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Community Water System · PWS MO6024292

Jefferson County PWSD 1

Operator location Arnold, Missouri - 0% of 2 violations are health-based (lower-third health share (≤ 1%)); surface water source; 21,113 served per SDWIS.

21,113
People served (this PWS)
2
EPA violations (this PWS)
0
Health-based (this PWS)
No PFAS
UCMR5 (this PWS)
Follow published updates (RSS)

Jefferson County PWSD 1 standing, low SDWIS violation third

0% of 2 recorded violations are health-based - lower-third health share (≤ 1%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 0% is lower-third health share (≤ 1%). UCMR5: UCMR5 tested, none detected. Population rank #2,592 of 29,740 among systems serving 500+.

The verdict

Jefferson County PWSD 1 is in the lower third by violation count (2; lower-third violation load (≤ 21 violations)). A low count does not mean the system is unmonitored - monitoring and reporting violations still appear in SDWIS. Population served is large (21,113; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is only 0% - almost all of this trail is monitoring or reporting. UCMR5 tested this system and reported no PFAS above the minimum reporting level.

#2,592 of 29,740
Population · /systems
#31 of 738
Population · MO
2
Total EPA violations on record
0%
Health-based (MCL / treatment failure)

Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.

System Details

System Type
Community
Owner Type
Local
Connections
7,558
County
Jefferson
School/Daycare
No
MCL Violations
0
Monitoring Violations
0
Treatment Tech Violations
0

Violation Count vs. the National Corpus

Jefferson County PWSD 1 has 2 recorded EPA violations, 5% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 93% carry more. 0% of this system's own violations are health-based (0 of 2), and it ranks #2,592 of 29,740 by population served among that same cohort.

EPA violations vs. the national water-system corpus

Public water systems serving 500+ people (EPA SDWIS)

2 Among the lowest violation counts fewer violations than 93% of 29,740 water systems

the national water-system corpus, bucketed by value

Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source EPA SDWIS · 2026-05-15

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 116 samples detected PFAS.

Contaminant Date Result MRL Status
8:2 FTS 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
PFBS 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFHpA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFNA 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
PFOA 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
PFDA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFDoA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFHpS 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeS 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
NFDHA 9/23/2024 <20.00 ppt 20.00 ppt Not Detected
PFEESA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFMBA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFMPA 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
PFHxS 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
4:2 FTS 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
PFBA 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
HFPO-DA 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
ADONA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 9/23/2024 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
PFUnA 9/23/2024 <2.00 ppt 2.00 ppt Not Detected
PFHxA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
NEtFOSAA 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
PFPeA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFTrDA 9/23/2024 <7.00 ppt 7.00 ppt Not Detected
PFTA 9/23/2024 <8.00 ppt 8.00 ppt Not Detected
PFOS 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
NMeFOSAA 9/23/2024 <6.00 ppt 6.00 ppt Not Detected
PFHpA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFHxA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFDoA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFDA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFOS 6/3/2024 <4.00 ppt 4.00 ppt Not Detected
PFHxS 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 6/3/2024 <2.00 ppt 2.00 ppt Not Detected
PFBS 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
NMeFOSAA 6/3/2024 <6.00 ppt 6.00 ppt Not Detected
NEtFOSAA 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 6/3/2024 <7.00 ppt 7.00 ppt Not Detected
PFTA 6/3/2024 <8.00 ppt 8.00 ppt Not Detected
PFNA 6/3/2024 <4.00 ppt 4.00 ppt Not Detected
11Cl-PF3OUdS 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
ADONA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFBA 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFMPA 6/3/2024 <4.00 ppt 4.00 ppt Not Detected

Health-based violations on Jefferson County PWSD 1

0 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for MO6024292.

Sources: EPA SDWIS · Missouri DNR, Public Drinking Water Branch

Nationwide peers

2 violations · 21,113 served: nearest cross-state SDWIS matches.

What to do with Jefferson County PWSD 1

Use this system's EPA-reported record as a starting filter, not a final verdict.

  • See how every tracked system in Missouri compares on the same EPA violation measures. Missouri systems
  • Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
  • Find and compare another public water system by name or PWSID. Search systems

EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater