Operable Unit 2, USS Lead Superfund Site
Update - February 2020
Operable Unit 2 is the designated name for the former USS Lead facility and the groundwater (underground water) beneath the entire USS Lead site, including the residential neighborhood. EPA is overseeing the environmental investigation at OU2 conducted by the parties potentially responsible for the contamination under a legal framework called a Remedial Investigation/Feasibility Study Administrative Settlement Agreement and Order on Consent.
As part of the Remedial Investigation, contractors working on behalf of the potentially responsible parties installed groundwater monitoring wells in the residential neighborhoods in November and December 2018. Groundwater monitoring wells in the residential neighborhood and at the former industrial facility were sampled every three months starting in December 2018. Soil sampling was conducted in the non-excavated wetlands on the southern half of the former USS Lead facility, and tissue samples from plants and invertebrate (no backbone) animals were collected as part of an ecological assessment in May and June 2019. Data from 2018 and 2019 sampling efforts were compiled and presented in a draft Remedial Investigation Report submitted to EPA in January 2020.
In response to concerns that groundwater seepage is bringing contaminants that pose a health risk into the basements of homes, EPA collected dust and sump water samples in a subset of homes in Zone 3. At this time, 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 conducted at the Site determined that groundwater is not used for drinking purposes and EPA is not aware of any household use of groundwater in the neighborhood. All residents are connected to East Chicago municipal water, which uses Lake Michigan as its water source.
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 OU1 the priority before initiating an investigation at OU2. All residents are connected to East Chicago municipal water, which uses Lake Michigan as its water source. Access to the land area of OU2 is restricted. Therefore, risk to the public from OU2 contamination is much lower than OU1.