ZIP Code 94566
High RiskPFAS above EPA limits detected
5 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.
16
PFAS Detected
5
Above EPA Limits
2
Water Systems
650%
Highest % of MCL
Compounds Exceeding EPA Limits
PFOS Exceeds EPA limit
0 ppt MCL: 4 ppt 300% of limit
Detected: 12.00 ppt
PFOA Exceeds EPA limit
0 ppt MCL: 4 ppt 120% of limit
Detected: 4.80 ppt
PFHxS Exceeds EPA limit
0 ppt MCL: 10 ppt 220% of limit
Detected: 22.00 ppt
CALIFORNIA WATER SERVICE - LIVERMORE
CA0110003 High RiskWater Type
MX
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 | 12.00ppt | 300% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFOA Perfluorooctanoic acid | 4.80ppt | 120% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFHxS Perfluorohexane sulfonic acid | 9.80ppt | 98% of limit
| 10 ppt | Below limit |
lithium | 25100.00ppt | No federal limit | — | Unregulated |
PFBS Perfluorobutane sulfonic acid | 4.20ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 3.90ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 3.60ppt | No federal limit | — | Unregulated |
CITY OF PLEASANTON
CA0110008 High RiskWater Type
Groundwater
PFAS Detected
9
Above MCL
3
State
California
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
PFOS Perfluorooctane sulfonic acid | 26.00ppt | 650% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFHxS Perfluorohexane sulfonic acid | 22.00ppt | 220% of limit
| 10 ppt | ⚠ Exceeds MCL |
PFOA Perfluorooctanoic acid | 5.10ppt | 128% of limit
| 4 ppt | ⚠ Exceeds MCL |
lithium | 16800.00ppt | No federal limit | — | Unregulated |
PFBA Perfluorobutanoic acid | 6.30ppt | No federal limit | — | Unregulated |
PFBS Perfluorobutane sulfonic acid | 6.10ppt | No federal limit | — | Unregulated |
PFPeS | 4.30ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 4.10ppt | No federal limit | — | Unregulated |
Show 1 more compound detected at low levels
| PFPeAPerfluoropentanoic acid | 4.10 ppt | No federal limit |
Note: ZIP code 94566 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.