CA0706004 · California

OAKLEY MUTUAL WATER COMPANY

Federal fiscal 2026Q3 · EPA violation and follow-up records

Violation records shown: 20
EPA health-based flag: 19
Health-based records unresolved in this snapshot: 1
Monitoring and reporting records: 1

Counties listed by EPA · Contra Costa County, California

Find the utility’s annual water quality report. For current advisories, check the utility or local drinking-water authority.

Violations and what followed

EPA health-based flag · Unaddressed by formal action
LSL InventoryViolation 1300016 · LEAD AND COPPER RULE REVISIONS · Lead and Copper Rule Revisions
Noncompliance period start October 17, 2024 · first reported April 1, 2025
No linked action row appears in the records shown.
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300022 · Arsenic · Arsenic Rule
Noncompliance period start January 1, 2026 · period end March 31, 2026 · first reported June 22, 2026 · EPA return-to-compliance field March 31, 2026

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300021 · Arsenic · Arsenic Rule
Noncompliance period start October 1, 2025 · period end December 31, 2025 · first reported March 20, 2026 · EPA return-to-compliance field December 31, 2025

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300020 · Arsenic · Arsenic Rule
Noncompliance period start July 1, 2025 · period end September 30, 2025 · first reported March 20, 2026 · EPA return-to-compliance field September 30, 2025

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300019 · Arsenic · Arsenic Rule
Noncompliance period start April 1, 2025 · period end June 30, 2025 · first reported March 20, 2026 · EPA return-to-compliance field June 30, 2025

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300018 · Arsenic · Arsenic Rule
Noncompliance period start January 1, 2025 · period end March 31, 2025 · first reported March 20, 2026 · EPA return-to-compliance field March 31, 2025

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
Monitoring or reporting · Unaddressed by formal action
LSL ReportingViolation 1300017 · LEAD AND COPPER RULE REVISIONS · Lead and Copper Rule Revisions
Noncompliance period start October 17, 2024 · first reported April 1, 2025
No linked action row appears in the records shown.
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300015 · Arsenic · Arsenic Rule
Noncompliance period start October 1, 2024 · period end December 31, 2024 · first reported February 24, 2025 · EPA return-to-compliance field December 31, 2024

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300014 · Arsenic · Arsenic Rule
Noncompliance period start July 1, 2024 · period end September 30, 2024 · first reported November 15, 2024 · EPA return-to-compliance field September 30, 2024

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300013 · Arsenic · Arsenic Rule
Noncompliance period start April 1, 2024 · period end June 30, 2024 · first reported November 15, 2024 · EPA return-to-compliance field June 30, 2024

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300012 · Arsenic · Arsenic Rule
Noncompliance period start January 1, 2024 · period end March 31, 2024 · first reported November 15, 2024 · EPA return-to-compliance field March 31, 2024

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300011 · Arsenic · Arsenic Rule
Noncompliance period start October 1, 2023 · period end December 31, 2023 · first reported February 15, 2024 · EPA return-to-compliance field December 31, 2023

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300010 · Arsenic · Arsenic Rule
Noncompliance period start July 1, 2023 · period end September 30, 2023 · first reported November 15, 2023 · EPA return-to-compliance field September 30, 2023

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300009 · Arsenic · Arsenic Rule
Noncompliance period start April 1, 2023 · period end June 30, 2023 · first reported August 16, 2023 · EPA return-to-compliance field June 30, 2023

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300008 · Arsenic · Arsenic Rule
Noncompliance period start January 1, 2023 · period end March 31, 2023 · first reported March 31, 2023 · EPA return-to-compliance field March 31, 2023

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300007 · Arsenic · Arsenic Rule
Noncompliance period start October 1, 2022 · period end December 31, 2022 · first reported February 16, 2023 · EPA return-to-compliance field December 31, 2022

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300006 · Arsenic · Arsenic Rule
Noncompliance period start July 1, 2022 · period end September 30, 2022 · first reported November 17, 2022 · EPA return-to-compliance field September 30, 2022

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300005 · Arsenic · Arsenic Rule
Noncompliance period start April 1, 2022 · period end June 30, 2022 · first reported November 17, 2022 · EPA return-to-compliance field June 30, 2022

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300004 · Arsenic · Arsenic Rule
Noncompliance period start January 1, 2022 · period end March 31, 2022 · first reported March 31, 2022 · EPA return-to-compliance field March 31, 2022

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued
EPA health-based flag · Archived
Maximum Contaminant Level Violation, AverageViolation 1300003 · Arsenic · Arsenic Rule
Noncompliance period start October 1, 2021 · period end December 31, 2021 · first reported February 16, 2022 · EPA return-to-compliance field December 31, 2021

1 linked action

Enforcement and resolution records linked by EPA
Action ID Date Category EPA action type
1300328 December 10, 2021 Formal State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1300328	December 10, 2021	Formal	State Administrative/Compliance Order without penalty issued

EPA data and scope

How to read the records

The enforcement snapshot is federal fiscal 2026Q3. The EPA archive labels its violation file October 13, 2026. EPA says federal reporting can lag by several months. For current advisories, check your utility or local drinking-water authority.

We matched active community water systems by public water system ID between EPA’s system search and SDWIS inventory. We show violations with a recorded noncompliance, initial reporting or return-to-compliance date from 2021 onward, plus earlier records listed as Addressed or Unaddressed.
EPA’s health-based flag identifies violations of contaminant or disinfectant limits or treatment requirements. Monitoring and reporting violations describe required tests or reports. Neither category measures household exposure.
Addressed means EPA records formal enforcement on a violation that remains unresolved in the snapshot. Unaddressed means no formal action is recorded for an unresolved violation. Resolved can mean compliance was restored, the rule ceased to apply, or further action was unnecessary. Archived is a separate status.
We count a violation once per water system and group its distinct linked actions. Conflicting records are set aside. Places are EPA-listed search locations and can include mailing locations. Use the provider name and system ID to identify your service.

EPA data dictionary and files · EPA reporting and enforcement FAQ · Find an annual water quality report · How to get the report from your utility