ZIP Code 29420
High RiskPFAS above EPA limits detected
4 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.
10
PFAS Detected
4
Above EPA Limits
2
Water Systems
163%
Highest % of MCL
Compounds Exceeding EPA Limits
PFOS Exceeds EPA limit
0 ppt MCL: 4 ppt 163% of limit
Detected: 6.50 ppt
PFOA Exceeds EPA limit
0 ppt MCL: 4 ppt 110% of limit
Detected: 4.40 ppt
CHARLESTON WATER SYSTEM (SC1010001)
SC1010001 High RiskWater Type
Surface Water
PFAS Detected
5
Above MCL
2
State
South Carolina
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
PFOS Perfluorooctane sulfonic acid | 6.50ppt | 163% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFOA Perfluorooctanoic acid | 4.40ppt | 110% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFPeA Perfluoropentanoic acid | 4.70ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 4.30ppt | No federal limit | — | Unregulated |
PFBS Perfluorobutane sulfonic acid | 3.80ppt | No federal limit | — | Unregulated |
DCWS ASHLEY PHOSPHATE (1820008)
SC1820008 High RiskWater Type
Surface Water
PFAS Detected
5
Above MCL
2
State
South Carolina
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
PFOS Perfluorooctane sulfonic acid | 5.50ppt | 138% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFOA Perfluorooctanoic acid | 4.30ppt | 108% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFPeA Perfluoropentanoic acid | 4.80ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 4.20ppt | No federal limit | — | Unregulated |
PFBS Perfluorobutane sulfonic acid | 3.60ppt | No federal limit | — | Unregulated |
Note: ZIP code 29420 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.