Contra Costa County, CA

ZIP 94520

In ZIP 94520, 6 of the 12 things we check have at least one part graded D or F.

• Drinking water: City Of Pittsburg meets every EPA legal limit; 12 contaminants are above health goals, led by arsenic at 744× California’s Public Health Goal.
• Nearest Superfund site: Concord Naval Weapons Station, 2.3 miles away.
• Largest share of modeled toxic air from industry: Shell Catalysts & Technologies - Pittsburg (32%), mostly cobalt compounds.
• Fine particles (PM2.5) average 9.1 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 98,092 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 94520

• Superfund sites nearbyD to F
• Factories and industrial sitesD to F
• Oil and gas wellsB to F
• Parks and nature nearbyA to C
• Air qualityD to F
• Drinking water qualityC
• Pesticide useB to D
• Neighborhood health statusA to C
• Past wildfire impactsA
• Past flood impactsA
• Noise levelsA to D
• Radiation signalsA to C

Based on 16 census tracts · compiled October 25, 2026 · how each grade works and its sources

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