Riverside County, CA

ZIP 92551

In ZIP 92551, 8 of the 12 things we check have at least one part graded D or F.

• Drinking water: Eastern Municipal Wd has 4 contaminants at or over an EPA legal limit; 27 contaminants are above health goals, led by pfhxs at 15× California Notification Level.
• Nearest Superfund site: March Air Force Base, 3.4 miles away.
• Largest share of modeled toxic air from industry: Sterigenics-Ontario Facility (43%), mostly ethylene oxide.
• Fine particles (PM2.5) average 9.4 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 1,172,577 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 92551

• Superfund sites nearbyD to F
• Factories and industrial sitesD
• Oil and gas wellsA
• Parks and nature nearbyC to F
• Air qualityF
• Drinking water qualityF
• Pesticide useD to F
• Neighborhood health statusB to C
• Past wildfire impactsC to D
• Past flood impactsC
• Noise levelsA to C
• Radiation signalsC to D

Based on 8 census tracts · compiled September 10, 2026 · how each grade works and its sources

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