Marin County, CA

ZIP 94920

In ZIP 94920, 4 of the 12 things we check have at least one part graded D or F.

• Drinking water: Treasure Island meets every EPA legal limit; 6 contaminants are above health goals, led by chloroform at 84× California’s Public Health Goal.
• Nearest Superfund site: Alameda Naval Air Station, 1.2 miles away (3 within 10 miles).
• Largest share of modeled toxic air from industry: Bio-Rad Laboratories Inc (64%), mostly acrylamide.
• Fine particles (PM2.5) average 9.2 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 21 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 94920

• Superfund sites nearbyA to F
• Factories and industrial sitesC to F
• Oil and gas wellsA
• Parks and nature nearbyA to B
• Air qualityC to F
• Drinking water qualityA to C
• Pesticide useA
• Neighborhood health statusA to C
• Past wildfire impactsA
• Past flood impactsA
• Noise levelsA to D
• Radiation signalsB

Based on 6 census tracts · compiled October 25, 2026 · how each grade works and its sources

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