The U.S. Environmental Protection Agency recently issued a Record of Decision detailing cleanup plans for 8.3 miles of polluted sediments in the Lower Passaic River. In support of EPA’s Focused Feasibility Study, Battelle conducted human health and ecological risk assessments that were used to inform the decision-making process.
The Passaic River runs through Northern New Jersey, an area that has been heavily industrialized for more than a century. Throughout its history, a number of chemical plants and pesticide manufacturers were established near the river, including a plant producing the herbicide Agent Orange. The Lower Passaic is considered to be one of the most polluted waterways in the U.S. It was declared a Superfund site in 1984 when high levels of dioxin, PCBs, mercury and other toxic chemicals and heavy metals were found in river sediments.
The new decision outlines the remediation plan for the most polluted segment of the river, an 8.3-mile stretch that extends from the river’s confluence with Newark Bay to the City of Newark/Belleville Township border. The cleanup plan includes dredging approximately 3.5 million cubic yards of contaminated sediment bank to bank along the entire stretch. After dredging, an engineered cap will be placed over the entire lower eight miles of the river. The cap will prevent contamination in the sediment from entering the food chain, thereby decreasing ecological impacts and health risks to people who eat fish and crab from the lower Passaic River. The dredging will prevent the cap from exacerbating flooding and will allow for current commercial navigation to continue in the 1.7 miles of the river closest to Newark Bay. Dredged sediment will be dewatered locally and transported off-site for disposal. The estimated cost of the remedy is $1.38 billion.
Battelle contributed to the studies that informed development of the final plan under a contract with The Louis Berger Group, Inc., the technical lead for the EPA study. Battelle was primarily responsible for conducting risk analysis of potential impacts to human health and the environment. Using samples collected by EPA and responsible parties, along with mathematical models developed by HDR Hydroqual, Battelle analysts were able to quantify and predict the human and ecological risks associated with each of the proposed remedy options. EPA used these calculations to determine the best option based on risk reduction, estimated costs and overall cleanup objectives.
Battelle has a long history of risk assessment work for similar environmental projects for the EPA and other government agencies. The Battelle environmental team brings together deep expertise in environmental science, data analysis, risk assessment and remedy selection and optimization. Battelle is also currently working on the Centredale Superfund site in Rhode Island, another high-profile EPA site, with services spanning risk assessment and sample collection and analysis.
With preliminary studies complete and final decisions made, the EPA is now ready to move forward with the selected remedy. The agency is currently in discussions with responsible parties to arrange for payment for performance of the required work. The final, legally binding project design will take three to four years to complete. Dredging, dewatering and disposal of dredged materials will follow and is expected to take six years to complete. Battelle will continue to provide risk assessment support during the course of the remediation work.