Data & Methodology — Marinette County

Full contaminant data, sample history, and sourcing for Marinette County. For readers who want to go beyond the summary.

Contaminant Data — All Analytes

82 well testing events on record, covering 20 analytes. Data spans 1905 to 2022.

Contaminant Samples Years Detection Rate Distribution LowModHigh vs. Limit vs. WI Avg
Iron 65 1905–2015 92%
65% of limit ↓ 73% below
Manganese 63 1950–2015 89%
61% of limit ↓ 55% below
Arsenic 20 1976–2015 85%
27% of limit ↑ 75% above
Sulfate 65 1905–2015 100%
12% of limit ↑ 64% above
Chloride 66 1905–2015 100%
4% of limit ~ typical
Fluoride 65 1950–2015 94%
8% of limit ↑ 59% above
HFPO-DA (GenX) municipal 20 2022–2025 0%
— —
Lead 20 1976–2015 25%
0% of limit ↓ 62% below
Nitrate 61 1960–2015 66%
1% of limit ↓ 95% below
Nitrite 43 1961–2015 42%
0% of limit ↓ 54% below
PFHxS municipal 20 2022–2025 0%
— —
PFNA municipal 20 2022–2025 0%
— —
PFOA municipal 20 2022–2025 10%
4% of limit ↓ 75% below
PFOS municipal 20 2022–2025 0%
— —
Radon 5 1995–2003 100%
9% of limit ↓ 46% below
Uranium 8 2002–2015 100%
1% of limit ↓ 66% below
Hardness 67 1905–2015 100%
— ~ typical
PFBS municipal 20 2022–2025 0%
— —
pH 69 1950–2015 100%
— ~ typical
Sodium 61 1905–2015 100%
— ↑ 45% above

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 WI.

Compare your result with Marinette County

Of the 20 arsenic tests on record for Marinette County (1976–2015), 15% found none, and half were below 2.1 µg/L.

Of the 66 chloride tests on record for Marinette County (1905–2015), 0% found none, and half were below 10.8 mg/L.

Of the 65 fluoride tests on record for Marinette County (1950–2015), 6% found none, and half were below 200 µg/L.

Of the 65 iron tests on record for Marinette County (1905–2015), 8% found none, and half were below 130 µg/L.

Of the 20 lead tests on record for Marinette County (1976–2015), 75% found none.

Of the 63 manganese tests on record for Marinette County (1950–2015), 11% found none, and half were below 30 µg/L.

Of the 61 nitrate tests on record for Marinette County (1960–2015), 34% found none, and half were below 10 µg/L.

Of the 65 sulfate tests on record for Marinette County (1905–2015), 0% found none, and half were below 29 mg/L.

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Data Coverage & Gaps

Well-sampled analytes (15+ samples)

  • Iron 65 samples
  • Manganese 63 samples
  • Arsenic 20 samples
  • Sulfate 65 samples
  • Chloride 66 samples
  • Fluoride 65 samples
  • HFPO-DA (GenX) 20 samples
  • Lead 20 samples
  • Nitrate 61 samples
  • Nitrite 43 samples
  • PFHxS 20 samples
  • PFNA 20 samples
  • PFOA 20 samples
  • PFOS 20 samples
  • Hardness 67 samples
  • PFBS 20 samples
  • pH 69 samples
  • Sodium 61 samples

Limited data (<15 samples) — interpret with caution

  • Radon 5 samples
  • Uranium 8 samples

CDC Health Outcome Correlations

Where contaminants detected in Marinette 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.

Contaminant Associated Condition Marinette County Prevalence WI Average Source Year
Arsenic Cancer prevalence 8.8% 7.0% 2020
Arsenic Kidney disease rate 3.6% 2.9% 2020

Source: CDC PLACES county-level estimates. Raw data: Download Marinette County CDC PLACES data →

Data Sources

This report aggregates data from the following public databases:

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 WI with at least one sample for that analyte.

Last updated: 2026-07-15

Full methodology →