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Non-Transient Non-Community Water System · PWS IL3019638

Grass Lake School

Antioch, Illinois 60002 - drinking water served from groundwater sources to 300 people, tracked in EPA SDWIS and UCMR5.

300
People served
94
EPA violations
4
Health-based
Untested
UCMR5 result

The verdict

EPA records 94 drinking-water violations at Grass Lake School, 4% of them health-based - above the Illinois per-system average.

94
Total EPA violations on record
4%
Health-based (MCL / treatment failure)
300
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Grass Lake School

Grass Lake School is a local-owned non-transient non-community water system that delivers drinking water to 300 residents in Antioch, Illinois (Lake County) through 1 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 94 total violations for this system , of which 4 (4%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 86 monitoring and reporting violations are on file. The most recent violation on record dates to 2024.

The most frequently cited contaminant at this system is Lead and Copper Rule, recorded in 29 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across Illinois, EPA tracks 5,117 public water systems serving 12,576,876 people, with 355,322 cumulative violations and 52,932 health-based violations on record. About 81% of systems in the state carry at least one violation, and state-wide the average per system is 69.4 violations. Statewide, 123 of 487 UCMR5-tested systems have reported PFAS detections (25.3%).

Grass Lake School's 94 violations sit above the Illinois average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
300
Total Violations
94
Health-Based Violations
4
Water Source
Groundwater

System Details

System Type
Non-Transient Non-Community
Owner Type
Local
Connections
1
County
Lake
School/Daycare
Yes
MCL Violations
0
Monitoring Violations
86
Treatment Tech Violations
4

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Lead and Copper Rule MR 29 2022
Arsenic MR 15 2005
LEAD AND COPPER RULE REVISIONS RPT 4 2024
LEAD AND COPPER RULE REVISIONS TT 4 2024
Carbofuran MR 2 2002
BHC-GAMMA MR 2 2002
Atrazine MR 2 2002
2,4,5-TP MR 2 2002
Pentachlorophenol MR 2 2002
1,2-DIBROMO-3-CHLOROPROPANE MR 2 2002
ETHYLENE DIBROMIDE MR 2 2002
Chlordane MR 2 2002
Toxaphene MR 2 2002
Endothall MR 2 2002
Glyphosate MR 2 2002
Simazine MR 2 2002
Methoxychlor MR 2 2002
Heptachlor epoxide MR 2 2002
LASSO MR 2 2002
Diquat MR 2 2002
Picloram MR 2 2002
Heptachlor MR 2 2002
OXAMYL MR 2 2002
Total Polychlorinated Biphenyls (PCB) MR 2 2002
2,4-D MR 2 2002

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Grass Lake School.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID IL3019638 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Illinois Drinking Water Authority

Illinois EPA, Bureau of Water is the primacy agency that licenses and inspects Grass Lake School under EPA-delegated authority.

Open IL regulator portal

Source: Illinois EPA, Bureau of Water

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2024 LEAD AND COPPER RULE REVISIONS RPT 4 SDWIS / IL3019638 / 5200
2024 LEAD AND COPPER RULE REVISIONS TT 4 SDWIS / IL3019638 / 5200
2022 Lead and Copper Rule MR 29 SDWIS / IL3019638 / 5000
2005 Arsenic MR 15 SDWIS / IL3019638 / 1005
2002 Carbofuran MR 2 SDWIS / IL3019638 / 2046
2002 BHC-GAMMA MR 2 SDWIS / IL3019638 / 2010
2002 Atrazine MR 2 SDWIS / IL3019638 / 2050
2002 2,4,5-TP MR 2 SDWIS / IL3019638 / 2110
2002 Pentachlorophenol MR 2 SDWIS / IL3019638 / 2326
2002 1,2-DIBROMO-3-CHLOROPROPANE MR 2 SDWIS / IL3019638 / 2931
2002 ETHYLENE DIBROMIDE MR 2 SDWIS / IL3019638 / 2946
2002 Chlordane MR 2 SDWIS / IL3019638 / 2959
2002 Toxaphene MR 2 SDWIS / IL3019638 / 2020
2002 Endothall MR 2 SDWIS / IL3019638 / 2033
2002 Glyphosate MR 2 SDWIS / IL3019638 / 2034

How Grass Lake School Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Grass Lake School Illinois avg Federal benchmark
Total violations 94 69.4 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 4 10.3 Indicates a contaminant exceeded a federal MCL
PFAS detection None 25.3% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 300 2,458 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 5,117 regulated public water systems in Illinois.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Grass Lake School water safe to drink? ▼
Grass Lake School (PWS ID: IL3019638) has 94 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 300 people using Groundwater sources.
How many people does Grass Lake School serve? ▼
Grass Lake School serves 300 people in Antioch, Illinois. It is a Local-owned system using Groundwater water sources with 1 service connections.
What type of violations does Grass Lake School have? ▼
Grass Lake School has 94 total violations: 4 health-based violations (MCL exceedances or treatment failures), 86 monitoring/reporting violations, and 4 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Grass Lake School water? ▼
No PFAS testing data is available for Grass Lake School under the EPA's UCMR5 monitoring program.
What water source does Grass Lake School use? ▼
Grass Lake School uses Groundwater as its primary water source. It is classified as a Non-Transient Non-Community Water System, serving the same people for at least 6 months per year.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.