Collecting fish samples to provide analytical data for tracking future sediment remediation efforts

OUR CHALLENGE

Integral conducted a predesign investigation on an urban river to collect fish tissue samples for chemical analyses. We obtained samples from two impoundments impacted by a Superfund site and from two unaffected upstream reference impoundments. Our goals were to compare measured tissue concentrations to chemical-specific target tissue levels, assess differences in fish tissue concentrations among and between those from site-affected and upstream impoundments, and establish a pre-remedial fish tissue concentration baseline for each impoundment. This investigation provided baseline tissue data for three target fish species to support the river’s post-remediation monitoring efforts.  

OUR APPROACH

Before starting the field sampling activities, Integral designed the study to ensure that the analytical data would address the research questions and support defensible conclusions.  We used electroshocking, gill nets, trot lines, and eel pots to capture the target fish species. Following collection, we processed the fish and sent tissue samples to a laboratory for chemical analysis. We then conducted comparative and statistical evaluations to address all project-related questions. The outcome was a comprehensive data summary report detailing the field activities, data analyses, and results for review by the oversight agency.  

OUR IMPACT

Integral provided insights into the pre-remediation contaminant levels in fish tissues from the two impacted impoundments. The detection of certain chemicals in fish from the upstream reference impoundments indicated the potential challenge of attaining all target tissue levels in the affected impoundments post–remediation. These findings offer guidance for interpreting long-term monitoring of fish tissue concentrations following the implementation of a sediment excavation remedy.