Non-Transient Non-Community Water System · PWS 105338123
San Poil
Operator location Nespelem, EPA Region 10 — Tribal Water Systems - 0% of 57 violations are health-based (lower-third health share (≤ 1%)); groundwater source; 86 served per SDWIS.
- 86
- People served (this PWS) Smaller third of systems
- 57
- EPA violations (this PWS) Middle third of systems
- 0
- Health-based (this PWS) Lower third by health-based share
- Untested
- UCMR5 (this PWS) No UCMR5 result
San Poil standing, mid SDWIS violation third
0% of 57 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%).
The verdict
San Poil lands in the middle third by violation volume (57), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is smaller (86; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is only 0% - almost all of this trail is monitoring or reporting. No UCMR5 PFAS test appears for this system in this extract.
- 57
- Total EPA violations on record
- 0%
- Health-based (MCL / treatment failure)
- 86
- People served by this PWS (SDWIS)
- N/A
- PFAS compounds detected (UCMR5)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
Based on EPA SDWIS violation history and UCMR5 PFAS testing only, not water taste, odor, infrastructure age, or contaminants outside the federally tracked set.
System Details
- System Type
- Non-Transient Non-Community
- Owner Type
- Native American
- Connections
- 1
- School/Daycare
- No
- MCL Violations
- 0
- Monitoring Violations
- 57
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| 2,3,7,8-TCDD | MR | 2 | 2025 |
| Revised Total Coliform Rule | MON | 2 | 2025 |
| Toxaphene | MR | 1 | 2025 |
| Methoxychlor | MR | 1 | 2025 |
| Hexachlorocyclopentadiene | MR | 1 | 2025 |
| Atrazine | MR | 1 | 2025 |
| Heptachlor | MR | 1 | 2025 |
| TTHM | MR | 1 | 2025 |
| Di(2-ethylhexyl) phthalate | MR | 1 | 2025 |
| 1,2-Dichloropropane | MR | 1 | 2025 |
| Total Haloacetic Acids (HAA5) | MR | 1 | 2025 |
| Carbon tetrachloride | MR | 1 | 2025 |
| Total Polychlorinated Biphenyls (PCB) | MR | 1 | 2025 |
| 1,1,2-Trichloroethane | MR | 1 | 2025 |
| Di(2-ethylhexyl) adipate | MR | 1 | 2025 |
| cis-1,2-Dichloroethylene | MR | 1 | 2025 |
| trans-1,2-Dichloroethylene | MR | 1 | 2025 |
| Chlordane | MR | 1 | 2025 |
| Pentachlorophenol | MR | 1 | 2025 |
| o-Dichlorobenzene | MR | 1 | 2025 |
| 2,4,5-TP | MR | 1 | 2025 |
| Ethylbenzene | MR | 1 | 2025 |
| HEXACHLOROBENZENE | MR | 1 | 2025 |
| Simazine | MR | 1 | 2025 |
| Benzene | MR | 1 | 2025 |
| Endrin | MR | 1 | 2025 |
| Benzo(a)pyrene | MR | 1 | 2025 |
| Tetrachloroethylene | MR | 1 | 2025 |
| ETHYLENE DIBROMIDE | MR | 1 | 2025 |
| CHLOROBENZENE | MR | 1 | 2025 |
Violation Count vs. the National Corpus
San Poil has 57 recorded EPA violations, 60% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 40% carry more. 0% of this system's own violations are health-based (0 of 57), and it ranks unranked by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
57 Around the middle fewer violations than 40% 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
How many violations vs. how serious, among peer systems
San Poil plotted against 29 peer public water systems (500+ people served), by total violation count (x) and the share of those violations that are health-based (y). The crosshair sits at this sample's own median on each axis. A high violation count does not automatically mean a serious record: most monitoring and reporting violations are minor, not health-based.
Violation volume vs. health-based share
Health-based violations on San Poil
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 105338123.
Sources: EPA SDWIS
Nationwide peers
57 violations · 86 served: nearest cross-state SDWIS matches.
Cross-state systems near this violation count
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
What to do with San Poil
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in EPA Region 10 — Tribal Water Systems compares on the same EPA violation measures. EPA Region 10 — Tribal Water Systems 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.
Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.