Humboldt County, CA

ZIP 95546

In ZIP 95546, 5 of the 12 things we check have at least one part graded D or F.

• Drinking water: Willow Creek C.s.d. meets every EPA legal limit; 6 contaminants are above health goals, led by lead at 9.6× California’s Public Health Goal.
• Nearest Superfund site: Copper Bluff Mine, 0.9 miles away (2 within 10 miles).
• Fine particles (PM2.5) average 9.5 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 15,274 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 95546

• Superfund sites nearbyC to D
• Factories and industrial sitesA
• Oil and gas wellsA
• Parks and nature nearbyB
• Air qualityD to F
• Drinking water qualityC to D
• Pesticide useC to D
• Neighborhood health statusD to F
• Past wildfire impactsC
• Past flood impactsA
• Noise levelsA
• Radiation signalsB

Based on 2 census tracts · compiled September 10, 2026 · how each grade works and its sources

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