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Transient Non-Community Water System · PWS AZ0411405

Biosphere II

Operator location Oracle, Arizona - smaller served population (≤ 999) at 221 people served; 125 SDWIS violations on record from groundwater sources.

221
People served (this PWS)
125
EPA violations (this PWS)
10
Health-based (this PWS)
Untested
UCMR5 (this PWS)
Follow published updates (RSS)

Biosphere II standing, high SDWIS violation third

221 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 8% is middle-third health share (≤ 23%).

The verdict

Biosphere II sits in the upper third of the sitemap cohort by violation count (125), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (221; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 8% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.

125
Total EPA violations on record
8%
Health-based (MCL / treatment failure)
221
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.

System Details

System Type
Transient Non-Community
Owner Type
Public/Private
Connections
65
County
Pinal
School/Daycare
No
MCL Violations
10
Monitoring Violations
106
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 17 2005
Coliform (TCR) MCL 10 2010
Nitrate MR 7 2004
Revised Total Coliform Rule MON 4 2022
1,2,4-Trichlorobenzene MR 2 2002
Xylenes, Total MR 2 2002
DICHLOROMETHANE MR 2 2002
o-Dichlorobenzene MR 2 2002
trans-1,2-Dichloroethylene MR 2 2002
1,1,1-Trichloroethane MR 2 2002
Carbon tetrachloride MR 2 2002
1,1,2-Trichloroethane MR 2 2002
Benzene MR 2 2002
Toluene MR 2 2002
Ethylbenzene MR 2 2002
Styrene MR 2 2002
cis-1,2-Dichloroethylene MR 2 2002
1,2-Dichloroethane MR 2 2002
Fluoride MR 2 1989
Mercury MR 2 1989
Arsenic MR 2 1989
Barium MR 2 1989
Cadmium MR 2 1989
Selenium MR 2 1989
Chromium MR 2 1989
1,1-Dichloroethylene MR 2 2002
Public Notice Other 2 2023
p-Dichlorobenzene MR 1 1998
CHLOROBENZENE MR 1 1998
Endrin MR 1 1998

Violation Count vs. the National Corpus

Biosphere II has 125 recorded EPA violations, 78% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 22% carry more. 8% of this system's own violations are health-based (10 of 125), 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)

125 Higher than most more violations than 78% 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

Population served record for Biosphere II

EPA SDWIS lists 221 people served and 65 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.

Sources: EPA SDWIS · Arizona DEQ, Drinking Water Program

Nationwide peers

125 violations · 221 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

What to do with Biosphere II

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

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