Operable Unit 2 (facility and groundwater)
May 2025
EPA is overseeing the environmental investigation at Operable Unit 2 conducted by the parties potentially responsible for the contamination. Operable Unit 2 (OU2) is the name for the former USS Lead facility and the groundwater beneath the USS Lead site and the residential neighborhood. Read more about the agreement or Administrative Order on Consent. (pdf) (2.61 MB)
Beginning in late 2018, contractors working on behalf of the potentially responsible parties installed groundwater monitoring wells in the residential neighborhood, and have sampled groundwater, soil, sediment, and plant and invertebrate animal tissue. The potentially responsible parties have developed plans to collect additional data in 2025, after which all site data will be evaluated in a remedial investigation report, human health risk assessment, and ecological risk assessment.
EPA collected dust and sump water samples in a subset of homes in Zone 3 in response to concerns about groundwater seepage into basements. EPA is not aware of any on-site residences where a site-related risk of exposure to contamination from groundwater seepage exists in the basement.
Groundwater use and basement evaluations determined that groundwater is not used for drinking purposes. All residents are connected to East Chicago municipal water, which uses Lake Michigan as its water source. EPA is not aware of any household use of groundwater in the neighborhood.
EPA decided to first address areas of the site that present the most risk to the public, making the contamination in the residential areas in Operable Unit 1 (OU1) the priority before initiating an investigation at Operable Unit 2. Access to the land area of OU2 is restricted.