Site 12 - Harbor Dredge Spoil Area
During harbor dredge activities in 1952 and the 1970s, dredge spoils were reportedly disposed in this area. The sediment dredged from the harbor may have high organic content and potentially contain heavy metals, oils, pesticides, and PCBs. The primary sources for the environmental contaminants in the sediments are from non-Navy upstream industrial sources (historical discharges and contamination), and non-Navy and Navy storm water discharges within the Pettibone Creek Watershed. Overland runoff and storm water discharges from Naval Station Great Lakes to Pettibone Creek may have historically contributed pollutants to the watershed; however, the Navy currently manages discharges through the appropriate storm water management regulations, and recent analytical results indicate that no significant Navy point sources are impacting the sediment quality of Pettibone Creek.
A RI was conducted to determine the nature of fill material(s) that were placed in the Harbor Dredge Spoil Area, and to identify potential risks associated with Site 12. The chemical data for Site 12 were used to delineate areas of impacted soil/fill, evaluate the potential for metals to migrate to groundwater, and conduct a HHRA and an Ecological Risk Assessment for the site.
The RI was completed in three phases. The RI fieldwork conducted in December 2010 and December 2012 consisted of the drilling of soil borings, and collecting and analyzing soil samples. The RI fieldwork conducted in August 2013 consisted of installing monitoring wells, and collecting and analyzing groundwater samples.
The Site 12 ROD was signed in 2016, and documents a remedy including LUCs. LUCs were implemented in 2017 to restrict future use of the site, prohibit installation of groundwater wells other than for environmental sampling, and require annual inspections of the site to make sure LUCs are continuing to be implemented.
Previous investigations, plans and documentation at this site are: IAS; RI/RA; FS; PP; and a ROD.
LUCs have been implemented at this site.