Contaminant 5000
Unresolved Phase I/II/V Inorganic Chemical Rules violation cited in 2025 (contaminant 5000).
PWSID AZ0409091 · GroundwaterPrivate
75 people served. 2 health-based SDWIS violations recorded in the past 5 years. 5 remain unresolved. Last cited 1 year ago.
Unresolved Phase I/II/V Inorganic Chemical Rules violation cited in 2025 (contaminant 5000).
Unresolved Revised Total Coliform Rule violation cited in 2025 (contaminant 8000).
Unresolved Revised Total Coliform Rule violation cited in 2025 (contaminant 8000).
Unresolved Revised Total Coliform Rule violation cited in 2024 (contaminant 8000).
Health-based violations exceed an MCL or treatment-technique standard. Monitoring violations are reporting failures with no measured exceedance — they tell you the system isn't fully transparent, not that the water is unsafe today.
Failure to monitor as scheduled
OTHER; returned to compliance
Monitoring failure
Monitoring failure; returned to compliance
Monitoring failure
Monitoring failure; returned to compliance
Monitoring failure
Monitoring failure; returned to compliance
Monitoring failure; returned to compliance
Monitoring failure
Monitoring failure; returned to compliance
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled; returned to compliance
Reporting failure; returned to compliance
Reporting failure; returned to compliance
Treatment technique violation; returned to compliance
Treatment technique violation; returned to compliance
Monitoring failure; returned to compliance
Tucson, Arizona (Census place; block-group disparity scores aggregated by centroid containment): a service population of 541,033. Local disparity score for pm2.5 (fine particulate) sits well below the reference (12). Why we surface this →
Low-income
People of color
Under age 5
Over age 64
| Indicator | Disparity score | Reading |
|---|---|---|
| PM2.5 (fine particulate) | 12 | well below the reference |
| Ozone | 176 | well above the reference burden |
| Nitrogen dioxide (NO₂) | 147 | moderately above the reference |
| Diesel particulate | 135 | moderately above the reference |
| Toxic releases (RSEI) | 96 | near the reference |
| Traffic proximity | 138 | moderately above the reference |
| Lead-paint risk (pre-1960 housing) | 76 | below the reference |
| Superfund site proximity | 94 | near the reference |
| RMP-facility proximity | 87 | below the reference |
| Hazardous-waste site proximity | 98 | near the reference |
| Underground storage tanks | 108 | near the reference |
| NPDES wastewater proximity | 157 | well above the reference burden |
| Drinking-water non-compliance | 2 | well below the reference |
Source: Census ACS 2018-2022 (5-year) + USEPA-clone EJ blockgroup stats (raw indicators + EJ disparity mirror).
Source. EPA Safe Drinking Water Information System · retrieved 2026-05-07. Reporting period 2021-01-01 → 2026-05-07.
What this is not. SDWIS records compliance against federal MCLs — not a direct readout of tap-water concentrations. Active health-based violations are not the same as a current crisis; we link to the EPA record so you can verify return-to-compliance status before forming a conclusion.