As part of a feasibility study for a former landfill in New Jersey, we were asked to evaluate the ecological protectiveness of a range of remedial options. Our challenge was to estimate the “residual” ecological risks for multiple remedial alternatives. This work was a follow-up to the baseline ecological risk assessment (BERA) that we had prepared previously for this site.
We focused the residual ecological risk assessment on those receptors and chemicals that showed potential risk in the BERA, and then adjusted the exposure inputs (soils and modeled media concentrations) to reflect the different capping alternatives. The soil inputs for the different alternatives included replacement of cap area soil sample results with equivalent background levels.
Our residual ecological risk assessment was submitted as part of the feasibility study. It showed that the preferred capping alternative would be protective of ecological receptors. The results will ultimately be used to support the development of the Record of Decision for this site.