Region 5 Superfund (SF)

U.S. EPA REGION 5
WINNEBAGO COUNTY
ROCKFORD

Congressional District # 16

SOUTHEAST ROCKFORD GROUND WATER CONTAMINATION

EPA ID# ILD981000417
Last Updated: October, 2006

Site Description

The S.E. Rockford Groundwater site, was originally identified as an area of about 0.7 square miles. Several subsequent investigations have defined a very large area of groundwater contamination; the site now encompasses about three square miles. Land use within the site is mainly residential with smaller industrial/commercial developments. The population within one mile of the site is approximately 52,000 people.

The primary site contaminants are chlorinated solvents in soil and groundwater. Trichloroethene (428ppb), tetrachloroethene (545ppb), 1,1,1-trichloroethane (991ppb), cis-1,2-dichloroethene (1,233ppb) and vinyl chl oride (114ppb) have been found in residential wells. High levels of similar compounds have also been identified at four source areas of this groundwater contamination. Localized high groundwater concentrations of benzene, toluene, ethylbenzene, and xylene also exist.

Site Responsibility

This site is being addressed through Potentially Responsible Party, federal and state actions.

Threats and Contaminants

The primary site contaminants are chlorinated solvents in soil and groundwater. Trichloroethene (428ppb), tetrachloroethene (545ppb), 1,1,1-trichloroethane (991ppb), cis-1,2-dichloroethene (1,233ppb) and vinyl chloride (114ppb) have been found in residential groundwater wells. High levels of similar compounds have also been identified at four source areas.

Cleanup Progress

U.S. EPA performed the first action at the site in 1991 as a time-critical removal action. It included providing service connections for 283 residents to the municipal water supply and the installation of granular activated carbon treatment on Rockford Municipal Well #35.  In 1992 an action to connect an additional 264 homes to municipal water service performed by Illinois Environmental Protection Agency (Illinois EPA) and U.S. EPA . 

In September 1995, the EPA established long-term cleanup goals for the contaminated aquifer and selected natural attenuation as the cleanup approach. This decision was made with the assumption that major sources of contamination at the site would be addressed under a subsequent action. This decision also called for connection to the municipal water system of homes and businesses whose water wells either recently exceeded health standards or were predicted to exceed them within the next 70 years.

The city of Rockford began implementation of the final groundwater remedy in early 1998 under an enforcement action with Illinois EPA and U.S. EPA. Installation of over 9,200 feet of ductile iron water mains and hookup of an additional 262 homes/businesses to water service connections was accomplished by June 1999. Nine additional groundwater monitoring wells were installed to supplement the existing monitoring network. A groundwater monitoring program has been established. Since 1999, groundwater sampling results have been compiled by the city of Rockford and have been reported to U.S. EPA and Illinois EPA. Such monitoring is to continue until cleanup goals are attained.

A separate enforcement action, designed to recover U.S. EPA's and Illinois EPA's past costs, has also been developed. This recovered money is targeted to address the largest of four contaminated soil areas. All four areas continue to pose a potential threat of further contaminant release. Private parties have contributed to this fund. 

Illinois EPA has taken the lead on the remedial investigation to evaluate the nature and extent of site contamination, and a study to evaluate site cleanup options, for the four major sources of groundwater contamination. In June 2002, a decision was made on how to address these source areas. Source control techniques include soil vapor extraction, low temperature thermal desorption, and soil excavation. Pending unique source characteristics, some surface/near surface soil work may be supplemented with source-specific groundwater management zones and the use of techniques such as air sparging (using air under pressure below the water table to help remove contaminants from the groundwater) or limited pump and treat steps. This potential work is limited to a limited source area and is not applied to the overall site plume. The state has now begun the remedial design process at three of the four source areas. U.S. EPA finalized negotiations in early 2003, and as a result remedial design work at the fourth source area (Area 9/10) will be done privately.

Remedial action has begun at one of the source areas.  An initial step in 2005 was excavation of about 200 cubic yards of contaminated soil.  In 2006, groundwater management zone work began.

At another source area, the next step in remedial design is the conduct of a radius of influence test for a soil vapor extraction well. A consent decree for settlement of response  costs with a property owner was lodged with the federal court. 

U.S. EPA and Illinois EPA are reviewing design plans recently received  for the third source area.

 

 

 

Contacts

Remedial Project Manager, U.S. EPA
shari kolak (kolak.shari@epa.gov)
(312) 886-6151

Community Involvement Coordinator, U.S. EPA
mike joyce
(312) 353-5546

Aliases

SOUTHEAST ROCKFORD GD WTR CONTAMINATION
SOUTHEAST ROCKFORD DRY WELL
SE ROCKFORD GROUNDWATER CONT

 

Site Profile Information

This profile provides you with information on EPA's cleanup progress at this Superfund site.