Home hazard report for 91009 — Duarte, CA
ZIP 91009 is served by Cal-Am Water Company - Duarte: no health-based violations since 2016, latest lead result 1 ppb, PFAS 5.1 ppt. Los Angeles is in EPA radon zone 2.
No health-based violations reported since 2016.
90th-percentile lead in the latest round (Jan 2022). Lead comes mostly from household plumbing and service lines, so individual homes can be higher.
Highest PFOA or PFOS result in EPA’s 2023–2025 testing was at or above 4.0 ppt, EPA’s 2024 maximum contaminant level for each. 1 PFAS compound detected.
Predicted average indoor radon between 2 and 4 pCi/L. Test your home; many homes here exceed 4 pCi/L.
Active or proposed Superfund (National Priorities List) sites near the center of this ZIP code.
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Where ZIP 91009 is
blue: utility service area · scroll or pinch to zoomDrinking water: Cal-Am Water Company - Duarte
Health-based violations
No health-based violations reported since 2016.
Lead
90th-percentile lead per sampling round (90% of the homes sampled were at or below this level). Black line: EPA’s 15 ppb action level; under the Lead and Copper Rule Improvements the action level becomes 10 ppb from 2027.
PFAS (“forever chemicals”)
| Compound | Highest result | Samples with detection | EPA limit |
|---|---|---|---|
| PFOS | 5.1 ppt | 1 of 16 | 4 ppt MCL |
| PFHxA | not detected | 0 of 16 | — |
| PFDA | not detected | 0 of 16 | — |
| PFOA | not detected | 0 of 16 | 4 ppt MCL |
| PFNA | not detected | 0 of 16 | — |
| PFHxS | not detected | 0 of 16 | — |
| PFHpA | not detected | 0 of 16 | — |
| PFBS | not detected | 0 of 16 | — |
| HFPO-DA (GenX) | not detected | 0 of 16 | — |
| PFBA | not detected | 0 of 16 | — |
| PFPeA | not detected | 0 of 16 | — |
EPA Fifth Unregulated Contaminant Monitoring Rule (UCMR 5), samples 2023–2025; ppt = parts per trillion (ng/L). The 4.0 ppt maximum contaminant levels for PFOA and PFOS were set by EPA in 2024; water systems have until the end of the decade to comply.
Radon in Los Angeles
EPA radon zone 2 — moderate potential. Predicted average indoor radon between 2 and 4 pCi/L. Test your home; many homes here exceed 4 pCi/L.
Radon is a colorless, odorless radioactive gas from soil and rock, and the leading cause of lung cancer among non-smokers. EPA recommends fixing a home at 4 pCi/L or above and considering it from 2 pCi/L. A short-term test kit costs about $15–30. How radon zones work →
Superfund sites nearby
| Site | Status | Distance |
|---|---|---|
| San Gabriel Valley (Area 1) El Monte, California · EPA ID CAD980677355 | Active (final NPL) | 1.6 mi |
| San Gabriel Valley (Area 2) Baldwin Park Area, California · EPA ID CAD980818512 | Active (final NPL) | 5.1 mi |
| San Gabriel Valley (Area 4) La Puente, California · EPA ID CAD980817985 | Active (final NPL) | 8.6 mi |
| San Gabriel Valley (Area 3) Alhambra, California · EPA ID CAD980818579 | Active (final NPL) | 8.9 mi |
EPA Superfund National Priorities List (NPL): the country’s most serious known hazardous-waste sites, each with an EPA cleanup record (linked). Distance is measured from the ZIP center to the site’s reference point; being near a site does not by itself mean exposure — EPA site pages describe what was found and how it is being cleaned up.
What this is — and isn’t. These are records your water utility and state reported to the EPA, and the EPA’s radon map for your county. They describe the system and the area, not the water from your own tap or the air in your home. For that, read your utility’s annual Consumer Confidence Report and test: lead and radon tests are inexpensive.
Questions about 91009
Who supplies drinking water to ZIP 91009?
Cal-Am Water Company - Duarte (EPA ID CA1910186), a groundwater (wells) system serving about 24,767 people.
Is there lead in Duarte, CA tap water?
The utility’s latest 90th-percentile lead result (Jan 2022) was 1 ppb; EPA’s action level is 15 ppb, falling to 10 ppb from 2027. Lead mostly comes from service lines and home plumbing, so the only way to know your tap is to test it.
Does Duarte, CA water have PFAS?
Highest PFOA or PFOS result in EPA’s 2023–2025 testing was at or above 4.0 ppt, EPA’s 2024 maximum contaminant level for each. 1 PFAS compound detected.
Has the water system in 91009 had violations?
No health-based violations reported since 2016.
Are there Superfund sites near 91009?
Active or proposed Superfund (National Priorities List) sites near the center of this ZIP code. Sites within 10 miles: San Gabriel Valley (Area 1) (1.6 mi, Active (final NPL)); San Gabriel Valley (Area 2) (5.1 mi, Active (final NPL)); San Gabriel Valley (Area 4) (8.6 mi, Active (final NPL)).
Is radon a problem in Los Angeles?
Los Angeles is in EPA radon zone 2 (moderate potential). Predicted average indoor radon between 2 and 4 pCi/L. Test your home; many homes here exceed 4 pCi/L.