PlainWater

MO AMERICAN ST LOUIS ST CHARLES COUNTIES

PWS ID: MO6010716 · CHESTERFIELD, Missouri 63017-2103

PFAS Detected

2 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.

Population Served
1,111,000
Total Violations
9
Health-Based Violations
8
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Private
Connections
372,374
County
St. Louis
School/Daycare
No
MCL Violations
0
Monitoring Violations
1
Treatment Tech Violations
8

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Interim Enhanced Surface Water Treatment Rule TT 8 2010
Interim Enhanced Surface Water Treatment Rule MR 1 2005

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 18 of 720 samples detected PFAS.

Contaminant Date Result MRL Status
PFOS 9/11/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFOA 9/11/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFDA 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFDoA 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFHxA 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFMBA 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFPeA 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
4:2 FTS 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFBS 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFNA 9/11/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFHpA 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFUnA 9/11/2024 <0.002 µg/L 0.002 µg/L Not Detected
11Cl-PF3OUdS 9/11/2024 <0.005 µg/L 0.005 µg/L Not Detected
lithium 9/11/2024 84.6000 µg/L 9 µg/L Detected
9Cl-PF3ONS 9/11/2024 <0.002 µg/L 0.002 µg/L Not Detected
ADONA 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
HFPO-DA 9/11/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFTA 9/11/2024 <0.008 µg/L 0.008 µg/L Not Detected
6:2 FTS 9/11/2024 <0.005 µg/L 0.005 µg/L Not Detected
8:2 FTS 9/11/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFMPA 9/11/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFHxS 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFHpS 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFPeS 9/11/2024 <0.004 µg/L 0.004 µg/L Not Detected
NFDHA 9/11/2024 <0.02 µg/L 0.02 µg/L Not Detected
PFEESA 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
NMeFOSAA 9/11/2024 <0.006 µg/L 0.006 µg/L Not Detected
NEtFOSAA 9/11/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFTrDA 9/11/2024 <0.007 µg/L 0.007 µg/L Not Detected
PFBA 9/11/2024 <0.005 µg/L 0.005 µg/L Not Detected
lithium 9/11/2024 80.6000 µg/L 9 µg/L Detected
HFPO-DA 9/11/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFBA 9/11/2024 <0.005 µg/L 0.005 µg/L Not Detected
6:2 FTS 9/11/2024 <0.005 µg/L 0.005 µg/L Not Detected
8:2 FTS 9/11/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFMPA 9/11/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFPeA 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFMBA 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFEESA 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFPeS 9/11/2024 <0.004 µg/L 0.004 µg/L Not Detected
9Cl-PF3ONS 9/11/2024 <0.002 µg/L 0.002 µg/L Not Detected
11Cl-PF3OUdS 9/11/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFHpS 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
4:2 FTS 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
NFDHA 9/11/2024 <0.02 µg/L 0.02 µg/L Not Detected
NEtFOSAA 9/11/2024 <0.005 µg/L 0.005 µg/L Not Detected
ADONA 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
NMeFOSAA 9/11/2024 <0.006 µg/L 0.006 µg/L Not Detected
PFTrDA 9/11/2024 <0.007 µg/L 0.007 µg/L Not Detected
PFBS 9/11/2024 <0.003 µg/L 0.003 µg/L Not Detected
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. PFAS data from EPA UCMR5 monitoring program (2023-2025). This data is provided for informational purposes only.