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Public environmental health records for water, air, land, infrastructure, incidents, and community indicators.
Toxin Scout summarizes public records from government and public datasets. Data can be delayed, incomplete, approximate, matched at non-parcel levels, or have accuracy problems as a result of this product's beta status, so verify important findings against the linked source records.
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Preparing Diamond Bar environmental records...
Drinking water compliance, PFAS records, natural water body health, discharge permits, and water-quality monitoring records for Diamond Bar.
Public water-system records for Diamond Bar, CA from EPA SDWIS.
Pomona - City, Water Dept.
PFAS above an official threshold detected in available EPA records.
Reviewed: active/open records as of Q1 2026
City-area ZIP code · Serves 151,713 people
Upland, City of
Active monitoring or reporting issue detected in EPA SDWIS.
Reviewed: active/open records as of Q1 2026
City-area ZIP code · Serves 78,376 people
Whittier-City, Water Dept.
No active drinking-water issues detected in EPA SDWIS.
Reviewed: active/open records as of Q1 2026
City-area ZIP code · Serves 49,954 people
Data from EPA SDWIS
PFAS screening separates EPA UCMR5 drinking-water monitoring from nearby DoD PFAS investigation-site records; EPA samples shown are from Aug 2023 to Oct 2024.
Drinking Water PFAS Monitoring
EPA UCMR5 samples public water systems. These results are separate from nearby PFAS cleanup or investigation-site records.
4 PFAS sample results above EPA limits
Sample period: Aug 2023 to Apr 2024
UCMR5 results are sampled by public water system, not every household. Confirm your water provider before treating these as tap-water results for a specific address.
| Chemical | Concentration (µg/L) | EPA Limit (µg/L) | Sample date | Over Limit |
|---|---|---|---|---|
| PFOS | 0.0180 | 0.0040 | 2024-04-25 | Yes |
| PFOS | 0.0110 | 0.0040 | 2023-08-23 | Yes |
| PFOA | 0.0071 | 0.0040 | 2024-04-25 | Yes |
| PFOA | 0.0058 | 0.0040 | 2023-08-23 | Yes |
PFAS detections below EPA limits.
Nearby PFAS Investigation Sites
DoD records are nearby site investigations, not Diamond Bar drinking-water detections. Record names come from the source database and can be broad.
No DoD PFAS investigation site records surfaced within the search radius.
No health-relevant impaired water body records surfaced within 10 km in EPA ATTAINS.
Data from EPA ATTAINS
NPDES permits regulate pollutant discharges into U.S. waterways. Facilities must report compliance quarterly.
Violation records
Last inspected: Dec 2025
Last inspected: Dec 2025
Data from EPA ECHO
Air quality data from EPA monitoring stations, facility emissions inventories, and area-level air-quality designations in this city.
Los Angeles County
Reported: Dec 2020
EPA national average is ~30 per million
According to EPA, a cancer risk of 40-in-1-million means that for every 1 million people continuously exposed to these air toxics over a 70-year lifetime, an estimated 40 may develop cancer from that exposure. This is in addition to cancer risk from all other causes.
Top local emission sources
Data from EPA AirToxScreen
This area meets EPA's National Ambient Air Quality Standards (NAAQS) for all criteria pollutants
No nonattainment designations apply to this location.
Anaheim
Annual mean: 0.4 ppm · EPA standard: 9 ppm
Reported: Mar 2026
Annual mean: 10.5 μg/m³ · EPA standard: 9 μg/m³
Reported: Mar 2026
Annual mean: 19.3 μg/m³ · EPA standard: 150 μg/m³
Reported: Mar 2026
Data from EPA AQS
Reviewed: source records as of Q4 2025
TRI releases are self-reported annual totals (calendar year 2024). Hover fugitive or stack for definitions.
Natvar
Reported: 2024
Contaminated sites, waste facilities, cleanup records, and industrial operations in this city.
Reviewed: source query run Jun 2026
Reviewed: source query run Jun 2026
No underground storage tank records with active/open release status surfaced within 2 miles.
Data from EPA UST Finder
Reviewed: reporting year 2024
Los Angeles County, CA
Reported: Mar 2026
Los Angeles County is EPA Radon Zone 2 (moderate potential). EPA defines Zone 2 counties as having predicted average indoor screening levels between 2 pCi/L and 4 pCi/L.
Radon levels can vary from home to home, so EPA recommends testing the property to know its indoor level.
Flood-map status, chemical accident risk, nuclear facilities, pipeline incidents, and community health indicators in this city.
Risk Management Program facilities handle extremely hazardous substances (e.g., chlorine, ammonia, propane). EPA requires these facilities to plan for worst-case chemical releases.
No facility records with recent chemical accidents surfaced for this property within the last five years.
Data from EPA ECHO
PHMSA tracks incidents involving natural gas and hazardous liquid pipelines. Incidents include leaks, ruptures, and explosions.
Recent Incidents (last 5 years)
SOUTHERN CALIFORNIA GAS CO
Reported: Jan 1, 2023
Property damage: $15,000
Data from PHMSA
Health outcomes from County Health Rankings. Values shown alongside state and national averages.
Los Angeles County, CaliforniaPop. 9,721,138
Reported: Mar 2026
Premature Death
Poor or Fair Health
Poor Physical Health Days
Poor Mental Health Days
Adult Smoking
Adult Obesity
Air Pollution - Particulate Matter
Drinking Water Violations
Diabetes Prevalence
Life Expectancy
| Indicator | County | State | National |
|---|---|---|---|
| Premature Death | 6,317 | 6,373 | 7,972 |
| Poor or Fair Health | 18.2% | 15.8% | 14.2% |
| Poor Physical Health Days | 3.5 | 3.1 | 3.3 |
| Poor Mental Health Days | 5.1 | 4.7 | 4.8 |
| Adult Smoking | 11.0% | 8.8% | 15.0% |
| Adult Obesity | 28.5% | 27.8% | 34.0% |
| Air Pollution - Particulate Matter | 13.4 | 7.1 | 7.3 |
| Drinking Water Violations | 1 | 1 | N/A |
| Diabetes Prevalence | 11.7% | 10.8% | 9.6% |
| Life Expectancy | 80.1 | 79.9 | 77.6 |