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Community Water System · PWS OK1020210

Sequoyah Co. RWD #8

Sallisaw, Oklahoma 74955-0627 - drinking water served from surface water sources to 13,460 people, tracked in EPA SDWIS and UCMR5.

13,460
People served
199
EPA violations
31
Health-based
No PFAS
UCMR5 result

The verdict

EPA records 199 drinking-water violations at Sequoyah Co. RWD #8, 16% of them health-based - below the Oklahoma per-system average.

199
Total EPA violations on record
16%
Health-based (MCL / treatment failure)
13,460
People served by this system
0
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Sequoyah Co. RWD #8

Sequoyah Co. RWD #8 is a local-owned community water system that delivers drinking water to 13,460 residents in Sallisaw, Oklahoma (Sequoyah County) through 5,386 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 199 total violations for this system , of which 31 (16%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 135 monitoring and reporting violations are on file. The most recent violation on record dates to 2025.

The most frequently cited contaminant at this system is CARBON, TOTAL, recorded in 24 violations (MR). This system was sampled under EPA's UCMR5 PFAS monitoring program and no PFAS compounds were detected above the minimum reporting level.

Across Oklahoma, EPA tracks 1,262 public water systems serving 3,699,452 people, with 336,706 cumulative violations and 113,804 health-based violations on record. About 98% of systems in the state carry at least one violation, and state-wide the average per system is 266.8 violations. Statewide, 101 of 166 UCMR5-tested systems have reported PFAS detections (60.8%).

Sequoyah Co. RWD #8's 199 violations sit below the Oklahoma average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
13,460
Total Violations
199
Health-Based Violations
31
Water Source
Surface Water

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

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

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Sequoyah Co. RWD #8.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID OK1020210 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Oklahoma Drinking Water Authority

Oklahoma's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.

Find OK regulator via EPA SDWIS

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2025 Chlorine MR 7 SDWIS / OK1020210 / 0999
2025 Revised Total Coliform Rule MON 7 SDWIS / OK1020210 / 8000
2024 LEAD AND COPPER RULE REVISIONS TT 1 SDWIS / OK1020210 / 5200
2024 LEAD AND COPPER RULE REVISIONS RPT 1 SDWIS / OK1020210 / 5200
2021 Surface Water Treatment Rule TT 12 SDWIS / OK1020210 / 0200
2020 1,2,4-Trichlorobenzene MR 4 SDWIS / OK1020210 / 2378
2020 cis-1,2-Dichloroethylene MR 4 SDWIS / OK1020210 / 2380
2020 Xylenes, Total MR 4 SDWIS / OK1020210 / 2955
2020 o-Dichlorobenzene MR 4 SDWIS / OK1020210 / 2968
2020 1,1-Dichloroethylene MR 4 SDWIS / OK1020210 / 2977
2020 1,1,1-Trichloroethane MR 4 SDWIS / OK1020210 / 2981
2020 Carbon tetrachloride MR 4 SDWIS / OK1020210 / 2982
2020 1,2-Dichloropropane MR 4 SDWIS / OK1020210 / 2983
2020 1,1,2-Trichloroethane MR 4 SDWIS / OK1020210 / 2985
2020 Tetrachloroethylene MR 4 SDWIS / OK1020210 / 2987

How Sequoyah Co. RWD #8 Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Sequoyah Co. RWD #8 Oklahoma avg Federal benchmark
Total violations 199 266.8 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 31 90.2 Indicates a contaminant exceeded a federal MCL
PFAS detection None 60.8% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 13,460 2,931 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 1,262 regulated public water systems in Oklahoma.

Federal MCL reference, Safe Drinking Water Act thresholds
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Sequoyah Co. RWD #8 water safe to drink?
Sequoyah Co. RWD #8 (PWS ID: OK1020210) has 199 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 13,460 people using Surface Water sources.
How many people does Sequoyah Co. RWD #8 serve?
Sequoyah Co. RWD #8 serves 13,460 people in Sallisaw, Oklahoma. It is a Local-owned system using Surface Water water sources with 5,386 service connections.
What type of violations does Sequoyah Co. RWD #8 have?
Sequoyah Co. RWD #8 has 199 total violations: 31 health-based violations (MCL exceedances or treatment failures), 135 monitoring/reporting violations, and 13 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Sequoyah Co. RWD #8 water?
No. Sequoyah Co. RWD #8 was tested for PFAS under the EPA's UCMR5 monitoring program and no PFAS contamination was detected.
What water source does Sequoyah Co. RWD #8 use?
Sequoyah Co. RWD #8 uses Surface Water as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from?
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
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.
Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.