The Lenz Oil Service site near Lemont, Illinois, poses no apparent public health hazard because there is no human exposure to contaminants at levels of health concern at this time. Before the availability of a community water supply in 1988, some residents using private wells may have been exposed to low-level concentrations of groundwater contaminants. Presently, there are no known exposures to the residual surface soil contamination found at the site. Although much of the hazardous waste was removed or incinerated, groundwater continues to be contaminated by remaining subsoil contamination and by a nonaqueous layer of contaminants floating on the groundwater. In the future, the contaminated groundwater could pose a health threat due to its potential for continued down gradient migration to other private wells still used for drinking water.
Some gaps are in the fences, and people can enter the site.
Disallow applications for permits to drill new wells into the contaminated aquifer until groundwater remediation is completed. Maintain a good vegetative ground cover on site to help reduce contaminant migration and possible exposure. Site Characterization Recommendations Continue the groundwater monitoring program to augment the data which currently exist. This additional data could better characterize the movement of groundwater contamination off site and provide current levels of contamination to address potential adverse health effects to those individuals who may be exposed. Provide additional contaminant concentration information collected during future groundwater and soil cleanup to IDPH for consideration.