µg/L.
Of the 86 lead tests on record for Glynn County (1967–2019),
92% found none.
Of the 88 manganese tests on record for Glynn County (1967–2019),
49% found none.
Of the 572 nitrate tests on record for Glynn County (1941–2019),
53% found none.
Of the 674 sulfate tests on record for Glynn County (1941–2019),
0% found none, and half were below 162 mg/L.
Of the 40 uranium tests on record for Glynn County (2005–2019),
98% found none.
Data Coverage & Gaps
Well-sampled analytes (15+ samples)
Chloride 16136 samples
Sulfate 674 samples
Arsenic 49 samples
Iron 93 samples
Manganese 88 samples
Nitrate 572 samples
Lead 86 samples
Uranium 40 samples
Uranium 40 samples
Nitrite 164 samples
Lead 86 samples
Fluoride 282 samples
Hardness 3301 samples
pH 364 samples
Sodium 279 samples
Limited data (<15 samples) — interpret with caution
Radon 3 samples
E. coli 3 samples
Total Coliform 3 samples
No private-well PFAS data for Glynn County
We have no private well sampling data for PFAS compounds (PFOA, PFOS, PFNA, and related chemicals) in Glynn 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 Glynn County
63Active public water systems
91,539Residents on public water
11%Households on private wells
Public water systems in Glynn 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 Glynn 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 Glynn 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 Glynn County. Census data explorer →
USGS Aquifer Atlas — principal aquifer type underlying Glynn 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 Glynn County, used in contamination risk scoring. TRI Explorer →
EPA Superfund NPL — National Priorities List sites in or near Glynn 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 GA with at least one sample for that analyte.