Fact Sheet 2 March 1991

Southeast Rockford Groundwater Contamination
Rockford, Illinois
Winnebago County

In March 1989, an area in southeast Rockford bounded by Harrison Avenue, 21st Street, Sawyer Road, and 8th Street was finalized on the National Priorities List (NPL) because of industrial solvents from an unknown source or sources found in private wells and Rockford Municipal Well #35. The National Priorities List is a list of hazardous waste sites eligible for investigation and cleanup money under federal Superfund law.

In late 1989, the United States Environmental Protection Agency (U.S. EPA) Emergency Response Branch sampled private wells in the site boundaries and beyond. The U.S. EPA provided bottled water, then water filters to residences with well contamination high enough to pose a possible health risk from short term exposure. The U.S. EPA Emergency Response Branch has completed Rockford public water main hookups for approximately 280 of these residences.

In June 1990, the Illinois Environmental Protection Agency (Illinois EPA) began an Operable Unit (one part of the overall investigation and cleanup) which involved private well sampling in an area bounded by Harrison Avenue, Sandy Hollow Road, 24th Street and the Rock River. These boundaries were based on U.S. EPA sample results. The purpose of the samples was to identify wells with lower contaminant levels which may pose a possible health risk from long term (a lifetime) exposure. In late 1990, the Illinois EPA conducted a feasibility study describing drinking water alternatives for identified wells which meet the proposed criteria outlined in this Fact Sheet.

Recently, the study area was expanded eastward to approximately one and a fourth mile east of Alpine Road. Study area boundaries do not indicate known areas of contamination but simply represent the present geographical area of investigation. To find the source(s) of contamination, areas free of contamination must be identified. By comparing groundwater flow between contaminated and uncontaminated areas within the study area, one can focus on possible contamination sources. This investigation of potential sources will begin this spring.

This Fact Sheet summarizes the June sample results, describes drinking water alternatives examined in the feasibility study, and outlines the alternative preferred by the Illinois EPA and U.S. EPA for affected wells.

117 wells were tested by the Illinois EPA in June 1990. The Illinois EPA chose sample locations on a grid system to supplement samples already taken by the Illinois Department of Public Health (IDPH) and U.S. EPA. Not every house needed to be sampled to evaluate the water quality of an area.

The water was tested for nine volatile organic compounds (VOCs), many of which are commonly used industrial solvents, and for four metals. All but one of these chemicals had been found in previous samples of private wells in the area.

• Trichloroethene
• 1,1,1-trichloroethane
• Cis-1,2-dichloroethene
• Trans-1,2-dichloroethene
• 1,2-dichloroethane
• 1,1dichloroethane
• 1,1-dichloroethene
• Tetrachloroethene
• Vinyl chloride

• Arsenic
• Cadmium
• Chromium
• Lead

The well samples were not tested for bacteria or nitrates. If you are concerned about bacteria or nitrates in your private well, you should contact the Winnebago County Health Department.

• 31 wells had no detected contamination.
• 25 wells had contaminants at levels which violated the U.S. EPA public water supply standards.
• 60 wells had small amounts of contaminants at levels which did not violate U.S. EPA public water supply standards.
• One well had one contaminant for which there is no standard.

Lead was the only metal detected at levels violating public water supply standards.

The Illinois EPA is concerned about chemical concentrations that violate U.S. EPA standards for public water supplies, because these concentrations may pose a health risk for people who consume the water for a lifetime. There are no standards for private wells. Many of the industrial solvents detected may affect the liver, kidneys, and central nervous system. Several are classified by the U.S. EPA as probable cancer causing agents in humans. Vinyl chloride, which was detected in three wells, is classified by the U.S. EPA as a known cancer causing agent in humans.

The Illinois EPA and the U.S. EPA considered four alternatives as possible remedies for wells in the Southeast Rockford study area which violate public water supply standards and meet other criteria discussed below. The four alternatives are:

Alternative 1 - Hookups to Rockford Public Water Supply

In this alternative, the U.S. EPA and the Illinois EPA would pay for the extension of the water main down the street (if necessary), for the service connection from the street to the house, for the water meter, and for plugging the private well. The resident would be responsible for the monthly water bill to the City of Rockford. The Illinois EPA is negotiating with the City of Rockford to waive the hookup fee.

This alternative includes the treatment of Municipal Well #35 with a granular activated carbon treatment facility. This facility would remove VOCs detected in the well to allow the City to use this well during peak demand.

Cost of Alternative 1: $5,820,000

Alternative 2 - New residential water wells

This alternative involves the construction of new deeper water wells at each of the affected residences. This alternative is based on the assumption that the deeper water supply is not contaminated. The U.S. EPA and the Illinois EPA would pay for the construction of the new well and plugging the old contaminated well at each residence.

Cost of Alternative 2: $6,970,000

Alternative 3 - Point of entry water treatment devices

This alternative involves the installation of individual treatment units at affected residences. The treatment system would be designed to removed VOCs from the water before it was distributed in the house.

Cost of Alternative 3: $18,250,000

Alternative 4 - No action

Federal law requires that the "no action" alternative be considered. "No action" means that no action would be taken to provide alternative water.

Cost of Alternative 4: $0

Proposed Plan

The Illinois EPA and the U.S. EPA prefer Afternative 1 (hookups to the Rockford public water supply) as the method for providing safe water to residents with well water that violates public water supply standards and meets the criteria described below. This alternative is most satisfactory, because it is a cost effective method of providing a permanent source of safe water for residents whose wells meet the criteria.

The Illinois EPA and the U.S. EPA rejected Alternative 2 (new residential wells) for several reasons including the fact that groundwater quality at greater depths is unknown and cannot be guaranteed to provide safe water to residents in the future.

Alternative 3 (point of entry water treatment devices) was rejected because of cost and because of the ongoing expense and commitment required to maintain the water filters. Alternative 4 (no action) was rejected, because it did not protect human health.

What are the criteria for Alternatives 1, 2, or 3?

The Illinois EPA proposes the following criteria to determine which wells are eligible for the first three alternatives.

1. Wells must be located within the boundaries of the contamination, as indicated by points sampled, where contaminants violate the public water supply standards or within the buffer zone. See centerfold map for proposed area of hookups.
2. Wells must be a source of drinking water for humans.
3. Water from the wells cannot be "sold". For example, restaurant or tavem wells would not be eligible for IEPA and U.S. EPA funded hookup to the Rockford public water supply.

Table 1 lists proposed target addresses of known wells which would be eligible for a drinking water remedy if Alternative 1, 2, or 3 are chosen. 

Yes. Within the next two years, the Illinois EPA will sample select wells in the study area to determine if additional wells have become contaminated at concentrations which violate the public water supply standards. If so, these wells will be eligible for the chosen alternative.

Repositories and Administrative Record

More information on the Southeast Rockford Groundwater Contamination may be found in project repositories located at the Rockford Public Library and the Ken-Rock Community Center.

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.