ZIP 78666 · Texas
San Marcos, TX
Low Level5 compounds detected
Trace detections — well below EPA limits
Plain English
01What this means for you
Very low PFAS concentrations were detected — well below the EPA's Maximum Contaminant Level. For most healthy adults, this represents a minimal incremental risk from drinking water. The most proportionate response is to note the result and check your utility's Consumer Confidence Report again next year. If you have specific health concerns or vulnerable household members, speaking with your doctor and optionally installing a certified point-of-use filter is a reasonable step.
02MAXWELL WSC
Low LevelPWSID · TX0280003
PFAS test results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
lithium | 9800.00ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 3.80ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 3.70ppt | No federal limit | — | Unregulated |
03CRYSTAL CLEAR SUD
Low LevelPWSID · TX0940015
PFAS test results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
PFBA Perfluorobutanoic acid | 5.60ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 4.00ppt | No federal limit | — | Unregulated |
04CITY OF SAN MARCOS
Low LevelPWSID · TX1050001
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 | 11300.00ppt | No federal limit | — | Unregulated |
PFBA Perfluorobutanoic acid | 11.40ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 4.20ppt | No federal limit | — | Unregulated |
05TEXAS STATE UNIVERSITY - SAN MARCOS
Low LevelPWSID · TX1050003
PFAS test results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
lithium | 9500.00ppt | No federal limit | — | Unregulated |
Note: ZIP code 78666 is served by 4 separate water utilities. Results above show data for each system independently.
Source & Methodology
About this data
Values shown are the highest single-sample concentration measured at entry points to the distribution system. Results reflect water quality at the treatment plant — aging pipes, building plumbing, and on-site storage can affect what actually reaches your tap. "Not detected" means below the MRL, not literally zero.
View raw EPA UCMR 5 occurrence data →Related
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