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Water Quality Technical Report — WEST DUNDEE, IL

PWSID
IL0890950
Population
7,845
Source
Groundwater
Data Period
—
Last Updated

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Summary

WEST DUNDEE serves approximately 7,845 people in WEST DUNDEE, Illinois. Based on contaminant analyses from DNR, WQP, EPA ECHO, EPA UCMR5, 0 contaminants have been measured above federal EPA standards (MCL) and 2 exceed health-based guidelines. The most significant finding is Lead (90th Percentile) at 0.008 mg/L, which is 40x the health guideline. Data is drawn from source-level compliance monitoring and covers 1996 through 2026. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.

Key Findings

Understanding the two thresholds

EPA Legal Limit (MCL)

The highest level of a contaminant allowed by federal law. Utilities that exceed this threshold face enforcement action. Limits balance health risk against the cost of treatment, so they are not always set at levels considered safe by independent researchers.

Health Guideline

The level below which independent researchers (CalEPA, WHO, EWG) believe there is no known health risk. Guidelines are not legally enforceable but are typically stricter than legal limits — often by 10x or more for contaminants like arsenic and lead.

A reading can be below the EPA limit (legally compliant) while still exceeding health guidelines (above levels considered safe by independent researchers).

Exceeds Health Guidelines

These contaminants were detected below the EPA legal limit but above a health-based guideline from a public health agency (CalEPA OEHHA, WHO, or similar). Health guidelines are non-enforceable research-backed targets that are often stricter than the legal limit.

Detected contaminants
ContaminantResultUnitHealth GuidelineEPA Legal LimitSourceSample Date
Lead (90th Percentile)
Developmental delays in children, kidney damage, high blood pressure. There is no safe level of lead exposure.
8ug/L0.215
Pending rule: LCRI 2024 — Action level drops from 15 → 10 µg/L effective 2027; full lead service line replacement within 10 years (EPA Lead & Copper Rule Improvements, October 2024)
EPA ECHO
Barium
Increase in blood pressure
1mg/L12DNR

Microplastics

Microplastics have been documented in raw and treated drinking water worldwide, but federal regulations do not currently require testing — so there is no data specific to this system. Standardized methods and rules are in progress.

Other Regulated Contaminants

These contaminants were detected within federal standards (EPA Maximum Contaminant Levels). They are presented for transparency.

Detected contaminants
ContaminantResultUnitHealth GuidelineEPA Legal LimitSourceSample Date
Total Trihalomethanes (TTHMs)
Single sample — not a compliance determination (Stage 2 DBPR requires a Locational Running Annual Average across 4 quarters; N=2 available).
Liver, kidney, or central nervous system problems; increased risk of cancer
71ug/L0.1580DNR
Haloacetic Acids (HAA5)
Single sample — not a compliance determination (Stage 2 DBPR requires a Locational Running Annual Average across 4 quarters; N=2 available).
Increased risk of cancer
20ug/L0.160DNR
Fluoride (natural)
Bone disease, mottled teeth in children
632ug/L40004000DNR
Combined Radium (226+228)
Increased risk of cancer
2.36pCi/L05DNR
Gross Alpha
Increased risk of cancer
5.1pCi/L015DNR
Nitrate (as N)
Blue baby syndrome in infants
46ug/L1000010000(as N)WQP(5+ years ago)
Arsenic
Skin damage, circulatory problems, increased risk of cancer
150ng/L410000WQP(5+ years ago)
Chromium (total)
Note: total chromium includes the harmless trivalent form (Cr-III). The toxic hexavalent form (Cr-VI) has no federal MCL; California set a 10 µg/L Cr-VI MCL in 2014.
Allergic dermatitis
1.2ug/L100100WQP(5+ years ago)

Unregulated Detected Contaminants

These contaminants were detected but do not have a federal Maximum Contaminant Level. They are monitored for awareness, not compliance.

