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Fact Sheet 2 July 2012 Update

Sauk Village Public Water Supply Contamination
Sauk Village, Illinois
Cook County

Detections of vinyl chloride have occurred in the source water wells providing water for the Sauk Village community water system (CWS) since 2009. Vinyl chloride is a man-made chemical that is found in groundwater from break-down products of solvent-type chemicals. When vinyl chloride is detected, it can indicate spills or releases that occurred 25 years or more in the past. The water supply wells and the finished water that is provided to residents is being sampled and analyzed by Illinois Environmental Protection Agency (Illinois EPA) staff on a weekly basis to make sure that water provided to the community is safe to drink.

At 50% the federal Safe Drinking Water standard (which is 1 part per billion for vinyl chloride), notification is required to all water users. On July 16, 2012, the Illinois EPA issued a letter to Sauk Village requiring notification to residents that vinyl chloride was detected in the finished water that enters the distribution system. This notification level – 1 part per billion for vinyl chloride – is the new “early warning” prevention standard enacted by the State of Illinois. This notification level does not indicate that the water is unsafe to drink.

Notification was performed purusant to the Right-to-Know law. In the water drawn from Well Number 3, the concentration of vinyl chloride in 2009 at 3.49 micrograms per liter (ug/L) violated the federal maximum contaminant level (MCL) of 2 ug/L allowed for a public water supply. Well Number 3 was taken out of service in 2009 and has not been part of the system since then.

The Right-to-Know law requires a CWS owner/operator to notify all end users when water is contaminated or there is a threat of contamination above groundwater quality standards. This law establishes methods of notification and strict time frames for meeting the required notifications. Public notices are posted on the Illinois EPA Notices to Public Water Supply Users about Groundwater Contamination webpage (includes Sauk Village notices).

At this lower level, steps must be taken by Sauk Village to reduce the concentration of the vinyl chloride to below the prevention level of 1 ppb. The Illinois EPA and the Illinois Office of the Attorney General are pursuing legal enforcement against Sauk Village to correct water quality problems related to the community water supply and provide bottled water to residents and businesses who want it.

Is the Sauk Village community water system (CWS) currently safe?

The CWS detection level is still less than the federal drinking water quality standard for vinyl chloride. The Illinois EPA and Illinois Department of Public Health (IDPH) advise no restrictions on use of the Sauk Village water supply at this point – either by residents or businesses. Those uses include drinking, bathing/showering, and cooking with the water. However, the contaminant level in the water supply is getting close to violating the federal drinking water standard. Consequently, the Illinois EPA is sampling both the well water and the finished water on a weekly basis to make sure the water is safe to consume and is requiring that Sauk Village make bottled water available to those who want it.

What health effects can result from consuming vinyl chloride in drinking water?

Exposure to low levels of vinyl chloride at or above the maximum contamination level (MCL) of 2 ppb over many years may lead to impaired immune system function; kidney or liver damage; and may increase the risk of liver cancer. The United States Environmental Protection Agency (U.S. EPA) has determined that drinking water with 2 parts per billion of vinyl chloride over an entire lifetime corresponds to an excess lifetime cancer risk of 1 in 10,000.

Can the vinyl chloride be removed from the water?

Yes. There are various forms of treatment to remove the contamination after the water is drawn at the well before it goes into the system that delivers water to the users. Part of the enforcement action by the Illinois Attorney General Office and the Illinois EPA is to demand that Sauk Village begin treatment of the water immediately.

Does the Illinois EPA know the source of the contamination groundwater?

The Illinois EPA does not currently know the source or sources of vinyl chloride contamination and is currently conducting investigations and gathering information about potential sources.

How can I reduce my risk of exposure?

There is no immediate health risk from using the water with vinyl chloride levels below 2 ppb. Exposure to vinyl chloride may increase the risk of cancer over many years – the higher the level and the longer the exposure, the greater the risk. However, if you are concerned that any exposure to vinyl chloride may pose a threat to the health of you or your family, you may choose to drink bottled water or water from an alternate source. You may also reduce your exposure to vinyl chloride vapors from contaminated water by running an exhaust fan or opening a window during showering and bathing. Risk posed by water uses is minimal.

Does Sauk Village have other water quality issues besides the vinyl chloride contamination?

Yes. Other aesthetic water quality issues may include iron or manganese content or other naturally-occurring substances that cause issues with taste or may form stains on clothing and fixtures. This in itself is not usually a problem for public health. However, these water quality parameters are monitored as well. Please refer to the IDPH brochure, Commonly Found Substances in Drinking Water.

How can I look up Sauk Village water quality data?

Below is a list of steps to take to view sampling data information for public water supplies. It is optional to view information on bacterial contamination (coliform sample results) or chemical (non-coliform sample results by analyte).

Additional Information and Resources

Contact

For more information, please contact the Illinois EPA Office of Community Relations. Additional documents not available on this webpage may be obtained through a Freedom of Information Act request or through IEPA Document Explorer.

A printable PDF version of this fact sheet is available.