IL0315185 · Illinois
OASIS MHP
Federal fiscal 2026Q3 · EPA violation and follow-up records
- Violation records shown
- 12
- EPA health-based flag
- 0
- Health-based records unresolved in this snapshot
- 0
- Monitoring and reporting records
- 12
Counties listed by EPA · Cook County, Illinois
Find the utility’s annual water quality report. For current advisories, check the utility or local drinking-water authority.
Violations and what followed
Among 11 resolved records with both dates, the median interval from recorded noncompliance start to EPA’s return-to-compliance date was 1,095 days. The interval uses the reporting periods and dates on file.
Monitoring or reporting · Resolved
Monitoring and Reporting (DBP)Violation 3790410 · Total Haloacetic Acids (HAA5) · Stage 2 Disinfectants and Disinfection Byproducts RuleNoncompliance period start September 1, 2021 · period end August 31, 2022 · first reported November 10, 2022 · EPA return-to-compliance field August 31, 2022
4 linked actions
Enforcement and resolution records linked by EPA Action ID Date Category EPA action type 6498305 October 17, 2022 Informal State Violation/Reminder Notice 6498306 October 17, 2022 Informal State Public Notification requested 6498334 May 22, 2023 Informal State Public Notification received 6498332 September 8, 2023 Resolving State Compliance achieved Monitoring or reporting · Resolved
Monitoring and Reporting (DBP)Violation 3790409 · TTHM · Stage 2 Disinfectants and Disinfection Byproducts RuleNoncompliance period start September 1, 2021 · period end August 31, 2022 · first reported November 10, 2022 · EPA return-to-compliance field August 31, 2022
4 linked actions
Enforcement and resolution records linked by EPA Action ID Date Category EPA action type 6498305 October 17, 2022 Informal State Violation/Reminder Notice 6498306 October 17, 2022 Informal State Public Notification requested 6498334 May 22, 2023 Informal State Public Notification received 6498332 September 8, 2023 Resolving State Compliance achieved Monitoring or reporting · Resolved
Monitoring, RegularViolation 3790422 · Total Polychlorinated Biphenyls (PCB) · Synthetic Organic ChemicalsNoncompliance period start January 1, 2020 · period end December 31, 2022 · first reported February 28, 2023 · EPA return-to-compliance field December 31, 2022
4 linked actions
Enforcement and resolution records linked by EPA Action ID Date Category EPA action type 6498329 February 8, 2023 Informal State Violation/Reminder Notice 6498330 February 8, 2023 Informal State Public Notification requested 6498333 May 22, 2023 Informal State Public Notification received 6498331 June 23, 2023 Resolving State Compliance achieved Monitoring or reporting · Resolved
Monitoring, RegularViolation 3790421 · Mercury · Inorganic ChemicalsNoncompliance period start January 1, 2020 · period end December 31, 2022 · first reported February 28, 2023 · EPA return-to-compliance field December 31, 2022
4 linked actions
Enforcement and resolution records linked by EPA Action ID Date Category EPA action type 6498327 February 7, 2023 Informal State Violation/Reminder Notice 6498328 February 7, 2023 Informal State Public Notification requested 6498338 May 22, 2023 Informal State Public Notification received 6498346 February 2, 2024 Resolving State Compliance achieved Monitoring or reporting · Resolved
Monitoring, RegularViolation 3790420 · Barium · Inorganic ChemicalsNoncompliance period start January 1, 2020 · period end December 31, 2022 · first reported February 28, 2023 · EPA return-to-compliance field December 31, 2022
4 linked actions
Enforcement and resolution records linked by EPA Action ID Date Category EPA action type 6498325 February 7, 2023 Informal State Violation/Reminder Notice 6498326 February 7, 2023 Informal State Public Notification requested 6498335 May 22, 2023 Informal State Public Notification received 6498346 February 2, 2024 Resolving State Compliance achieved Monitoring or reporting · Resolved
Monitoring, RegularViolation 3790419 · Selenium · Inorganic ChemicalsNoncompliance period start January 1, 2020 · period end December 31, 2022 · first reported February 28, 2023 · EPA return-to-compliance field December 31, 2022
