ZIP Code 78570
Moderate8
PFAS Detected
0
Above EPA Limits
2
Water Systems
34%
Highest % of MCL
CITY OF MERCEDES
TX1080007 Low LevelWater Type
MX
PFAS Detected
2
Above MCL
0
State
Texas
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
lithium | 61400.00ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 3.30ppt | No federal limit | — | Unregulated |
NORTH ALAMO WSC
TX1080029 ModerateWater Type
Groundwater
PFAS Detected
6
Above MCL
0
State
Texas
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
PFHxS Perfluorohexane sulfonic acid | 3.40ppt | 34% of limit
| 10 ppt | Below limit |
lithium | 50000.00ppt | No federal limit | — | Unregulated |
PFBA Perfluorobutanoic acid | 12.20ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 3.80ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 3.50ppt | No federal limit | — | Unregulated |
PFBS Perfluorobutane sulfonic acid | 3.00ppt | No federal limit | — | Unregulated |
Note: ZIP code 78570 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.