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Community Water System · PWS OK1020210

Sequoyah Co. RWD #8

Operator location Sallisaw, Oklahoma - larger served population (> 3,309) at 13,460 people served; 199 SDWIS violations on record from surface water sources.

13,460
People served (this PWS)
199
EPA violations (this PWS)
31
Health-based (this PWS)
No PFAS
UCMR5 (this PWS)
Follow published updates (RSS)

Sequoyah Co. RWD #8 standing, high SDWIS violation third

13,460 people served (SDWIS) - larger served population (> 3,309). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 16% is middle-third health share (≤ 23%). UCMR5: UCMR5 tested, none detected. Population rank #3,767 of 29,740 among systems serving 500+.

The verdict

Sequoyah Co. RWD #8 sits in the upper third of the sitemap cohort by violation count (199), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (13,460; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 16% (middle-third health share (≤ 23%)). UCMR5 tested this system and reported no PFAS above the minimum reporting level.

#3,767 of 29,740
Population · /systems
#43 of 558
Population · OK
199
Total EPA violations on record
16%
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
5,386
County
Sequoyah
School/Daycare
No
MCL Violations
18
Monitoring Violations
135
Treatment Tech Violations
13

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
CARBON, TOTAL MR 24 2007
Surface Water Treatment Rule TT 12 2021
Total Haloacetic Acids (HAA5) MCL 12 2003
Coliform (TCR) MR 7 2008
Chlorine MR 7 2025
Revised Total Coliform Rule MON 7 2025
Coliform (TCR) MCL 6 2015
1,2,4-Trichlorobenzene MR 4 2020
cis-1,2-Dichloroethylene MR 4 2020
Xylenes, Total MR 4 2020
o-Dichlorobenzene MR 4 2020
1,1-Dichloroethylene MR 4 2020
1,1,1-Trichloroethane MR 4 2020
Carbon tetrachloride MR 4 2020
1,2-Dichloropropane MR 4 2020
1,1,2-Trichloroethane MR 4 2020
Tetrachloroethylene MR 4 2020
Benzene MR 4 2020
Styrene MR 4 2020
DICHLOROMETHANE MR 4 2020
Vinyl chloride MR 4 2020
1,2-Dichloroethane MR 4 2020
CHLOROBENZENE MR 4 2020
Ethylbenzene MR 4 2020
Trichloroethylene MR 4 2020
Toluene MR 4 2020
p-Dichlorobenzene MR 4 2020
trans-1,2-Dichloroethylene MR 4 2020
Surface Water Treatment Rule MR 2 2000
TTHM MR 2 2013

Violation Count vs. the National Corpus

Sequoyah Co. RWD #8 has 199 recorded EPA violations, 85% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 15% carry more. 16% of this system's own violations are health-based (31 of 199), and it ranks #3,767 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)

199 Higher than most more violations than 85% 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
PFMBA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
ADONA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 9/18/2023 <5.00 ppt 5.00 ppt Not Detected
PFBA 9/18/2023 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 9/18/2023 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 9/18/2023 <5.00 ppt 5.00 ppt Not Detected
PFPeA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFEESA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 9/18/2023 <20.00 ppt 20.00 ppt Not Detected
PFPeS 9/18/2023 <4.00 ppt 4.00 ppt Not Detected
PFMPA 9/18/2023 <4.00 ppt 4.00 ppt Not Detected
PFTA 9/18/2023 <8.00 ppt 8.00 ppt Not Detected
11Cl-PF3OUdS 9/18/2023 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 9/18/2023 <6.00 ppt 6.00 ppt Not Detected
9Cl-PF3ONS 9/18/2023 <2.00 ppt 2.00 ppt Not Detected
PFTrDA 9/18/2023 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 9/18/2023 <5.00 ppt 5.00 ppt Not Detected
PFBS 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxS 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFOS 9/18/2023 <4.00 ppt 4.00 ppt Not Detected
PFOA 9/18/2023 <4.00 ppt 4.00 ppt Not Detected
PFDA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFDoA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpS 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFUnA 9/18/2023 <2.00 ppt 2.00 ppt Not Detected
PFNA 9/18/2023 <4.00 ppt 4.00 ppt Not Detected
PFHpS 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFTA 6/3/2024 <8.00 ppt 8.00 ppt Not Detected
NEtFOSAA 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFDoA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 6/3/2024 <7.00 ppt 7.00 ppt Not Detected
PFHxA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFUnA 6/3/2024 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 6/3/2024 <6.00 ppt 6.00 ppt Not Detected
PFHpA 6/3/2024 <3.00 ppt 3.00 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
PFPeA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFMBA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFEESA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
NFDHA 6/3/2024 <20.00 ppt 20.00 ppt Not Detected
PFBS 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFDA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFHxS 6/3/2024 <3.00 ppt 3.00 ppt Not Detected

Population served record for Sequoyah Co. RWD #8

EPA SDWIS lists 13,460 people served and 5,386 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.

Sources: EPA SDWIS

Nationwide peers

199 violations · 13,460 served: nearest cross-state SDWIS matches.

Cross-state systems with comparable violation load

Nearest cross-state community systems (500+ served) by total SDWIS violations on record.

4 peers

Cross-state systems with similar served population

Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).

4 peers

What to do with Sequoyah Co. RWD #8

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

  • See how every tracked system in Oklahoma compares on the same EPA violation measures. Oklahoma 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