Home hazard report for 11740 — Greenlawn, NY
ZIP 11740 is served by Greenlawn Water District: no health-based violations since 2016, latest lead result 1 ppb, PFAS 2 detected. Suffolk County is in EPA radon zone 3.
No health-based violations reported since 2016.
90th-percentile lead in the latest round (Jan 2025). Lead comes mostly from household plumbing and service lines, so individual homes can be higher.
PFAS were detected, with PFOA and PFOS below 4.0 ppt (highest not detected).
Predicted average under 2 pCi/L — but any home can have high radon, so EPA still recommends a test.
FEMA’s overall natural-hazard risk for this census tract, relative to the rest of the U.S.
The nearest active Superfund site is 7.0 miles away.
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Where ZIP 11740 is
Dashed: ZIP area · blue: utility service area · scroll or pinch to zoomDrinking water: Greenlawn Water District
Health-based violations
No health-based violations reported since 2016.
Full record for Greenlawn Water District →
Other systems overlapping this ZIP: Suffolk County Water Authority, South Huntington Water District.
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 |
|---|---|---|---|
| PFPeA | 3.3 ppt | 2 of 24 | — |
| PFHxS | 3.2 ppt | 1 of 24 | — |
| PFOS | not detected | 0 of 24 | 4 ppt MCL |
| PFBS | not detected | 0 of 24 | — |
| PFHpA | not detected | 0 of 24 | — |
| PFNA | not detected | 0 of 24 | — |
| PFOA | not detected | 0 of 24 | 4 ppt MCL |
| PFDA | not detected | 0 of 24 | — |
| HFPO-DA (GenX) | not detected | 0 of 24 | — |
| PFBA | not detected | 0 of 24 | — |
| PFHxA | not detected | 0 of 24 | — |
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 Suffolk County
EPA radon zone 3 — low potential. Predicted average under 2 pCi/L — but any home can have high radon, so EPA still recommends a test.
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 →
Natural hazard risk
FEMA rates the overall natural-hazard risk of this neighborhood (census tract) as Very Low, with very low social vulnerability and very high community resilience.
FEMA National Risk Index (December 2025): expected annual losses from each hazard combined with social vulnerability and community resilience, rated relative to all U.S. census tracts. Hazards not listed are not applicable here. It describes the area, not a single building; flood insurance maps (FEMA FIRMs) decide flood-insurance requirements.
Live conditions: river gauges and flood levels · tornado warnings · wildfire detections · earthquakes — our sister maps, updated from NOAA, USGS and NASA every few minutes.
Superfund sites nearby
| Site | Status | Distance |
|---|---|---|
| Computer Circuits Hauppauge, New York · EPA ID NYD125499673 | Active (final NPL) | 7.0 mi |
| SMS Instruments, Inc. Deer Park, New York · EPA ID NYD001533165 | Cleaned up & deleted | 7.6 mi |
| Tronic Plating Co., Inc. Farmingdale, New York · EPA ID NYD002059517 | Cleaned up & deleted | 8.1 mi |
| Circuitron Corp. East Farmingdale, New York · EPA ID NYD981184229 | Active (final NPL) | 8.6 mi |
| Claremont Polychemical Old Bethpage, New York · EPA ID NYD002044584 | Active (final NPL) | 8.6 mi |
| Old Bethpage Landfill Oyster Bay, New York · EPA ID NYD980531727 | Active (final NPL) | 8.7 mi |
| Syosset Landfill Oyster Bay, New York · EPA ID NYD000511360 | Cleaned up & deleted | 9.0 mi |
| Kenmark Textile Corp. Farmingdale, New York · EPA ID NYD075784165 | Cleaned up & deleted | 9.4 mi |
| MacKenzie Chemical Works, Inc. Central Islip, New York · EPA ID NYD980753420 | Active (final NPL) | 9.7 mi |
| Smithtown Ground Water Contamination Smithtown, New York · EPA ID NY0002318889 | Cleaned up & deleted | 9.9 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 11740
Who supplies drinking water to ZIP 11740?
Greenlawn Water District (EPA ID NY5103271), a groundwater (wells) system serving about 42,000 people.
Is there lead in Greenlawn, NY tap water?
The utility’s latest 90th-percentile lead result (Jan 2025) 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 Greenlawn, NY water have PFAS?
PFAS were detected, with PFOA and PFOS below 4.0 ppt (highest not detected).
Has the water system in 11740 had violations?
No health-based violations reported since 2016.
What natural hazards affect ZIP 11740?
FEMA’s National Risk Index rates the overall natural-hazard risk here as Very Low; the highest-rated hazards are coastal flooding (relatively moderate), winter weather (relatively moderate), cold wave (relatively low).
Are there Superfund sites near 11740?
The nearest active Superfund site is 7.0 miles away. Sites within 10 miles: Computer Circuits (7.0 mi, Active (final NPL)); SMS Instruments, Inc. (7.6 mi, Cleaned up & deleted); Tronic Plating Co., Inc. (8.1 mi, Cleaned up & deleted).
Is radon a problem in Suffolk County?
Suffolk County is in EPA radon zone 3 (low potential). Predicted average under 2 pCi/L — but any home can have high radon, so EPA still recommends a test.