Other Substances

Detected contaminants
ContaminantResultUnitHealth GuidelineEPA Legal LimitSourceSample Date
Copper (90th Percentile)
Gastrointestinal distress at high levels. Long-term exposure can cause liver or kidney damage.
Per-source breakdown (51 sampling locations)
  • Sampling locationMost recent valueSample date
  • Well LC1T068250 ug/L9/2/26
  • Well LC1T028250 ug/L12/5/25
  • Well LC1T066240 ug/L9/2/26
  • Well LC5T040190 ug/L11/18/25
  • Well LC5T015190 ug/L9/24/25
  • Well LC1T057180 ug/L8/26/26
  • Well LC1T071170 ug/L9/2/26
  • Well LC5T037170 ug/L9/20/25
  • Well LC1T060160 ug/L9/2/26
  • Well LC1T054160 ug/L8/29/26
  • Well LC1T052150 ug/L9/2/26
  • Well LC1T065150 ug/L9/2/26
  • Well LC5T021150 ug/L12/4/25
  • Well LC5T006150 ug/L11/19/25
  • Well LC5T017150 ug/L9/17/25
  • Well LC1T056140 ug/L8/28/26
  • Well LC1T062140 ug/L8/26/26
  • Well LC1T067130 ug/L9/2/26
  • Well LC1T069130 ug/L8/25/26
  • Well LC1T022130 ug/L11/20/25
  • Well LC5T032130 ug/L9/18/25
  • Well LC1T034120 ug/L12/10/25
  • Well LC5T047120 ug/L9/23/25
  • Well LC5T013110 ug/L9/16/25
  • Well LC1T064100 ug/L9/2/26
  • Well LC5T004100 ug/L10/4/25
  • Well LC5T00897 ug/L12/4/25
  • Well LC5T01994 ug/L11/18/25
  • Well LC1T03593 ug/L9/5/25
  • Well LC1T02690 ug/L12/9/25
  • Well LC1T07087 ug/L9/2/26
  • Well LC5T03384 ug/L11/26/25
  • Well LC1T06383 ug/L9/7/26
  • Well LC5T03883 ug/L11/20/25
  • Well LC1T06177 ug/L8/26/26
  • Well LC5T00770 ug/L12/4/25
  • Well LC5T01164 ug/L11/18/25
  • Well LC5T01059 ug/L11/19/25
  • Well LC5T04250 ug/L11/18/25
  • Well LC1T02532 ug/L12/5/25
  • Well LC5T03031 ug/L11/23/25
  • Well LC5T02931 ug/L9/24/25
  • Well LC5T05027 ug/L12/16/25
  • Well LC5T02023 ug/L12/2/25
  • Well LC5T01620 ug/L9/15/25
  • Well LC5T02419 ug/L11/19/25
  • Well LC1T05314 ug/L9/2/26
  • Well LC5T05113 ug/L12/10/25
  • Well LC5T01213 ug/L11/17/25
  • Well LC1T0597.3 ug/L8/25/26
  • Well LC1T0554.3 ug/L8/26/26
83ug/L3001300DNR

Other Potential Contaminants

Not detecting a contaminant does not prove it isn't present — it only means the laboratory didn't test for it, or tested below the reporting limit. Many substances of emerging concern are not routinely monitored because federal regulations haven't caught up to the science.

Compliance History

Formal EPA and DNR compliance events on record for this utility. Includes all events from the last 10 years plus any unresolved violations regardless of age. Health-based violations are legally enforceable thresholds that were exceeded; procedural events are monitoring or reporting lapses that don't indicate contamination by themselves.

No EPA compliance events on record for this utility.

Source: EPA ECHO enforcement and violation records (via Envirofacts / SDWIS Federal Reports).

Action Steps

This system has contaminants above a legal limit or multiple health guidelines. The following steps are concrete things a homeowner or facility operator can do right now — starting with the most important non-commercial options.

  1. Request the utility's Consumer Confidence Report (CCR). The CCR compares utility-reported readings to the federal legal limits and is independent of this site. Utilities must make it available on request. EPA CCR search.
  2. Get a certified tap test. A state-certified laboratory can test your tap for a specific contaminant or a broader panel. A single-contaminant test runs in the low tens of dollars; a comprehensive panel runs several hundred. Ask for the EPA-certified lab list from the Illinois drinking water program. State lab certification programs.
  3. Consider point-of-use filtration. For the specific contaminants detected in this system, the exceedance sections above list the technology categories (reverse osmosis, granular activated carbon, ion exchange, etc.) that target each class. Those are category-level descriptions — the right choice depends on the contaminant profile, budget, and installation constraints.
  4. Contact the utility directly. Ask about the specific contaminants you're concerned about and request the most recent sampling data. The EPA SDWIS portal lists utility contact details. EPA SDWIS system lookup.
  5. Check the utility's lead service line inventory. Under the Lead and Copper Rule Revisions (LCRR, 2024), utilities must publish a service line inventory identifying lines flagged as lead, galvanized-requiring-replacement, or unknown material. If your service line is flagged or unknown, the utility is required to replace it on a scheduled timeline. EPA Lead and Copper Rule Improvements.

