PlainWater

SOUTH MESA WC

PWS ID: CA3310017 · CALIMESA, California 92320

PFAS Detected

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

Population Served
10,108
Total Violations
14
Health-Based Violations
4
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
3,108
County
Riverside
School/Daycare
No
MCL Violations
4
Monitoring Violations
9
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Fluoride MCL 4 2014
Lead and Copper Rule MR 3 2013
Total Haloacetic Acids (HAA5) MR 2 2009
Fluoride MR 2 2010
TTHM MR 2 2009

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 6 of 480 samples detected PFAS.

Contaminant Date Result MRL Status
PFMPA 9/20/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFPeA 9/20/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFMBA 9/20/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFBS 9/20/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFEESA 9/20/2023 <0.003 µg/L 0.003 µg/L Not Detected
NFDHA 9/20/2023 <0.02 µg/L 0.02 µg/L Not Detected
PFPeS 9/20/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFHpS 9/20/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFDA 9/20/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFHpA 9/20/2023 <0.003 µg/L 0.003 µg/L Not Detected
8:2 FTS 9/20/2023 <0.005 µg/L 0.005 µg/L Not Detected
PFNA 9/20/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFHxS 9/20/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFOA 9/20/2023 <0.004 µg/L 0.004 µg/L Not Detected
4:2 FTS 9/20/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFDoA 9/20/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFHxA 9/20/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFUnA 9/20/2023 <0.002 µg/L 0.002 µg/L Not Detected
11Cl-PF3OUdS 9/20/2023 <0.005 µg/L 0.005 µg/L Not Detected
9Cl-PF3ONS 9/20/2023 <0.002 µg/L 0.002 µg/L Not Detected
ADONA 9/20/2023 <0.003 µg/L 0.003 µg/L Not Detected
HFPO-DA 9/20/2023 <0.005 µg/L 0.005 µg/L Not Detected
PFBA 9/20/2023 <0.005 µg/L 0.005 µg/L Not Detected
6:2 FTS 9/20/2023 <0.005 µg/L 0.005 µg/L Not Detected
PFOS 9/20/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFEESA 9/13/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFUnA 9/13/2023 <0.002 µg/L 0.002 µg/L Not Detected
11Cl-PF3OUdS 9/13/2023 <0.005 µg/L 0.005 µg/L Not Detected
9Cl-PF3ONS 9/13/2023 <0.002 µg/L 0.002 µg/L Not Detected
ADONA 9/13/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFBA 9/13/2023 <0.005 µg/L 0.005 µg/L Not Detected
4:2 FTS 9/13/2023 <0.003 µg/L 0.003 µg/L Not Detected
8:2 FTS 9/13/2023 <0.005 µg/L 0.005 µg/L Not Detected
PFMPA 9/13/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFPeS 9/13/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFMBA 9/13/2023 <0.003 µg/L 0.003 µg/L Not Detected
HFPO-DA 9/13/2023 <0.005 µg/L 0.005 µg/L Not Detected
NFDHA 9/13/2023 <0.02 µg/L 0.02 µg/L Not Detected
PFPeA 9/13/2023 0.0089 µg/L 0.003 µg/L Detected
PFHpS 9/13/2023 <0.003 µg/L 0.003 µg/L Not Detected
6:2 FTS 9/13/2023 <0.005 µg/L 0.005 µg/L Not Detected
PFDoA 9/13/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFHxA 9/13/2023 0.0068 µg/L 0.003 µg/L Detected
PFBS 9/13/2023 0.0047 µg/L 0.003 µg/L Detected
PFHpA 9/13/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFHxS 9/13/2023 0.0035 µg/L 0.003 µg/L Detected
PFNA 9/13/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFOS 9/13/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFOA 9/13/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFDA 9/13/2023 <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.