4 linked actions
Enforcement and resolution records linked by EPA Action ID Date Category EPA action type 6498323 February 7, 2023 Informal State Violation/Reminder Notice 6498324 February 7, 2023 Informal State Public Notification requested 6498340 May 22, 2023 Informal State Public Notification received 6498346 February 2, 2024 Resolving State Compliance achieved Monitoring or reporting · Resolved
Monitoring, RegularViolation 3790418 · Nickel · Inorganic ChemicalsNoncompliance period start January 1, 2020 · period end December 31, 2022 · first reported February 28, 2023 · EPA return-to-compliance field December 31, 2022
4 linked actions
Enforcement and resolution records linked by EPA Action ID Date Category EPA action type 6498321 February 7, 2023 Informal State Violation/Reminder Notice 6498322 February 7, 2023 Informal State Public Notification requested 6498339 May 22, 2023 Informal State Public Notification received 6498346 February 2, 2024 Resolving State Compliance achieved Monitoring or reporting · Resolved
Monitoring, RegularViolation 3790417 · Beryllium, Total · Inorganic ChemicalsNoncompliance period start January 1, 2020 · period end December 31, 2022 · first reported February 28, 2023 · EPA return-to-compliance field December 31, 2022
4 linked actions
Enforcement and resolution records linked by EPA Action ID Date Category EPA action type 6498319 February 7, 2023 Informal State Violation/Reminder Notice 6498320 February 7, 2023 Informal State Public Notification requested 6498343 May 22, 2023 Informal State Public Notification received 6498346 February 2, 2024 Resolving State Compliance achieved Monitoring or reporting · Resolved
Monitoring, RegularViolation 3790416 · Thallium, Total · Inorganic ChemicalsNoncompliance period start January 1, 2020 · period end December 31, 2022 · first reported February 28, 2023 · EPA return-to-compliance field December 31, 2022
4 linked actions
Enforcement and resolution records linked by EPA Action ID Date Category EPA action type 6498317 February 7, 2023 Informal State Violation/Reminder Notice 6498318 February 7, 2023 Informal State Public Notification requested 6498344 May 22, 2023 Informal State Public Notification received 6498346 February 2, 2024 Resolving State Compliance achieved Monitoring or reporting · Resolved
Monitoring, RegularViolation 3790414 · Cadmium · Inorganic ChemicalsNoncompliance period start January 1, 2020 · period end December 31, 2022 · first reported February 28, 2023 · EPA return-to-compliance field December 31, 2022
4 linked actions
Enforcement and resolution records linked by EPA Action ID Date Category EPA action type 6498313 February 7, 2023 Informal State Violation/Reminder Notice 6498314 February 7, 2023 Informal State Public Notification requested 6498336 May 22, 2023 Informal State Public Notification received 6498346 February 2, 2024 Resolving State Compliance achieved Monitoring or reporting · Resolved
Monitoring, RegularViolation 3790411 · Antimony, Total · Inorganic ChemicalsNoncompliance period start January 1, 2020 · period end December 31, 2022 · first reported February 28, 2023 · EPA return-to-compliance field December 31, 2022
4 linked actions
Enforcement and resolution records linked by EPA Action ID Date Category EPA action type 6498307 February 7, 2023 Informal State Violation/Reminder Notice 6498308 February 7, 2023 Informal State Public Notification requested 6498342 May 22, 2023 Informal State Public Notification received 6498346 February 2, 2024 Resolving State Compliance achieved Monitoring or reporting · Archived
Monitoring, RegularViolation 3790427 · Combined Radium (-226 and -228) · Radionuclides and Revised Rad RuleNoncompliance period start January 1, 2017 · period end December 31, 2025 · first reported February 26, 2026 · EPA return-to-compliance field December 31, 2025
3 linked actions
Enforcement and resolution records linked by EPA Action ID Date Category EPA action type 6498357 January 14, 2026 Informal State Violation/Reminder Notice 6498358 January 14, 2026 Informal State Public Notification requested 6498363 April 14, 2026 Informal State Public Notification received
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