PlainWater

Community Water System · PWS NN0433016

Shonto Preparatory Boarding School BIA

Operator location Shonto, Navajo Nation - 0% of 106 violations are health-based (lower-third health share (≤ 1%)); groundwater source; 664 served per SDWIS.

664
People served (this PWS)
106
EPA violations (this PWS)
0
Health-based (this PWS)
Untested
UCMR5 (this PWS)
Follow published updates (RSS)

Shonto Preparatory Boarding School BIA standing, high SDWIS violation third

0% of 106 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%). Population rank #24,959 of 29,740 among systems serving 500+.

The verdict

Shonto Preparatory Boarding School BIA sits in the upper third of the sitemap cohort by violation count (106), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (664; 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.

#24,959 of 29,740
Population · /systems
#74 of 82
Population · NN
106
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
Federal
Connections
166
School/Daycare
Yes
MCL Violations
0
Monitoring Violations
82
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
2,3,7,8-TCDD MR 5 2008
Coliform (TCR) MR 5 2014
Revised Total Coliform Rule RPT 4 2024
Consumer Confidence Rule Other 4 2006
Stage 2 Disinfectants and Disinfection Byproducts Rule MR 3 2013
Revised Total Coliform Rule Other 3 2016
E. COLI MR 2 2018
Arsenic MR 1 2008
Barium MR 1 2008
Cadmium MR 1 2008
Fluoride MR 1 2008
Selenium MR 1 2008
Thallium, Total MR 1 2008
Endrin MR 1 2004
Methoxychlor MR 1 2004
Toxaphene MR 1 2004
Diquat MR 1 2004
Endothall MR 1 2004
Glyphosate MR 1 2004
Di(2-ethylhexyl) adipate MR 1 2004
OXAMYL MR 1 2004
Di(2-ethylhexyl) phthalate MR 1 2004
Hexachlorocyclopentadiene MR 1 2004
Aldicarb sulfoxide MR 1 2004
Aldicarb sulfone MR 1 2004
Aldicarb MR 1 2004
Heptachlor MR 1 2004
2,4-D MR 1 2004
2,4,5-TP MR 1 2004
Benzo(a)pyrene MR 1 2004

Violation Count vs. the National Corpus

Shonto Preparatory Boarding School BIA has 106 recorded EPA violations, 74% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 25% carry more. 0% of this system's own violations are health-based (0 of 106), and it ranks #24,959 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)

106 Around the middle fewer violations than 25% 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

Health-based violations on Shonto Preparatory Boarding School BIA

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 NN0433016.

Sources: EPA SDWIS

Nationwide peers

106 violations · 664 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 smaller service footprints

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

4 peers

What to do with Shonto Preparatory Boarding School BIA

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

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