Operable Unit 4, Groundwater/Surface Water and Ecological Risk
Operable Unit Description
Operable unit 4 concerns the impact of the lead, zinc, copper and cadmium contamination on the regional ground water and surface water (Aquashicola Creek) and includes a site wide ecological risk assessment.
OU 4 concerns an area-wide investigation of contamination in the surface water and ground water. EPA sent Special Notice letters to the Potentially Responsible Parties for the Site on December 22, 1995, offering them the opportunity to perform the RI/FS for OU 4. All of the parties declined and EPA decided to perform the RI/FS using money from Superfund rather than issuing Unilateral Administrative Orders for performance of the work. The field work for the ecological part of the remedial investigation took place during 1997 and 1998. The preliminary results of this ecological investigation will be presented to EPA in the draft ecological risk assessment to be submitted in June, 1999. The groundwater investigation is being performed in three phases. The first phase included the evaluation of all existing groundwater data including the results of recently sampled existing on-site monitoring wells, four residential wells and existing monitoring well data. The results of this evaluation will be used to determine if the second phase of the groundwater investigation (installation of additional shallow monitoring wells) will be necessary. The results of the first phase of the investigation will be made part of a presentation to be given to the Joint Groundwater Committee.