1 open health-based violation on EPA record.
Serves about 914 people (30 connections) with groundwater from its own wells.
From EPA's record for CA3500581. PurityMap is independent of Rancho San Joaquin MWC.
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3 health-based violations in the last 10 years, from EPA's SDWIS compliance database.
| Period | Contaminant | Measured | Legal limit | EPA status |
|---|---|---|---|---|
| From October 2024 | Lead and copper rule revisions | – | – | Unaddressed |
| From July 2023 | Arsenic | 0.023 mg/L | 0.010 mg/L | Archived |
| From October 2022 | Arsenic | 0.011 mg/L | 0.010 mg/L | Archived |
No lab results for other contaminants (like PFAS) are on file for this system. EPA required that testing from systems serving more than 3,300 people, plus a sample of smaller ones.
Screening tells you if something is worth a closer look; a lab result is the number you can act on.
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Screening: quick check, not lab-grade
Safe Home (EnviroTestKits)
Lead, read as one of three ranges: 0–4, 5–15 or 15+ ppb
Turnaround: 5 minutes
What it can't tell you: It shows a lead range, not an exact level, and tests nothing else unless you pay extra for the optional lab test.
Lab-certified results
ETR Laboratories
50+ substances, including lead, copper, arsenic, nitrate, hardness and coliform bacteria
Environmental Testing and Research Laboratories (ETR Labs), Leominster, MA · ISO/IEC 17025:2017, ANAB certificate AT-2638 · 2–4 business days after the lab receives it
What it can't tell you: It does not test PFAS, and not every result on the panel falls under the lab's accredited scope.
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Follow this water →Rancho San Joaquin MWC's phone number on EPA record is 408-804-1401. Its mailing address is PO Box 1654, HOLLISTER, CA 95024.
According to EPA's record, Rancho San Joaquin MWC uses groundwater from its own wells.
EPA's record shows 3 health-based violations for Rancho San Joaquin MWC in the 10 years to July 9, 2026. EPA's record lists 1 open health-based violation. EPA also lists 7 missed or late tests or reports in 10 years. The record comes from EPA's SDWIS compliance database.
Lead was not detected at the 90th percentile of tap samples in Rancho San Joaquin MWC's latest lead and copper round, which ended in December 2024. The federal action level is 15 µg/L.
PurityMap has no verified website for Rancho San Joaquin MWC. Its phone number on EPA record is 408-804-1401. Its mailing address on EPA record is PO Box 1654, HOLLISTER, CA 95024. Your water bill lists the ways to contact your supplier and pay. PurityMap does not take payments.