Marathon County, WI

ZIP 54421

In ZIP 54421, 6 of the 12 things we check have at least one part graded D or F.

• Drinking water: Clark County Rehabilitation & Living Center meets every EPA legal limit; 10 contaminants are above health goals, led by lead at 5,187× California’s Public Health Goal.
• Nearest Superfund site: Unity Auto Mart, 7.1 miles away.
• Largest share of modeled toxic air from industry: Veritas Steel (43%), mostly chromium.
• Fine particles (PM2.5) average 6.7 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 185,897 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 54421

• Superfund sites nearbyC to D
• Factories and industrial sitesB to C
• Oil and gas wellsA
• Parks and nature nearbyD
• Air qualityA to B
• Drinking water qualityC to F
• Pesticide useF
• Neighborhood health statusD
• Past wildfire impactsA
• Past flood impactsA
• Noise levelsA to D
• Radiation signalsC

Based on 4 census tracts · compiled September 10, 2026 · how each grade works and its sources

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