Arsenic
Unresolved Phase I/II/V Inorganic Chemical Rules violation cited in 2023 (arsenic).
PWSID WA5338900 · Surface waterMunicipal
3,723 people served. 2 health-based SDWIS violations recorded in the past 5 years. 28 remain unresolved. Last cited 1 year ago.
Unresolved Phase I/II/V Inorganic Chemical Rules violation cited in 2023 (arsenic).
Unresolved Lead and Copper Rule violation cited in 2020 (contaminant 2210).
Unresolved Lead and Copper Rule violation cited in 2020 (contaminant 2214).
Unresolved Lead and Copper Rule violation cited in 2020 (contaminant 2216).
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.
Treatment technique violation; returned to compliance
Failure to monitor as scheduled
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled; returned to compliance
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Failure to monitor as scheduled
Maximum contaminant level exceeded; returned to compliance
Vashon, Washington (Census place; block-group disparity scores aggregated by centroid containment): a service population of 10,939. Local disparity score for pm2.5 (fine particulate) sits well below the reference (37). Why we surface this →
Low-income
People of color
Under age 5
Over age 64
| Indicator | Disparity score | Reading |
|---|---|---|
| PM2.5 (fine particulate) | 37 | well below the reference |
| Ozone | 2 | well below the reference |
| Nitrogen dioxide (NO₂) | 5 | well below the reference |
| Diesel particulate | 40 | well below the reference |
| Toxic releases (RSEI) | 39 | well below the reference |
| Traffic proximity | 15 | well below the reference |
| Lead-paint risk (pre-1960 housing) | 37 | well below the reference |
| Superfund site proximity | 36 | well below the reference |
| RMP-facility proximity | 14 | well below the reference |
| Hazardous-waste site proximity | 14 | well below the reference |
| Underground storage tanks | 25 | well below the reference |
| NPDES wastewater proximity | 4 | well below the reference |
| Drinking-water non-compliance | 33 | 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 2020-01-01 → 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.