ZIP Code 91710
High RiskPFAS above EPA limits detected
3 compounds exceed EPA Maximum Contaminant Levels in water serving this ZIP code. Standard pitcher filters like Brita do not remove PFAS. See filter recommendations below.
12
PFAS Detected
3
Above EPA Limits
2
Water Systems
450%
Highest % of MCL
Compounds Exceeding EPA Limits
PFOS Exceeds EPA limit
0 ppt MCL: 4 ppt 450% of limit
Detected: 18.00 ppt
PFOA Exceeds EPA limit
0 ppt MCL: 4 ppt 178% of limit
Detected: 7.10 ppt
POMONA - CITY, WATER DEPT.
CA1910126 High RiskWater Type
Groundwater
PFAS Detected
7
Above MCL
2
State
California
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
PFOS Perfluorooctane sulfonic acid | 18.00ppt | 450% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFOA Perfluorooctanoic acid | 7.10ppt | 178% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFHxS Perfluorohexane sulfonic acid | 7.90ppt | 79% of limit
| 10 ppt | Below limit |
lithium | 9300.00ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 4.40ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 4.10ppt | No federal limit | — | Unregulated |
PFBS Perfluorobutane sulfonic acid | 3.20ppt | No federal limit | — | Unregulated |
MONTE VISTA CWD
CA3610029 High RiskWater Type
Groundwater
PFAS Detected
5
Above MCL
1
State
California
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
PFOS Perfluorooctane sulfonic acid | 5.60ppt | 140% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFHxS Perfluorohexane sulfonic acid | 7.40ppt | 74% of limit
| 10 ppt | Below limit |
PFBA Perfluorobutanoic acid | 11.00ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 3.50ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 3.30ppt | No federal limit | — | Unregulated |
Note: ZIP code 91710 is served by 2 separate water utilities.
Results above show data for each system independently.
Data source: EPA Unregulated Contaminant Monitoring Rule, 5th cycle (UCMR 5) — January 2026 release.
UCMR 5 tested ~10,000 public water systems serving more than 25 people between 2023-2025 for 29 PFAS compounds.
Detection values represent the highest single-sample result measured at entry points to the distribution system.