Frequently Asked Questions

What contaminants are in WEST DUNDEE water?

Based on available public monitoring data, 38 contaminants have been tested in WEST DUNDEE's water supply. 8 were detected above reporting limits. The most notable detections include Total Trihalomethanes (TTHMs), Haloacetic Acids (HAA5), Barium. This data comes from source-level compliance monitoring at wells and treatment plants.

Does WEST DUNDEE water meet EPA standards?

Based on available public monitoring data, no contaminants were measured above federal EPA standards in recent compliance monitoring. However, 2 contaminants exceed independent health guidelines, which are often stricter than legal limits. This assessment is based on source-level monitoring data (wells and treatment plants), not tap-level measurements.

Is WEST DUNDEE, IL water safe to drink?

Based on source-level compliance monitoring, all tested contaminants were within federal standards. However, compliance monitoring tests water at wells and treatment plants, not at individual taps. An on-site test is the only way to know what reaches your tap, as conditions can vary based on plumbing, blending, and distribution.

Does WEST DUNDEE water have lead?

No. WEST DUNDEE's most recent Lead and Copper Rule testing found a 90th-percentile lead level of 0.008 mg/L, which is below the EPA action level of 0.015 mg/L. That means at the systemwide level, lead is not exceeding the enforcement threshold. Lead levels can still vary significantly by individual building — older homes and schools with legacy plumbing can have much higher readings than the system average.

Cross-check against the official record

This report is our read of the public monitoring data. Every Illinoisutility also publishes an annual Consumer Confidence Report (CCR) — a plain-language summary written by the utility itself, usually mailed with a water bill or posted on the utility's website. If anything in this report surprises you, request WEST DUNDEE's latest CCR directly from the utility, or browse the underlying compliance data published by Illinois EPA.

Data Sources and Methodology

Illinois EPA Compliance Monitoring

State-level drinking water compliance testing. Covers all regulated contaminants for community water systems. Source-level monitoring at wells and treatment plants. Individual result links are provided for each contaminant in the tables above.

Water Quality Portal

Cooperative service by USGS, EPA, and NWQMC. Regional groundwater monitoring data from nearby wells — may not reflect this specific utility.

EPA ECHO Lead & Copper Rule

90th percentile measurements from EPA Enforcement and Compliance History Online. Based on tap-level sampling at high-risk sites.

EPA UCMR5

Unregulated Contaminant Monitoring Rule, Fifth cycle. Per-analyte PFAS results from utility-level sampling.

Definitions

Maximum Contaminant Level (MCL)
The highest level of a contaminant allowed in drinking water, set by the EPA. MCLs are legally enforceable standards.
Maximum Contaminant Level Goal (MCLG)
The level of a contaminant below which there is no known or expected health risk. MCLGs are non-enforceable public health goals.
Action Level
The concentration of a contaminant which, if exceeded, triggers treatment or other requirements. Used for lead and copper.
Health Advisory
Non-enforceable guidelines set by the EPA providing information on contaminants that can cause health effects at certain exposure levels.
Total Dissolved Solids (TDS)
A measure of all dissolved minerals, salts, and organic matter in water, expressed in mg/L (ppm). Not a health hazard but affects taste and indicates overall mineral content.
PFAS
Per- and polyfluoroalkyl substances. A group of manufactured chemicals that do not break down in the environment. The EPA set enforceable limits for several PFAS compounds in 2024.
Non-Detect (ND)
The contaminant was tested for but not found above the laboratory's reporting limit. This does not mean zero — it means below the detection threshold.
VOCs (Volatile Organic Compounds)
Chemicals that evaporate easily and can contaminate groundwater. Sources include gasoline, industrial solvents, and dry cleaning fluids. Some are regulated by the EPA; many are monitored but not yet regulated.

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Cite This Report

WaterAdvantage. "Water Quality Technical Report: WEST DUNDEE, IL (IL0890950)." WaterAdvantage.org, 2026-11-01. https://www.wateradvantage.org/report/IL0890950/detail

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